Category :
Article
article id 5630,
category
Article
John H. M. Thornley.
(1997).
Modelling allocation with transport/conversion processes.
Silva Fennica
vol.
31
no.
3
article id 5630.
https://doi.org/10.14214/sf.a8532
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A shoot-root carbon:nitrogen allocation model, based on the two processes of transport and chemical conversion, is described and explored. The view is proposed that all allocation models, whether built for the purposes of theoretical investigation or practical application, should start with this irreducible framework. In the present implementation, the processes operate according to: for substrate sources, dependence on shoot and root sizes, with possible product inhibition; for transport, movement down a substrate concentration gradient; for substrate sinks or utilization, linear bisubstrate kinetics. The dynamic and equilibrium properties of the model are explored. Failure of this approach to allocation will indicate to the modeller that additional mechanisms to control the processes are needed, and the mode of failure will indicate the type of mechanisms required. Additional mechanisms are discussed which may involve hormones or teleonomic (goal-seeking) controls, and may be added to the irreducible framework. However, these additions should not replace the irreducible framework of transport and chemical conversion, because they do not in reality. Modifications to the basic model to reflect some possibilities such as ontogenesis with the transition from exponential growth towards a steady state or with the scaling of within-plant transport resistances, the influence of hormones, and active transport, are described.
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Thornley,
E-mail:
jt@mm.unknown
article id 5622,
category
Article
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Process-based tree growth models are recognized to be flexible tools which are valuable for investigating tree growth in relation to changing environment or silvicultural treatments. In the context of forestry, we address two key modelling problems: allocation of growth which determines total wood production, and distribution of wood along the stem which determines stem form and wood quality. Growth allocation and distribution are the outcome of carbon translocation, which may be described by the Munch theory. We propose a simpler gradient process to describe the carbon distribution in the phloem of conifers. This model is a reformulation of a carbon diffusion-like process proposed by Thornley in 1972. By taking into account the continuity of the cambium along the stem, we obtain a one-dimensional reaction-diffusion model which describes both growth allocation between foliage, stem and roots, and growth distribution along the stem. Distribution of wood along the stem is then regarded as an allocation process at a smaller scale. A preliminary sensitivity analysis is presented. The model predicts a strong relationship between morphology and foliage-root allocation. It also suggests how empirical data, such as stem analysis, could be used to calibrate and validate allocation rules in process-based growth models.
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Deleuze,
E-mail:
cd@mm.unknown
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Houllier,
E-mail:
fh@mm.unknown
article id 5617,
category
Article
Teijo Palander.
(1997).
A local DLP-GIS-LP system for geographically decentralized wood procurement planning and decision making.
Silva Fennica
vol.
31
no.
2
article id 5617.
https://doi.org/10.14214/sf.a8518
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Linear programming (LP) is an important method for allocation of wood inventory stock. It is, for instance, used alone in tactical planning systems, which currently are in wide use at the higher hierarchical level in the functionally decentralized planning of the Finnish forest industry. Unfortunately, LP as a solution method has not been capable of handling spatial data that seem to characterize planning systems in geographical decentralization. In the present study, GIS was used to assimilate data from different wood procurement functions, to calculate transportation distances and cost figures, and to write the data in ASCII files, which were then used as input for the LP model. Using the experiments and methods of GIS on a planning system developed according to participatory planning, the results of this study suggest that the participatory method was faster than the conventional LP method, when solved using actual data. The participatory method was also capable of providing the same global optimum for a wood allocation problem. The implications of these results for improving operational and tactical planning of wood procurement in Finland are discussed.
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Palander,
E-mail:
tp@mm.unknown
article id 5597,
category
Article
John C. Brissette.
(1996).
Effects of intensity and frequency of harvesting on abundance, stocking and composition of natural regeneration in the Acadian forest of eastern North America.
Silva Fennica
vol.
30
no.
2–3
article id 5597.
https://doi.org/10.14214/sf.a9242
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In a silviculture experiment in east-central Maine, USA, natural regeneration was sampled to measure the effects of: (1) a range of partial harvest intensities, and (2) repeated partial harvest at one intensity. Under the first objective, five treatments were compared with residual basal areas ranging from 15 to 24 m2 ha-1 for trees ≥1.3 cm diameter at breast height. For the second objective, regeneration was evaluated after four harvests at 5-year intervals. Prior to harvests, the overstory of all the treated stands was dominated by Tsuga canadensis (L.) Carr., Picea spp. A Dietr., and Abies balsamea (L.) Mill. Eleven species or species groups were identified among the regeneration: A. balsamea, T. canadensis, Picea spp., Thuja occidentalis L., Pinus spp. L., Betula papyrifera Marsh., Acer rubrum L., Betula populifolia Marsh., Populus spp. L., Fagus grandifolia Ehrh. and Prunus serotina Ehrh. Regeneration abundance was measured as counts of seedlings or sprouts taller than 15 cm but with diameters less than 1.3 cm at breast height (1.37 m). Regardless of harvest treatment, total regeneration was profuse, ranging from over 25,000 to nearly 80,000 trees ha-1. Regeneration was dominated by conifers with a total angiosperm component of 10 to 52 percent approximately 5 years after harvest and 11 to 33 percent after 10 years. Consequently, in forests of similar species composition, tree regeneration following partial harvests should be sufficiently abundant with an array of species to meet a variety of future management objectives.
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Brissette,
E-mail:
jb@mm.unknown
article id 5562,
category
Article
Janne Uuttera,
Matti Maltamo.
(1995).
Impact of regeneration method on stand structure prior to first thinning. Comparative study North Karelia, Finland vs. Republic of Karelia, Russian Federation.
Silva Fennica
vol.
29
no.
4
article id 5562.
https://doi.org/10.14214/sf.a9213
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Comparisons were made between artificially and naturally regenerated stands in the south-eastern part of North Karelia, Finland, and naturally regenerated stands in the western parts of the Republic of Karelia, Russian Federation. The effect of soil fertility and silvicultural operations on the stand structure was also investigated.
The results of the study show clearly that when forests are artificially regenerated the stand structure includes less variation when compared with the stands naturally regenerated. Differences between the regeneration methods are clearer the more fertile the forest site is. Within the regeneration method there is also a clear trend in stand structure, with the variation decreasing the poorer the site. The effect of silvicultural operations, i.e. the cleaning of the sapling stand, has disappeared by the time of first thinning, although it appears to have a permanent effect on the dynamics of the tree species within a stand.
The variation of the stand structure can be regarded as an essential factor for the potential biodiversity of the stand also at its young vegetation succession stage. This capacity for maintaining the forest biodiversity, developed at the young vegetation succession stage, becomes increasingly important in subsequent vegetation succession stages. Natural regeneration provides improved possibilities for the operations preserving forest biodiversity, as it generates more dense stands with a wider variation in stand structure, compared to artificial regeneration.
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Uuttera,
E-mail:
ju@mm.unknown
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Maltamo,
E-mail:
mm@mm.unknown
article id 5552,
category
Article
Liisa Saarenmaa,
Timo Leppälä.
(1995).
Fill-in seedlings in constituting the stocking of Scots pine stands in northern Finland.
Silva Fennica
vol.
29
no.
2
article id 5552.
https://doi.org/10.14214/sf.a9203
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Fill planting is a common procedure following reforestation in Finland. In 1990, 13% of the total of seedlings planted was used for fill planting. The objective of this study is (i) to survey the survival of fill-in seedlings and (ii) to estimate the spatial pattern of stands to evaluate the importance of fill-in seedlings in constituting the stocking of Scots pine (Pinus sylvestris L.) stands in Central and Northern Finland.
A survey of 63 artificially regenerated Scots pine stands was conducted in 1990. Stand densities varied from 950 to 3,925 seedlings/ha. The mean densities of originally planted, fill planted and naturally regenerated seedlings were 863, 639 and 791/ha, respectively. The survival of originally planted seedlings was 36% and that of fill-in seedlings 48%. Death rate of fill-in seedlings of Scots pine increased with longer times between original and fill planting. The survival rate of Norway spruce (Picea abies) seedlings was correlated with temperature sum. Height of the fill-in seedlings was less than that of the originally planted ones. Most stands had an even spatial distribution with the exception of sparsely populated stands, which were somewhat clustered. This indicates that dying of seedlings is not randomly spread. Because of poor survival, fill planting seems to be a risky business in most cases.
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Saarenmaa,
E-mail:
ls@mm.unknown
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Leppälä,
E-mail:
tl@mm.unknown
article id 5529,
category
Article
Jukka Lippu.
(1994).
Patterns of dry matter partitioning and 14C-photosynthate allocation in 1.5-year-old Scots pine seedlings.
Silva Fennica
vol.
28
no.
3
article id 5529.
https://doi.org/10.14214/sf.a9169
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Change in dry matter partitioning, 14C-incorporation, and sink 14C-activity of 1.5-year-old Scots pine (Pinus sylvestris L.) seedlings grown in growth chamber conditions were studied during a 91-day experiment. On five sampling dates, seedlings were labelled with 14CO2 and whole-plant allocation patterns were determined. Intensively growing shoots modified the dry matter partitioning: during shoot growth the proportion of roots decreased but after that it increased. Based on their large proportion of dry matter, the needles (excluding current needles) were the strongest sink of carbon containing 40% of the incorporated 14C. Despite their small initial sink size, the elongating shoots (current main shoot + current branch) and their needles were the second strongest sink (30–40% of the total 14C) which reflects their high physiological activity. The proportion of 14C in the current year’s main shoot increased during shoot growth but decreased as the growth began to decline after 70 days. 10–20% of the total assimilated 14C was translocated to the roots. Laterals above 2nd order were the strongest sink in the root system, containing twice as much 14C as the other roots together. Alternation between shoot and root growth can be seen clearly: carbon allocation to roots was relatively high before and after the period of intensive shoot growth. Changes in root sink strength resulted primarily from changes in root sink activity rather than sink size.
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Lippu,
E-mail:
jl@mm.unknown
article id 5445,
category
Article
Taneli Kolström.
(1991).
Kuusen kylvö- ja istutuskoe viljavilla kivennäismailla Pohjois-Karjalassa.
Silva Fennica
vol.
25
no.
2
article id 5445.
https://doi.org/10.14214/sf.a15599
English title:
Results from the sowing and planting experiment of Norway spruce (Picea abies) on fertile sites in North Karelia, Finland.
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Different methods of sowing and planting of Norway spruce (Picea abies (L.) H. Karst.) were compared on fertile sites in North Karelia (62°20’N, 29°35’E, 85–120 m a.s.l.). The planting material were 4-year-old bare-rooted transplants, 2-year-old bare-rooted seedlings, and 2-year-old containerized seedlings raised in plastic greenhouse. The sowing methods were band sowing and shelter sowing. Ground vegetation was controlled during the first growing season mechanically or chemically, or the control was omitted totally.
Planting of spruce gave better results than sowing. After eight growing seasons there were sowed seedlings left in 30% of the sowing pots. The average height of them was 35 cm. Seedling survival was best with large bare-rooted transplants (91%). Survival of containerized seedlings was 79% and of small bare-rooted transplants 71%. The average height of large bare-rooted transplants was 131 cm, of containerized seedlings 86 cm and small bare-rooted seedlings 68 cm.
Sowing is not an advisable method for regeneration of spruce due to the small survival rate and slow initial development when ground vegetation is controlled only once. Also 2-year-old seedlings gave a satisfactory result in regeneration. Seedlings raised in greenhouse were more sensitive to frost damage than seedlings grown on open ground.
The PDF includes an abstract in English.
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Kolström,
E-mail:
tk@mm.unknown
article id 5415,
category
Article
Kim von Weissenberg.
(1990).
Host-parasite relationships in forest ecosystems: A review.
Silva Fennica
vol.
24
no.
1
article id 5415.
https://doi.org/10.14214/sf.a15567
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Based on a survey of world literature it is concluded that 1) the better -researched epidemic forest pathosystems are caused by anthropogenic factors, 2) the systems most likely have a polygenic background, and 3) resistance breeding should maintain polygenic resistance with restrictive incorporation of oligogenic resistance. Corresponding objectives are valid in breeding programs of presently balanced pathosystems, which may turn epidemic if man causes changes in the gene pool and alters critical environmental conditions.
The PDF includes an abstract in English.
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Weissenberg,
E-mail:
kw@mm.unknown
article id 5404,
category
Article
Pentti Alho.
(1990).
Suomen metsittyminen jääkauden jälkeen.
Silva Fennica
vol.
24
no.
1
article id 5404.
https://doi.org/10.14214/sf.a15556
English title:
The history of forests in Finland after the last ice age.
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Based on literature this paper describes the natural afforestation of Finland that took place after the last ice age and the changes which have taken place during the last 10,000 years. The origin and development of the vegetation and trees are related to the changes in the edaphic and climatic factors. The first tree species to arrive in Finland were the primary colonizing species, birch and Scots pine. The appearance of Norway spruce dates back to about 5000 B.P. There have been great changes in the species composition of Finnish forests during the last several thousands of years but some 2,000–3,000 years ago the various species reached their present balance. The epoch of naural forests, which had lasted some 9,500 years, came to a conclusion, however, when man started to have a marked effect on the forest’s development 300–400 years ago.
The PDF includes an abstract in English.
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Alho,
E-mail:
pa@mm.unknown
article id 5368,
category
Article
Kari Heliövaara,
Rauno Väisänen.
(1989).
Invertebrates of young Scots pine stands near the industrial town of Harjavalta, Finland.
Silva Fennica
vol.
23
no.
1
article id 5368.
https://doi.org/10.14214/sf.a15527
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Invertebrates of young Scots pine (Pinus sylvestris L.) stands were preliminarily studied along a gradient of industrial air pollutants in Harjavalta, south-western Finland. Bark samples and net samples on pine branches and needles were taken in May–June, 1987. The number of aphids on needles was highest near the industrial plants. The number of mites in bark was positively correlated with the increasing distance from the pollutant source. Detrended correspondence analysis ordination calculated according to the bark invertebrates showed that the sampling sites of the zones far from the emission source formed a distinct group while those of the zones near the source were relatively widely dispersed indicating disturbances in faunal structure.
The PDF includes an abstract in Finnish.
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Heliövaara,
E-mail:
kh@mm.unknown
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Väisänen,
E-mail:
rv@mm.unknown
article id 5334,
category
Article
Aimo Reitala.
(1987).
Metsä suomalaisessa kuvataiteessa.
Silva Fennica
vol.
21
no.
4
article id 5334.
https://doi.org/10.14214/sf.a15491
English title:
Forests in Finnish art.
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The Finnish forest was elevated into an appreciated artistic motif by Werner Holmberg with his picture ”The Finnish conifer forest” in 1858. The second significant period was during national romanticism in the 1980’s, when the decorative beauty of the winter forests was discovered. At the turn of the century, the forest obtained a central national symbolic significance, and many leading artists regarded increased cuttings as a rape of the forests. Since that period, individual artists have succeeded in bringing new features in the art history of our forests.
The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.
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Reitala,
E-mail:
ar@mm.unknown
article id 5329,
category
Article
Bo Lönnqvist.
(1987).
Kultivoitunut metsä - herraskartanon puisto.
Silva Fennica
vol.
21
no.
4
article id 5329.
https://doi.org/10.14214/sf.a15486
English title:
Cultivated forests – the case of manor parks.
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The earliest manor parks, which are a special form of cultivated forests, were created at the end of the 18th century. The surrounding of the main buildings was divided into two parts, an aesthetic park and yard serving household and economic purposes. Early in the 19th century, large parks were created which represented dominant aesthetic ideals but, on the other hand, formed a ”wild” counterpart to the structured inner world of the main building. A good example is Ratula Manor and its park, which represent the diversity of the cultivated forest of the 19th century manors.
The paper is based on a lecture given in the seminar ‘The forest as a Finnish cultural entity’, held in Helsinki in 1986. The PDF includes a summary in English.
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Lönnqvist,
E-mail:
bl@mm.unknown
article id 5314,
category
Article
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Four teams of two workers were time-studied in clearcutting of a cypress plantation and three teams in sulky skidding. The heart rate was recorded every 30 s. The average heartrate in timber cutting was 117.5 ± 13.4 P/min, and it was mainly dependent on worker’s working capacity. Average work load index was 41 ± 3% when working at 97% performance. The production rate was then 2.5 m3/h (crew). In sulky skidding the heart rate was lower, 106 ± 1.1 P/min, as well as the work load (WLI 30 ± 1%) and performance rating (87%). The low production rate (1.1 m3/h) (crew)) over 45 m distance is mainly due to under-dimensioned load size. The energy expenditure in timber cutting was 21.4 kJ/min and in sulky skidding 16.3 kJ/min. Daily energy expenditure was 15.0 MJ/d, and most of the timber cutters belonged to the class ”exceptionally active”.
The PDF includes an abstract in Finnish.
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Saarilahti,
E-mail:
ms@mm.unknown
-
Bakena,
E-mail:
eb@mm.unknown
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Mboya,
E-mail:
gm@mm.unknown
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Minja,
E-mail:
tm@mm.unknown
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Ngerageze,
E-mail:
tn@mm.unknown
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Ntahompagaze,
E-mail:
jn@mm.unknown
article id 5310,
category
Article
Petri Kärenlampi.
(1987).
Puun lahonkestävyys ja kosteusdynamiikka.
Silva Fennica
vol.
21
no.
2
article id 5310.
https://doi.org/10.14214/sf.a15467
English title:
The decay resistance and moisture dynamics of wood.
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In laboratory studies the heartwood content seems to be the only natural property of a wood of different tree species influencing the decay resistance. Moistening and drying by diffusion happen quite slowly. Scots pine (Pinus sylvestris L.) sapwood takes moisture by capillary action quicker than pine heartwood and Norway spruce (Picea abies (L.) H. Karst.) wood. Swelling and shrinkage are also greatest in pine sapwood. Impregnation of pine sapwood can give it better hydrophobic and dimensional stability than that of pine heartwood.
The PDF includes an abstract in English.
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Kärenlampi,
E-mail:
pk@mm.unknown
article id 5259,
category
Article
Kari Löyttyniemi,
Olli Uusvaara.
(1986).
Further tests for termite resistance of Finnish pine heartwood.
Silva Fennica
vol.
20
no.
1
article id 5259.
https://doi.org/10.14214/sf.a15438
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The natural resistance of Finnish-grown Pinus sylvestris L. heartwood to Macrotermitinae termites was tested in Zambia in graveyard conditions. The heartwood exhibited some natural resistance but durability was, however, far from practical immunity. There was significant tree-to-tree variation in the resistance of heartwood of P. Sylvestris.
The PDF includes a summary in Finnish.
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Löyttyniemi,
E-mail:
kl@mm.unknown
-
Uusvaara,
E-mail:
ou@mm.unknown
article id 5240,
category
Article
Pertti Harstela,
Kimmo Piirainen.
(1985).
Effect of whole-body vibration and driving a forest machine simulator on some physiological variables of the operator.
Silva Fennica
vol.
19
no.
2
article id 5240.
https://doi.org/10.14214/sf.a15419
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The influence of horizontal whole-body vibration of fairly low intensity alone and combined with the mental load and motor action typical for the forest machine drive on heart rate variability (HRV), respiration rate (RR) and heart rate (HR) was studied by testing five subjects. Horizontal vibration had an influence on HR, HRV and RR. ’Control activities’ had the most influence on RR and HRV, but some influence on HR, too. ’Moving the control devices’ (motor action) gave the same response in HR as ’control activities’, but not in HRV and RR. ’Control activities’ together with ’vibration’ had a more effect on HRV and RR than these two factors singly, but not on HR. The possibilities of using these variables in field studies are discussed.
The PDF includes a summary in Finnish.
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Harstela,
E-mail:
ph@mm.unknown
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Piirainen,
E-mail:
kp@mm.unknown
article id 5219,
category
Article
Simo Poso,
Tuomas Häme,
Raito Paananen.
(1984).
A method for estimating the stand characteristics of a forest compartment using satellite imagery.
Silva Fennica
vol.
18
no.
3
article id 5219.
https://doi.org/10.14214/sf.a15398
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The paper presents a method based on two phase sampling and applicable to forest inventories. The first phase estimates are obtained from satellite imagery and, if required, from extra material such as maps. Second phase estimates are measured in the field. The method is flexible and also applicable to compartmentwise forest inventories. The experiments were based on six study areas with 439 relascope plots. The correlation coefficients between first and second stage estimates varied largely according to the study area.
The PDF includes a summary in Finnish.
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Poso,
E-mail:
sp@mm.unknown
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Häme,
E-mail:
th@mm.unknown
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Paananen,
E-mail:
rp@mm.unknown
article id 5196,
category
Article
Simo Poso.
(1983).
Kuvioittaisen arvioimismenetelmän perusteita.
Silva Fennica
vol.
17
no.
4
article id 5196.
https://doi.org/10.14214/sf.a15179
English title:
Basic features of forest inventory by compartments.
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The concepts of the terms compartment and compartment-wise forest inventory have been studied empirically by repeated delineation and intensive systematic plot samples. The material consisted of 16 study areas of some 8–90 hectares in size in Southern Finland and of more than 1,000 relascope plots. Stands and compartments were found to be rather heterogenous. Alternative photographs, working techniques and test persons were studied. An endeavour for better accuracy in compartment inventories is recommended.
The PDF includes a summary in English.
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Poso,
E-mail:
sp@mm.unknown
article id 5175,
category
Article
Erkki Lipas.
(1983).
Effect of fine material fractions on the results for soil textural parameters.
Silva Fennica
vol.
17
no.
1
article id 5175.
https://doi.org/10.14214/sf.a15090
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The role played by the medium and fine silt and clay contents in determining the quartiles and the degree of stratification from a cumulative particle-size curve was studied in order to determine what time savings could be made in the sedimentation phase of soil mechanical analysis. The clay content of the samples was, in general, found to be so small that it did not affect the parameters studied. In contrast to this, the medium and fine silt content affected the lower quartile of the distribution for many soils classified as finer than medium sand. Consequently, only the omission of the determination of the clay fraction can be recommended as a time-saving measure in mechanical analysis.
The PDF includes a summary in Finnish.
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Lipas,
E-mail:
el@mm.unknown
article id 5120,
category
Article
Pentti Sepponen.
(1981).
Kivennäismaan raekoon tunnuksista ja niiden käyttökelpoisuudesta eräiden maan ominaisuuksien kuvaamiseen.
Silva Fennica
vol.
15
no.
2
article id 5120.
https://doi.org/10.14214/sf.a15061
English title:
Particle size distribution characteristics of mineral soil and their applicability for describing some soil properties.
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The particle size distribution affects several properties of the soil, thus, the ability to define the texture type of the soil as accurately as possible in field conditions is essential. The soil particle size classification devised by Atterberg (1912) is used in Finnish forestry. The study is based on a small laboratory material. The correlation between some characteristics of the soil particle size distribution, field capacity and cation exchange capacity were determined.
The particle size characteristics such as the relative proportion of different particle sizes, average particle size (Md) and parameters depicting the degree of sorting were determined. The relative proportion of soil particles below 0.06 mm correlated best with both field capacity and cation exchange capacity. Similarly, the average particle size and the degree of sorting correlated well with the field capacity and the cation exchange capacity.
The use of sorting characteristics is not well-suited to the type of soil sample material containing a high proportion of particles of varying size as was used in this material. Such characteristics are probably more easily applicable to the fine sand and sand sediments which are predominant in Finnish forest soils. The most useful particle size distribution characteristics in soils having a great variation in particle sizes were the average particle size and the relative proportion of silt and clay. Thus, the nutrient and water status of the soil can be predicted to some extent by examining the percentage of silt and clay, average particle size and the degree of sorting.
The PDF includes a summary in English.
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Sepponen,
E-mail:
ps@mm.unknown
article id 4994,
category
Article
Martti Saarilahti.
(1978).
Seismisten luotausmenetelmien soveltuvuus metsäautoteiden pohjatutkimuksiin.
Silva Fennica
vol.
12
no.
2
article id 4994.
https://doi.org/10.14214/sf.a14848
English title:
Seismic survey methods in forest road construction.
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The aim of the study was to find out the technical and economical applicability of seismic survey methods of sub-surface earth investigations in forest road planning. Two seismographs, SOIL-TEST MD 1 and BISON 1570, were tested in studyin 31 cuts and 3 gravel areas. The devices proved to be usable in field conditions. Sounding one spot costs about 75 Fmk and methods’ rentability is greatly based on the ration between expected and unexpected events, which depends on the areal geology. It is profitable to purchase the device especially if digging out of unexpected bedrock causes high costs.
The PDF includes a summary in English.
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Saarilahti,
E-mail:
ms@mm.unknown
article id 4872,
category
Article
Matti Kärkkäinen.
(1972).
Kuusen ja männyn sydänpuuosuudesta.
Silva Fennica
vol.
6
no.
3
article id 4872.
https://doi.org/10.14214/sf.a14679
English title:
The proportion of heartwood in Norway spruce (Picea abies) and Scots pine (Pinus sylvestris).
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The study deals with the variation in the proportion of heartwood in Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) both within and between stems as examined on the basis of literature. Special attention is paid to an application, in which on the basis of the diameter of pulpwood bolts, efforts are made to predict the proportion of heartwood in the total volume of bolts. It is shown that the method, even when based on homogenous material of 564 Norway spruce and Scots pine bolts, easily leads to wrong conclusions concerning the proportion of heartwood.
The PDF includes a summary in English.
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Kärkkäinen,
E-mail:
mk@mm.unknown
article id 4844,
category
Article
Kaarina Rutanen.
(1971).
Sinivuoren luonnonpuiston kasvisto ja kasvillisuus.
Silva Fennica
vol.
5
no.
2
article id 4844.
https://doi.org/10.14214/sf.a14646
English title:
Flora and vegetation of the Sinivuori Nature Park in Southern Finland.
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The Sinivuori Nature Park, located in the northeast part of the county of Häme in Southern Finland represents the rare fertile forest lands in the country, and belong partly to the so-called centre of herb‐rich forests of Häme. Sinivuori is one of the smallest nature reserves in Finland (64 ha). The detailed vegetation analysis was performed in 1969, supplemented by earlier and later observations. The area was divided into 69 one-hectare squares for the study of the flora and vegetation.
The most common rock in the park is mica schist. The pH of the soil is relatively high, in average 6.6. Thermal-time sum is 1,100–1,200. The vegetation differs to a large extent from the surrounding areas. 169 vascular plants were found in the area, some of which very rare in the area. The paper lists the plants and their abundance in the area, and the vegetation is described by the forest types. Distribution maps are presented for the species.
The PDF includes a summary in German.
-
Rutanen,
E-mail:
kr@mm.unknown
article id 4832,
category
Article
Paavo Yli-Vakkuri,
Pentti K. Räsänen.
(1971).
Siementen peittämisen ja kylvökohdan polkaisun vaikutus männyn ruutukylvön tulokseen.
Silva Fennica
vol.
5
no.
1
article id 4832.
https://doi.org/10.14214/sf.a14621
English title:
The influence of covering and tramping the seeds into the soil on the success of spot sowing of Scots pine.
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This paper reports spot sowing experiments of Scots pine (Pinus sylvestris L.). The seeds were either covered with coarse sand, tramped in the substrate or sowed without any covering, 30 seeds in each treatment in 70 replications. The site was of Vaccinium type with sandy soil. The germination percentage was 81 and 91 on the respective years. The development of seedlings was observed for 3–4 years.
The results indicate that both tramping and covering the seeds to some extent increased the number of seedlings and improved the early development. The highest numbers of seedlings were recorded in the first growing season, after which there was 23 seedlings/100 seeds in the uncovered spots, 27 seedlings in the covered spots and 31 seedlings in the tramped spots in the experiment sowed in 1965.
Mortality of the seedlings was highest between the first and second growing season, and empty spots increased with the time. There was no difference in mortality between the sowing methods, but the number of seedlings after first growing season affected the result. Under favourable conditions four seedlings per spot seemed enough to secure the survival of minimum one seedling per spot during the three first growing seasons. In poor conditions seven seedlings was needed.
The PDF includes a summary in English.
-
Yli-Vakkuri,
E-mail:
py@mm.unknown
-
Räsänen,
E-mail:
pr@mm.unknown
article id 4805,
category
Article
Peitsa Mikola.
(1969).
Etelä-afrikkalaista taimitarhatekniikkaa.
Silva Fennica
vol.
3
no.
3
article id 4805.
https://doi.org/10.14214/sf.a14593
English title:
Article review: Fundamental studies to improve production of Pinus radiata and other pines.
article id 4769,
category
Article
English title:
Time lag between final cutting and regeneration.
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The time interval between final felling and plantation means a waste of time and thus a production loss, and may lead to lush growth of ground cover and hardwood sprouts, which increases expenses in forest management. The objective of this study was to determine the length of time between final felling and artificial regeneration in private forests in the forest districts of Uusimaa-Häme in Southern Finland and Pohjois-Häme in Central Finland. The material consists of a sample of 150 plans of the 952 cutting and regeneration plans in the district of Uusimaa-Häme and a sample of 140 plans of the 1,102 plans in Pohjois-Häme.
The time lag between final cutting and seeding or planting was on average 1.4 years in Pohjois-Häme district and 0.7 years in Uusimaa-Häme. In the latter district, 56% of the logged area was regenerated in the spring immediately following the cutting, and 84% not later than in the second spring. In Pohjois-Häme, 29% of the harvested area was regenerated immediately in the first spring following cutting, and 79% not later than in the third spring following cutting.
In Pohjois-Häme, the interval was shortest in the smallest forest holdings, and longest in the largest holdings with the largest regeneration areas. The length seems to depend mainly on the size of the regeneration area. In Uusimaa-Häme district, the interval was shortest in the smallest holdings, rather short in the largest, and longest in the intermediate-size forest properties. Seeding with Scots pine (Pinus sylvestris L.) was used in almost all regeneration areas.
The forest owners had mainly carried out the regeneration work themselves. In the Pohjois-Häme area, the interval was shorter when the district forestry board regenerated the area. 35% of the regenerated areas had required supplementary planting in Pohjois-Häme, and 47% in the Uusimaa-Häme area. Supplementary planting was more common in areas regenerated later after the cutting. In Pohjois-Häme, according to the reports of the forest owners, 75% of the regenerated areas required tending during the first three years, in Uusimaa-Häme, 80%.
The PDF includes a summary in English.
-
Yli-Vakkuri,
E-mail:
py@mm.unknown
-
Autio,
E-mail:
aa@mm.unknown
-
Vehkaoja,
E-mail:
jv@mm.unknown
article id 4731,
category
Article
English title:
Scots pine seeding and planting on drained peat soils.
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This paper describes the preliminary results of Scots pine (Pinus sylvestris L.) seeding and planting trials on drained peat soils.
The results showed that a perpared peat surface was a better surface for seeding than the unprepared one. Planting of 2+1-year seedlings succeeded better than planting 1-year seedlings. Planting on the turf gave better survival than planting on the unprepared soil surface. The whole growing season was suitable time for planting Scots pine seedlings except May when the peat soil under the surface was still frozen.
Using fertilizers in connection with planting was surveyed in two ways. Mortality of seedlings increased when they were top-dressed with NPK fertilizer. Using a so-called spot fertilizing with several combinations of fertilizers resulted in K and N tending to increase the mortality of seedlings, but P decreasing mortality.
The PDF includes a summary in English.
-
Heikurainen,
E-mail:
lh@mm.unknown
-
Päivänen,
E-mail:
jp@mm.unknown
-
Seppälä,
E-mail:
ks@mm.unknown
article id 4726,
category
Article
H. Lyr,
G. Hoffmann.
(1965).
Studies on growth of roots and shoots of certain tree species.
Silva Fennica
no.
117
article id 4726.
https://doi.org/10.14214/sf.a14284
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Understanding the growth of trees is the prerequisite for meaningful forest management. Hence the studies on the ways the trees grow is important. The growth of roots and sprouts was studied by Larix leptolesis, Pinus silvestris, Betula pendula, Robinia pseudoacasia, Populus euramericana, Pseudotsuga taxifolia, Quercus borealis and some other species. The results of still ongoing experiments on pine, birch and larch are presented for root and shoot growth.
The results indicate that the amount of light or shade the tree is having plays an important role in the growth. Hence some tree species are better adapted to shade than others, there are differences in their growth depending whether they are in light or in shade.
-
Lyr,
E-mail:
hl@mm.unknown
-
Hoffmann,
E-mail:
gh@mm.unknown
article id 4618,
category
Article
Lauri Olenius.
(1951).
Ilmakuvien käyttö valtion metsätaloudessa.
Silva Fennica
no.
69
article id 4618.
https://doi.org/10.14214/sf.a14014
English title:
Use of aerial mapping in state forestry.
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Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
Forest Service begun the aerial mapping of the state forests in northern Finland in 1948. This presentation describes the state of the work, practices and methods of the work.
-
Olenius,
E-mail:
lo@mm.unknown
article id 4617,
category
Article
English title:
Aerial mapping.
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Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes the development of aerial mapping, its principles and methods. The use of aerial photographs and the costs of the method is discussed.
-
Linnamies,
E-mail:
ol@mm.unknown
article id 4579,
category
Article
Reino Kalliola.
(1942).
Pyhätunturin kansallispuiston kasvillisuudesta ja kasvistosta.
Silva Fennica
no.
59
article id 4579.
https://doi.org/10.14214/sf.a9083
English title:
Vegetation and flora in the Pyhätunturi National Park.
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The article is based on the writer’s visits in the area in 1933 and 1939. Pyhätunturi national park was established in 1938. The fell of Pyhätunturi rises up to 540 meters above the sea level, and 357 meters above the surrounding area. The soil is predominantly stony, and the rock is quartzite. The climate is continental with low rainfall. This results in a barren area, where array of plant species is limited with the exception of few gorges with fertile river valleys. The forests have remained mostly in natural state.
Vegetation is arranged in three zones: forested area, subalpine fell birch area and alpine bare top of the fell. Scots pine (Pinus sylvestris L.) forms timberline more often than Norway spruce (Picea abies (L.) H. Karst.). Coniferous forests rise up to 365 meters on the northern slopes and up to about 385 on the southern slopes of the fell. It is followed by fell birch zone (Betula tortuosa, now Betula pubescens subsp. Czerepanovii) up to about 450-475 meters on the eastern and northern slopes, and 475-490 meters on the western slopes. The most common forest site type is Empetrum-Myrtillus site type. Herb-rich spruce swamps along the rivers have highest diversity of species. The article describes the plant species found in forests, peatlands, fell birch zone and top of the fell in detail. In all 162 different vascular plant species and 16 non-indigenous species were found in the area.
The article includes an abstract in German.
-
Kalliola,
E-mail:
rk@mm.unknown
article id 4547,
category
Article
Risto Sarvas.
(1938).
Ilmavalokuvauksen merkityksestä metsätaloudessamme.
Silva Fennica
no.
48
article id 4547.
https://doi.org/10.14214/sf.a9072
English title:
Use of aerial photography in forestry.
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The article is a treatise on use of aerial photography in forestry and its prodpective applications in Finland, based on the writers visit to Techniche Hohschule Dresden in Germany and experiences in his work in Forest Service.
Optimal conditions and principals of aerial photography are described. There is potential in use of aerial photography in Finland. The terrain is relatively flat, and large areas, especially in Lapland, are inadequately mapped. However, to fulfil the current requirements for forest maps, aerial photography should be carried out as aerial stereo photography at a sufficiently large scale. At a certain scale terrain survey becomes cheaper than aerial photography.
In forestry, aerial photography cannot substitute terrain survey, but it complements it. Aerial photographs could, for instance, form a photo archive of a region or be used as a basis for planning drainage of peatlands. In research, aerial stereo photography could become a new discipline.
The article has a German summary.
-
Sarvas,
E-mail:
rs@mm.unknown
article id 4542,
category
Article
Erkki Laitakari.
(1938).
Eräitä metsän uudistamisessa huomioon otettavia näkökohtia.
Silva Fennica
no.
46
article id 4542.
https://doi.org/10.14214/sf.a13951
English title:
Forest regeneration.
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Silva Fennica issue 46 includes presentations held in professional development courses, arranged for foresters working in public administration in 1937. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes factors that should be taken into account in forest regeneration.
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Laitakari,
E-mail:
el@mm.unknown
article id 4536,
category
Article
V. K. Ahola.
(1938).
Metsän uudistumisen tarkkailusta kovilla metsämailla ja ojitetuilla soilla sekä ojien tarkkailusta.
Silva Fennica
no.
46
article id 4536.
https://doi.org/10.14214/sf.a13945
English title:
Inspection of regeneration of forests in mineral soil forests and drained peatlands and checking of ditches.
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Silva Fennica issue 46 includes presentations held in professional development courses, arranged for foresters working in public administration in 1937. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.
This presentation describes inspection of forest regeneration of mineral soil forest types and drained peatlands, and inspection of ditches.
-
Ahola,
E-mail:
va@mm.unknown
article id 4522,
category
Article
English title:
Vegetation in Muhkuri experimental area in southwest Finland.
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A vegetation analysis was performed in Muhkuri experimental area of the Forest Research Institute. The area is located in southwest Finland near city of Turku. The dominant tree species of the area is oak (Quercus robur L.) which can be found in all the area. Common woody species are also aspen (Populus tremula L.), mountain ash (Sorbus aucuparia L.), hazel (Corylus avellana L.), juniper (Juniperus communis L.) and mountain currant (Ribes alpinum L.). A total of 198 vascular plants were found in the area, 34 of which were common in most parts of the area. Typical vegetation of different parts of the area is described. Finally, a list of all plant species is presented in the article.
The PDF includes a summary in German.
-
Auer,
E-mail:
aa@mm.unknown
article id 4479,
category
Article
L. E. T. Borg.
(1936).
Hankikylvöt Tuomarniemen hoitoalueessa vv. 1913-1930.
Silva Fennica
no.
38
article id 4479.
https://doi.org/10.14214/sf.a9065
English title:
Areas broadcast sown on snow in Tuomarniemi district in Finland in 1913-1930.
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Broadcast sowing on snow was relatively new method in the beginning of the 20th century in Finland, and the experiences of regeneration were diverse. The aim of the survey was to study the success rate of regeneration in the oldest and largest areas regenerated with this sowing method in Tuomarniemi district. Scots pine (Pinus sylvestris L.) was the most common tree species, but also Norway spruce (Picea abies (L.) H. Karst.) and European larch (Larix decidua Mill.) were used in broadcast sowing on snow.
According to the study, the success of broadcast sowing on snow was as good as patch sowing and sowing in furrows in the sites typical for Tuomarniemi. The regeneration areas were often drained peatlands or paludified lands. When sowing is done using Norway spruce seeds, site preparation either by broadcast burning or scalping with hoe is recommended. Mixed sowing with pine and spruce seldom succeeded due to the differences in site requirements of the species and growth of seedlings. Sowing of Scots pine succeeded well on the drained peatlands. Sowing should be done some years after draining to let the peat dry and sink. Site preparation is needed in sites growing Polytrichum-moss. Broadcast burned areas larger than 10 hectares seemed to regenerate poorer than sites in average, possibly due to dryness of the sites. Trials with European larch were successful, and the growth of the seedlings acceptable despite the sites being relatively poor for the species.
The PDF includes a summary in German.
-
Borg,
E-mail:
lb@mm.unknown
article id 4455,
category
Article
O Tähtinen.
(1930).
Katsaus Jokioisten kartanon eli n.s. Jokiläänin metsätalouden vaiheisiin.
Silva Fennica
no.
14
article id 4455.
https://doi.org/10.14214/sf.a8989
English title:
A short account of the history of the forestry of the Jokioinen Estate.
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The Jokioinen Estate was established in 1562 when king Erik XIV of Sweden granted a large area around Jokioinen in the southwest Finland to Klas Kristersson Horn. The estate had several landlords until it was acquired in 1872 by Jokkis Stock Company, and finally sold to the government in 1918. The forestry of the estate was influenced by complications concerning the ownership of the land. A part of the tenants of the estate had originally been independent and owned their farms, but some farms were so-called family-right-farms, which were inherited from father to son, but the farmer did not own the land. A third type of farmers were ordinary tenants, who were directly dependent on the landlord. Especially ambiguous was the family-right-farmers’ right to harvest timber from the forests. The Finnish government acquired the estate to solve the problems and gave the tenants right to buy their farms.
Until the 18th century most of the farmers in Jokioinen area practiced shifting cultivation. This method of farming influenced strongly the forests, and continued until the increased market price of timber made it unprofitable. The forests were also the source of fuel wood for both the farmers and the landlord. The estate had own saw-mill industry since the 18th century. In 1871 a trained forester was hired for the estate. When the government acquired the estate, it comprised 32,000 hectares of land. The state retained 7,000 hectares of the forests. They were managed by a trained forester and administrated under the Board of Agriculture.
The PDF includes a summary in English.
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Tähtinen,
E-mail:
ot@mm.unknown
Category :
Article
article id 7178,
category
Article
Matti Keltikangas,
Pekka Tiililä.
(1968).
Koivun ja kuusen istutuksen keskinäinen edullisuusjärjestys käenkaali-mustikkatyypin metsämailla.
Acta Forestalia Fennica
vol.
82
no.
5
article id 7178.
https://doi.org/10.14214/aff.7178
English title:
The economic sequence of silver birch (Betula pendula) and Norway spruce (Picea abies) when planting Oxalis-Myrtillus type forest land.
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The present study proposes to calculate the economic sequence of two of Finland’s three main tree species, Norway spruce (Picea abies (L.) H. Karst.) and silver birch (Betula pendula Roth) when planted on Oxalias-Myrtillus type sites where both species are equally suitable, on biological grounds. In addition, the accuracy and applicability of the present Finnish yield tables to an economic comparison is tested. Benefit/cost ratio was selected as criterion of profitableness. All future net incomes and costs were discounted into the planting time and added together. The ratio between the discounted net revenues and the discounted investment costs (later called profit ratio) was the criterion. There is no reliable method to forecast the future wood prices, therefore two price ratios, birch veneer timber to spruce pulpwood and birch cordwood to spruce pulpwood, were chosen as free variables. The economic sequence of the tree species was determined as the function of these variables.
The main conclusions are, first, that under the present price ratios spruce appears to be the better choice for the forest owner, and the most promising policy for changing the situation seems to decrease the production costs of plants in birch nurseries. Second, the present Finnish yield tables are not consistent or accurate enough to enable any sufficiently reliable economic comparisons of tree species in artificial regeneration. The possible error of difference between two rather uncertain estimates is big. More work is needed to construct a uniform system of yield tables covering all main tree species, all site types, all macro climate conditions and all types of regeneration.
The PDF includes a summary in English.
-
Keltikangas,
E-mail:
mk@mm.unknown
-
Tiililä,
E-mail:
pt@mm.unknown
article id 7174,
category
Article
Pentti Alho.
(1967).
Pohjois-Pohjanmaan rannikkokuntien maanjako-olot metsätalouden kannalta.
Acta Forestalia Fennica
vol.
82
no.
1
article id 7174.
https://doi.org/10.14214/aff.7174
English title:
Influences of partitioning of land in forestry in the municipalities of northern Ostrobothnia in Finland.
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Farm forestry in northern Ostrobothnia has met different kinds of obstacles that decrease its profitability, some national, some local. One of the later is partitioning of land. The purpose of this investigation was to survey the division of farm land in the coastal municipalities of northern Ostrobothnia in Finland, where the conditions are among the most unfavourable in the country in this respect. The material used in the investigation was collected in a previous study about the structure of the farms in the area. First part of the paper summarises the history of partitioning of land in Finland.
The results show that division of the woodlots of a farm are in the coastal municipalities of northern Ostrobothnia very disadvantageous for forestry. The average distance of a woodlot to the farmhouse is 8.3 km, but there is a great variation between the municipalities, and the distance varies from 30 to 1.9 km. The form of the lots, as the long ribbon-like woodlots in the municipality of Liminka, complicates often practical forestry. In addition, the number of separate woodlots is high, in average 9.2 per farm.
The great distance of the woodlots from the main farms hinders the use of forests and diminishes the financial result of forestry. Unfavourable form of the woodlots posts similar hindrances to harvesting of timber and forest management as the long distances and high number of separate plots. The problem is heightened by the abundance of peatlands in relation to productive forest lands in the area.
The PDF includes a summary in German.
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Alho,
E-mail:
pa@mm.unknown
article id 7129,
category
Article
Erkki K. Kalela.
(1961).
Natural regeneration of agricultural lands in so-called Porkkala-area of leased land.
Acta Forestalia Fennica
vol.
74
no.
2
article id 7129.
https://doi.org/10.14214/aff.7129
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The size of the field and the ditching on it as well as the condition of the field at the time of the surrender of Porkkala area (from Finland to Russia) play an important role on how far the natural regeneration of the fields has progressed.
Larger open fields have naturally regenerated only on sides where the surrounding forest can spread the seeds or the thicket of saplings has reached, whereas small parcels of fields have normally been fully forested. Most important species have been e.g. silver birch and pubescent birch, grey and common alders and European aspen as well as pine and spruce. The broad leaved species are dominant.
The PDF contains a summary in Finnish.
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Kalela,
E-mail:
ek@mm.unknown
article id 7362,
category
Article
Olavi Linnamies.
(1942).
Metsätalouskartaston soveltaminen sotilastarkoituksiin.
Acta Forestalia Fennica
vol.
50
no.
9
article id 7362.
https://doi.org/10.14214/aff.7362
English title:
Use of forest maps in military purposes in Finland.
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The Second World War revealed some weaknesses that affect also peacetime planning of military defence in Finland. One of the shortages were lack of maps applicable in military purposes in Northern Finland.
The state forests are mainly situated in the north. Consequently, cartographic material of Finnish Forest Service may be modified with little extra work for military purposes. Best suited for the purpose are forestry maps of different forest districts that have scales ranging from 1:20,000 to 1:100,000. In addition, general maps in the scale of 1:100,000 or 1:200,000 are available. The article discusses further the additions that can be made in the maps.
The PDF includes a summary in German.
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Linnamies,
E-mail:
ol@mm.unknown
article id 7354,
category
Article
P. S. Tikka.
(1940).
Puiden vikanaisuuksien merkitys ja huomioon ottaminen Perä-Pohjolan mäntymetsien hoidossa.
Acta Forestalia Fennica
vol.
50
no.
1
article id 7354.
https://doi.org/10.14214/aff.7354
English title:
The effect of injuries in trees on forest management of Scots pine stands in Northern Finland.
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The aim of the study was to find out what are the causes of damage in Scots pine (Pinus sylvestris L.) stands and the frequency of different kinds of injuries, which are then discussed in relation to the silvicultural state and management of the stands in comparison to ideal forests. Sample plots were studied in over 80-year old Scots pine dominated stands in mineral soil sites of different forest types in Northern Finland in the area of Perä-Pohjola. 10–40 trees were chosen as sample trees in each sample plot. The sample trees were felled, and the diameter, height of crown and injuries outside and inside of the stem were recorded.
Length of knot-free part of the stem was higher in the dominant trees and in older age classes of the trees. The form of the stem becomes broader and rounder with the age. The crowns are, however, longer in Northern Finland compared to Southern Finland. In management of Scots pine stands, all trees diseased by Scots pine blister rust (Cronartium flaccidum) should be removed. The disease is common in Northern Finland, and the number of diseased trees increases as the stands get older. Decay was more common in trees that had fire wounds. In general, injuries decreased the length and diameter growth of the trees. From the dominant trees should only injured and diseased trees removed in the thinnigs. Codominant trees can be left to grow when spare trees are needed to replace missing dominant trees. Detailed instruction of selection of the removed trees are given for each age class.
The PDF includes a summary in German.
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Tikka,
E-mail:
pt@mm.unknown
article id 7300,
category
Article
Olli Heikinheimo.
(1934).
Metsänviljelysmenetelmiä koskevista tutkimuksista.
Acta Forestalia Fennica
vol.
40
no.
23
article id 7300.
https://doi.org/10.14214/aff.7300
English title:
Research on forest regeneration methods.
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The article is a review on the research about forest regeneration in Finland, executed in the Forest Research Institute. The climate affects the results of different regeneration methods. Thus, sample plots have been established in different parts of the country. In 1933 there was a total of 386 sample plots around the country. To compare the effect of weather conditions in the regeneration, sample plots have been established in successive years. Other conditions that affect forest regeneration are soil, forest site type, tree species, time from the felling of the stand, and tending of the seedling stand. Of the 386 sample plots 245 were planting experiments and 141 sowing experiments.
The PDF includes a summary in German.
-
Heikinheimo,
E-mail:
oh@mm.unknown
article id 7220,
category
Article
Abstract |
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The result of forest valuation depends heavily on the interest rate and hence determining the rate of interest for forest is the one of the most important tasks of forest valuation.
When defining the interest rate for forests, we need to take into account not only the common interest rate in the country, but also other factors. Those are for example the increase in timber price. By calculating the land expectation value we assume that costs for felling, regeneration and other management will rise by same percent.
The article presents the common formula of land expectation value and discusses its pros and cons. Because of the bad condition of Finnish forests, the forest valuation has not been used widely in practice and hence also the research on theme has been minor. The development of the forests in future will make the theme more relevant.
The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.
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Heikkilä,
E-mail:
th@mm.unknown
article id 7074,
category
Article
Aimo Kaarlo Cajander.
(1923).
Cultivation of exotic tree species as forestry and plant geographic problem.
Acta Forestalia Fennica
vol.
24
no.
1
article id 7074.
https://doi.org/10.14214/aff.7074
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The distribution and occurrence of plant species, including trees, in the nature show that living and splendor of them is constrained by climatic factors. They have their minimum, optimum and maximum for the temperatures they can survive in. The tree species, at least mostly are divided into different varieties in different areas of the world so that the species are most suitable for the climatic conditions of their site.
The article presents the main climatic zones with their tree species according L. Ilvessalo and they suitability to Finland. More accurate areas of suitable species are also listed.
The referred results show that alongside the climatic conditions, the conditions of soil and relief must be taken into account when using exotic tree species for forestry purposes.
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Cajander,
E-mail:
ac@mm.unknown
article id 7071,
category
Article
Alvar Palmgren.
(1922).
Studies on vegetation characters of coniferous forests.
Acta Forestalia Fennica
vol.
22
no.
2
article id 7071.
https://doi.org/10.14214/aff.7071
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The paper deals with the ground vegetation of the barren coniferous forests of Åland Islands and seeks to describe its special vegetation characters with general features. The study is based on data collected during summers from 1918-1922 on Åland Islands. Work presents the forest types of Åland Islands classified according Cajander (1909) with their typical species.
The Ålandian coniferous forests seem to have a low number of species. This is because they are mostly old and closed, and have been developing for a long time without human induced disturbances from outside. Some changes have occurred due to forest fires. There is very few traces of non-native species in the forests. If some are found, they have not been able to regenerate or distribute widely.
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Palmgren,
E-mail:
ap@mm.unknown
article id 7070,
category
Article
Alvar Palmgren.
(1922).
About the number of species and area and the structure of vegetation.
Acta Forestalia Fennica
vol.
22
no.
1
article id 7070.
https://doi.org/10.14214/aff.7070
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The article describes the Ålandian vegetation of most typical habitats with greatest detail. The primary goal of the paper is to find out which deciduous species are native in the Åland Islands and hence can be seen as indicator plants for the living conditions. In addition to determining the native species of the Åland Islands, the study seeks to determine the human influence to the vegetation systems: which species are original, which have been introduced by agricultural activities, and how has the human activity influenced the abundance of the species.
The number of species varies from 44.1% to 79% of the total number of deciduous species. There is a close relation between the size of the area available for species and the number of species found. Because of that, there is a need to consider the abundance of the species alongside their diversity when studying the formation of vegetation systems or their habitats.
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Palmgren,
E-mail:
ap@mm.unknown
article id 7067,
category
Article
Aimo Kaarlo Cajander.
(1921).
Reflections on the evolution of the species, especially on arborescent plants.
Acta Forestalia Fennica
vol.
21
no.
3
article id 7067.
https://doi.org/10.14214/aff.7067
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The most abundant tree species occur in different variants in different geographical regions. They differ in their genetic, biological and partly also in morphological characters, however making clear difference between these subspecies is not possible. The different subspecies have developed according the respective areas' climatic and soil conditions, developing adaptive characters. These subspecies play a great role in practical forest management, since they differ in for forestry important characters, such as cold tolerance or stem form.
The subspecies hybridize with each other in areas where their distribution areas overlap. In these areas the subspecies cannot be always clearly defined.
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Cajander,
E-mail:
ac@mm.unknown
article id 7066,
category
Article
Aimo Kaarlo Cajander.
(1921).
Knowledge on immigration of plant species to Finland.
Acta Forestalia Fennica
vol.
21
no.
2
article id 7066.
https://doi.org/10.14214/aff.7066
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The article is an abridged version of an essay published in the “Lännetär” (a book published in Finnish on the occasion of the 50th birthday of Professor E. N. Setälä). The article presents the main points of the plant migration to Finland after the glacial period. The research method was based on J. A. Palmen’s work on flyways of the birds. Some results are achieved through plant paleontological studies, others rely on the current distribution of the species.
Some species, such as trees birch, spruce and pine have migrated widely in Finland and there isn’t any specific migration way to be found. Those species do not have any specific preconditions for their habitat and adapt also to barren soils. Species that require more specific habitats can migrate only through ways where those preconditions are available.
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Cajander,
E-mail:
ac@mm.unknown
article id 7536,
category
Article
Karl Oskar Elfving.
(1915).
White pine blister rust (Cronartium Peridermium Strobi Kleb) (Cronartium ribicola) found on stone pine (P. cembra) in Finland.
Acta Forestalia Fennica
vol.
4
no.
4
article id 7536.
https://doi.org/10.14214/aff.7536
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An occurrence of Cronartium Peridermium Strobi Kleb has been found in a privately owned garden in Tampere. They are found in several types of currant that the fungus uses as alternate host. The fungi have earlier been found on eastern white pine and now seemingly for the first time on stone pine.
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Elfving,
E-mail:
ke@mm.unknown
article id 7514,
category
Article
Pekka Ripatti.
(1996).
Factors affecting partitioning of private forest holdings in Finland.
Acta Forestalia Fennica
no.
252
article id 7514.
https://doi.org/10.14214/aff.7514
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Questions of the small size of non-industrial private forest (NIPF) holdings in Finland are considered and factors affecting their partitioning are analysed. This work arises out of Finnish forest policy statements in which the small average size of holdings has been seen to have negative influence on the economics of forestry. A literature survey indicates that the size of holdings is an important factor determining the costs of logging and silvicultural operations, while its influence on the timber supply is slight.
The empirical data are based on a sample of 314 holdings collected by interviewing forest owners in 1980–86. In 1990–91 the same holdings were resurveyed by means of a postal inquiry and partly by interviewing the forest owners. The principal objective was to collect data to assist in quantifying ownership factors that influence partitioning among different kinds of NIPF holdings. Thus, the mechanism of partitioning was described and a maximum likelihood logistic regression model was constructed using seven independent holding and ownership variables.
One out of four holdings had undergone partitioning in conjunction with a change in ownership, one fifth among family owned holdings and nearly a half among jointly owned holdings. The results of the logistic regression model indicate, for instance, that the odds on partitioning is about three times greater for jointly owned holdings than for family owned ones. Also, the probabilities of partitioning were estimated and the impact of independent dichotomous variables on the probability of partitioning ranged between 0.02 and 0.01. The low value of Hosmer-Lemeshow test statistics indicates a good fit of the model, and the rate of correct classification was estimated to be 88% with a cut-off point of 0.5.
The average size of holdings undergoing ownership changes decreased from 29.9 ha to 28.7 ha over the approximate interval 1983–90. In addition, the transition probability matrix showed that the trends towards smaller size categories mostly concerned the small size categories. The results can be used in considering the effects of the small size holdings for forestry and if the purpose is to influence partitioning through forest or rural policy.
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Ripatti,
E-mail:
pr@mm.unknown
article id 7513,
category
Article
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The paper examines the needs, premises and criteria for effective public participation in tactical forest planning. A method for participatory forest planning utilizing the techniques of preference analysis, professional expertise and heuristic optimization is introduced. The techniques do not cover the whole process of participatory planning, but are applied as a tool constituting the numerical core for decision support. The complexity of multi-resource management is addressed by hierarchical decision analysis which assesses the public values, preferences and decision criteria toward the planning situation. An optimal management plan is sought using heuristic optimization. The plan can further be improved through mutual negotiations, if necessary. The use of the approach is demonstrated with an illustrative example. Its merits and challenges for participatory forest planning and decision making are discussed and a model for applying it in general forest planning context is depicted. By using the approach, valuable information can be obtained about public preferences and the effects of taking them into consideration on the choice of the combination of standwise treatment proposals for a forest area. Participatory forest planning calculations, carried out by the approach presented in the paper, can be utilized in conflict management and in developing compromises between competing interests.
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Kangas,
E-mail:
jk@mm.unknown
-
Loikkanen,
E-mail:
tl@mm.unknown
-
Pukkala,
E-mail:
tp@mm.unknown
-
Pykäläinen,
E-mail:
jp@mm.unknown
article id 7681,
category
Article
Eero Nikinmaa.
(1992).
Analyses of the growth of Scots pine: matching structure with function.
Acta Forestalia Fennica
no.
235
article id 7681.
https://doi.org/10.14214/aff.7681
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A theoretical framework to analyse the growth of Scots pine (Pinus sylvestris L.) is presented. Material exchange processes and internal processes that transport, transform and consume materials are identified as the components of growth. Hierarchical system is lined out. Momentary uptake of material at a single exchange site depends on the environmental condition next to the exchange site, the internal state of the biochemical system of the plant and the structure of the plant. The internal state depends on the exchange flows over period of time and the structural growth depends on the internal state. The response of these processes to the fluxes is controlled by the genetic composition of the plant.
The theoretical framework is formulated into a mathematical model. A concept of balanced internal state was applied to describe the poorly known internal processes. Internal substrate concentrations were assumed to remain constant but tissue-specific. A linear relationship between the quantity of foliage and wood cross-sectional area was assumed to describe balanced formation of structure. The exchange processes were thus described as a function of external conditions. The stand level interactions were derived from shading and effects of root density on nutrient uptake.
The approach was tested at different levels of hierarchy. Field measurements indicated that the hypothesis of the linear relationship described well the regularities between foliage and sapwood of a tree within a stand when measured at functionally corresponding height. There was considerable variation in the observed regularities in the range of geographic occurrence of Scots pine. Model simulations gave a realistic description of stand development in Southern Finland. The same model was also able to describe growth differences in Lapland after considering the effect of growing season length in the parameter values. Simulations to South Russia indicate stronger deviation from the observed patterns.
The simulations suggest interesting features of stand development. They indicate strong variability in the distribution of carbohydrates between tree parts during stand development. Internal circulation of nutrients and the reuse of the same transport structure by various needle generations had a strong influence on the simulation results.
The PDF includes a summary in Finnish.
-
Nikinmaa,
E-mail:
en@mm.unknown
article id 7674,
category
Article
J. Ashley Selby,
Leena Petäjistö.
(1992).
Small sawmills as enterprises: a behavioural investigation of development potential.
Acta Forestalia Fennica
no.
228
article id 7674.
https://doi.org/10.14214/aff.7674
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The investigation examines the development potential of small sawmills in rural Finland. Development is defined with qualitative bias, given small sawmills’ limited possibilities for large-scale investments. Potential is defined in terms of the behavioural limitations to development. The investigation assumes that small sawmill entrepreneurial behaviour is essentially satisficing, and that the concept of bounded rationality is applicable. The empirical material concerns a random sample of 399 sawmills from all regions in Finland collected in connection with the 1990 small sawmill inventory.
Three sets of enterprise/entrepreneurial attributes are constructed using principal component analyses: i) entrepreneurial skills & organization, ii) small sawmill outlets, and iii) information attributes. Development potential is measured by employing discriminant analyses to test these attributes against four a priori sawmill classifications: i) sawmill production structure, ii) entrepreneurial development intentions, ii) sawmill operating environments, and iv) sawmilling as a livelihood. Each of these analyses contributes to an understanding of the entrepreneur-enterprise dialectic.
Based on the use of Pred’s behavioural matrix, small sawmill entrepreneurs’ quantity & quality of information and their ability to use information are examined with respect to sawmill typologies. In this way, the entrepreneur-enterprise dialectic is given a third dimension, that of the entrepreneurs’ partial space. The analysis is therefore able to examine development potential from the standpoint of an entrepreneur-enterprise-environment (partial space) trialectic.
The PDF includes a summary in Finnish.
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Selby,
E-mail:
js@mm.unknown
-
Petäjistö,
E-mail:
lp@mm.unknown
article id 7652,
category
Article
J. Ashley Selby.
(1989).
An exploratory investigation of entrepreneurial space: the case of small sawmills, North Karelia, Finland.
Acta Forestalia Fennica
no.
205
article id 7652.
https://doi.org/10.14214/aff.7652
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The investigation concerns the nature of the dialectic relationships between small-scale entrepreneurs in peripheral areas and their business environments.
The investigation is weighted towards a theoretical and philosophical examination of the ways in which the behaviours of real-world entrepreneurs relate to their business environments. The theoretical framework first examines the assumption of intended or bounded rationality, which recognizes that human beings are in possession of imperfect information and imperfect ability, so that their perceived world is only an approximation of the real world. Following this, an epistemology is sought which enables the individual entrepreneur to be considered as the creator of his own world, and to compare this private world to the shared context of a wider set of spatial and social relations. Such an epistemology is found in existential phenomenology, which is subjected to a critical review.
As an empirical case study, the investigation examines the small sawmill entrepreneurs of North Karelia, Finland. The empirical investigation examines the aspects of the small-scale entrepreneurs’ business attitudes, perceived business environments, and their ability to use business-related information. The existential man-environment dialectic is revealed by relating these attributes to the entrepreneurs’ social setting and the level of entrepreneurship as revealed by the sawmill typology.
The PDF includes a summary in Finnish.
-
Selby,
E-mail:
js@mm.unknown
article id 7641,
category
Article
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The effect of different fertilizer treatments on the invertebrate fauna on coniferous forest soil were investigated during the years 1979-83 both in field and in laboratory experiments. Fertilizers tested were urea (both alone and with P and K), ammonium nitrate and ashes. Ash-treatment was also controlled by raising the pH at the same level with Ca(OH)2.
Both ashes and urea resulted in considerable changes in the soil fauna. Nematodes, especially bacterial feeders, increased temporarily. Some families of Coleoptera invaded the urea-treated plots. Enchytraceid worms and several microarthropod species decreased, as well as the total animal biomass. Ash-treatment influenced more slowly than did urea-fertilizing, but it caused more permanent changes. Ammonium nitrate with lime had little influence in the field. All fertilizers affected more strongly when mixed with soil in laboratory. pH alone proved to explain most of the changes observed, but nitrogen as a nutrient also plays role independently of acidity.
The PDF includes a summary in Finnish.
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Huhta,
E-mail:
vh@mm.unknown
-
Hyvönen,
E-mail:
rh@mm.unknown
-
Koskenniemi,
E-mail:
ak@mm.unknown
-
Vilkamaa,
E-mail:
pv@mm.unknown
-
Kaasalainen,
E-mail:
pk@mm.unknown
-
Sulander,
E-mail:
ms@mm.unknown
Category :
Research article
article id 24044,
category
Research article
Shaohui Zhang,
Lauri Korhonen,
Timo Nummenmaa,
Simone Bianchi,
Matti Maltamo.
(2024).
How to implement the data collection of leaf area index by means of citizen science and forest gamification?
Silva Fennica
vol.
58
no.
5
article id 24044.
https://doi.org/10.14214/sf.24044
Highlights:
Citizen science and gamification are proposed for collecting in situ forest leaf area index data; LAI can be estimated by taking smartphone images of forest canopies at 57° zenith angle; Twenty smartphone images per plot are enough to obtain accurate LAI measurements; Additional images may be required in forests with dense or uneven canopy structure.
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Leaf area index (LAI) is a critical parameter that influences many biophysical processes within forest ecosystems. Collecting in situ LAI measurements by forest canopy hemispherical photography is however costly and laborious. As a result, there is a lack of LAI data for calibration of forest ecosystem models. Citizen science has previously been tested as a solution to obtain LAI measurements from large areas, but simply asking citizen scientists to collect forest canopy images does not stimulate enough interest. As a response, this study investigates how gamified citizen science projects could be implemented with a less laborious data collection scheme. Citizen scientists usually have only mobile phones available for LAI image collection instead of cameras suitable for taking hemispherical canopy images. Our simulation results suggest that twenty directional canopy images per plot can provide LAI estimates that have an accuracy comparable to conventional hemispherical photography with twelve images per plot. To achieve this result, the mobile phone images must be taken at the 57° hinge angle, with four images taken at 90° azimuth intervals at five spread-out locations. However, more images may be needed in forests with large LAI or uneven canopy structure to avoid large errors. Based on these findings, we propose a gamified solution that could guide citizen scientists to collect canopy images according to the proposed scheme.
-
Zhang,
School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, FI-80101 Joensuu, Finland
https://orcid.org/0000-0001-7876-9635
E-mail:
shaohui.zhang@uef.fi
-
Korhonen,
School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, FI-80101 Joensuu, Finland
https://orcid.org/0000-0002-9352-0114
E-mail:
lauri.korhonen@uef.fi
-
Nummenmaa,
Tampere University, Kalevantie 4, FI-33100 Tampere, Finland
https://orcid.org/0000-0002-9896-0338
E-mail:
timo.nummenmaa@tuni.fi
-
Bianchi,
Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland
https://orcid.org/0000-0001-9544-7400
E-mail:
simone.bianchi@luke.fi
-
Maltamo,
School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, FI-80101 Joensuu, Finland
https://orcid.org/0000-0002-9904-3371
E-mail:
matti.maltamo@uef.fi
article id 23001,
category
Research article
Eirik Ogner Jåstad,
Niels Oliver Nagel,
Junhui Hu,
Per Kristian Rørstad.
(2023).
The location and capacity-dependent price impacts of biofuel production and its effect on the forest industry.
Silva Fennica
vol.
57
no.
1
article id 23001.
https://doi.org/10.14214/sf.23001
Highlights:
Large biofuel units prefer regions close to transportation facilities; Forest owners are the main winners if large-scale biofuel production is established; The first production units reduce export, hence should be located at an exporting hub; Biofuel production will reduce the Norwegian export of roundwood to Sweden; Biofuel production increases the local demand and pulpwood prices.
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Forest-based biofuel stands out as a promising solution to avoid fossil emissions in parts of the transport sector. Biofuel production will need large amounts of forest biomass, collected from a large area. Roundwood is costly to transport compared with other goods. Therefore, the location of forest-based biofuel production is a crucial part of an investment decision. This study analyses the optimal location of biofuel plants in Norway and the implications for the traditional forest sector in the Nordic countries. We test different numbers of production units, different sizes of the units, and various raw materials. The study applies a partial equilibrium model that covers the Norwegian and Nordic forest sectors, with 356 regions in Norway. The results indicate that small biofuel plants have the potential to turn exporting regions into importing regions. Larger biofuel plants are suitable for areas with large harvest activity today or regions with access to harbour or timber terminals along railways. We find that forest owners close to a biofuel plant will profit the most from biofuel production. Policymakers and investors should take into account that different locations and production capacities have different impacts on the forest sectors.
-
Jåstad,
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway
https://orcid.org/0000-0002-1089-0284
E-mail:
eirik.jastad@nmbu.no
-
Nagel,
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway
https://orcid.org/0000-0002-3171-0262
E-mail:
niels.oliver.nagel@nmbu.no
-
Hu,
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway
https://orcid.org/0000-0003-0001-5993
E-mail:
junhui.hu@nmbu.no
-
Rørstad,
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway
E-mail:
per.kristian.rorstad@nmbu.no
article id 10767,
category
Research article
Semo Mogeia,
Alberto A. Manhiça,
Andrade F. Egas.
(2023).
Wood ash content variation in Eucalyptus grandis clones in Mozambique.
Silva Fennica
vol.
57
no.
1
article id 10767.
https://doi.org/10.14214/sf.10767
Highlights:
Eucalyptus grandis heartwood produces better fuel than sapwood, if assuming ash content as energy quality parameter; Younger individuals have higher ash content in sapwood, and older individuals in the heartwood; There was not significant stem end variation of ash content in heartwood and sapwood.
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The sustainability of native forests in Sub-Saharan Africa depends on the diversification of sources to generate bioenergy, and Eucalyptus spp. wood has been highlighted. However, the determination of energy quality parameters has been a challenge to enable plantation wood to generate energy. The research assessed the ash content of radial and longitudinal samples of Eucalyptus grandis (Hill) clone with different ages and growth sites. Samples were collected in three pre-established plots in the center of Mozambique. Five trees were cut down in each plot and six discs were removed from each tree. Grinded samples with <0.5 mm particle size were generated from the heartwood and sapwood of each disk to determine the ash content. Wood from 7-year-olds had a higher ash content compared to 9-year-olds. The two sample plots differed from each other in terms of wood ash content. Heartwood samples had smaller ash content than sapwood samples. In general, the ash content of the intermediate positions was lower than those from the base and top of the stem, for both radial sections. No conclusive differences were found between samples from the base and the top of the trees, indicating that the material from the top of the trees can also be used as wood fuel. Ash content can be a considerable parameter to assess the quality of the wood of Eucalyptus spp. as a fuel.
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Mogeia,
Universidade Lúrio, Faculdade de Ciências Agrárias, Departamento de Silvicultura e Maneio [Lurio University, Faculty of Agricultural Sciences, Department of Forestry and Management], Campus de Wanaango, EN733, Km 42, Unango, Niassa, Mozambique
E-mail:
smogeia@unilurio.ac.mz
-
Manhiça,
Centro de Investigação Florestal, [Forestry Research Center], Marracuene, EN1, Maputo província, Mozambique
E-mail:
albertomanhica@gmail.com
-
Egas,
Universidade Eduardo Mondlane, Faculdade de Agronomia e Engenharia Florestal, Departamento de Florestas, [Eduardo Mondlane University, Faculty of Agronomy and Forestry Engineering, Department of Forests], Av. Julius Nyerere, Maputo cidade, Mozambique
E-mail:
aegas8@gmail.com
article id 10757,
category
Research article
Silvana M.J. Sione,
Silvia G. Ledesma,
Pablo G. Aceñolaza,
Marcelo G. Wilson.
(2022).
Biomass Carbon and Nitrogen allocation in different tree species: do tree compartments and size affect C:N relationship?
Silva Fennica
vol.
56
no.
4
article id 10757.
https://doi.org/10.14214/sf.10757
Highlights:
C:N relationship variations in biomass compartments were positively correlated with N concentration and did not exhibit significant association with C; C:N ratios differed significantly among species and compartments; Only in Neltuma affinis and Vachellia caven stems C:N relationship differed among tree size.
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Tree carbon (C) and nitrogen (N) concentrations and C:N ratio are critical for understanding the elemental compositions of forests, N use efficiency, productivity and the biogeochemical cycles. We evaluate differences in C and N allocation among biomass compartments of three N‑fixing tree species of Espinal Argentine eco-region; the scaling relationship between C and N and the C:N ratio variation among compartments and tree size. Neltuma affinis (Spreng.) C.E. Hughes & G.P. Lewis, Neltuma nigra (Griseb.) C.E. Hughes & G.P. Lewis and Vachellia caven (Molina) Seigler & Ebinger plants (n = 30 for each species) were felled, grouped by stem basal diameter-based size classes and partitioned into 3 biomass compartments: stem (st), large branches (lb) and small branches + leaves, flowers and fruits (sbl). C and N concentrations were markedly influenced by species and biomass compartments. In general, sbl compartment presented more N than the st and lb, while C concentrations in Neltuma stems were the highest. Overall, no isometric C–N scaling relationships were found in different compartments. C:N variations in compartments were positively correlated with N concentrations but did not exhibit any significant association with C concentrations. C:N ratios differed significantly among species and biomass compartments. The C:N ratio for compartments ranked in an order of st > lb > sbl. C:N ratio variability in sbl was the least. Only in N. affinis and V. caven stems C:N relationship differed among tree size. Our results provide evidence of the importance of using in situ C and N concentration per main tree species and biomass compartments, to more accurate estimates of C and N stocks.
-
Sione,
National University of Entre Ríos, Faculty of Agricultural Sciences, Ruta 11 Km 10,5 (3101) Oro Verde, Entre Ríos, Argentina; CICyTTP-CONICET (National Research and Technological Investigation Council), Materi y España (3105) Diamante, Entre Ríos, Argentina
https://orcid.org/0000-0002-2119-0363
E-mail:
silvana.sione@fca.uner.edu.ar
-
Ledesma,
National University of Entre Ríos, Faculty of Agricultural Sciences, Ruta 11 Km 10,5 (3101) Oro Verde, Entre Ríos, Argentina
https://orcid.org/0000-0002-9264-1766
E-mail:
silvia.ledesma@fca.uner.edu.ar
-
Aceñolaza,
National University of Entre Ríos, Faculty of Agricultural Sciences, Ruta 11 Km 10,5 (3101) Oro Verde, Entre Ríos, Argentina; CICyTTP-CONICET (National Research and Technological Investigation Council), Materi y España (3105) Diamante, Entre Ríos, Argentina
https://orcid.org/0000-0002-5033-3466
E-mail:
pablo.acenolaza@fca.uner.edu.ar
-
Wilson,
National University of Entre Ríos, Faculty of Agricultural Sciences, Ruta 11 Km 10,5 (3101) Oro Verde, Entre Ríos, Argentina
https://orcid.org/0000-0002-1214-1041
E-mail:
wilson.marcelo@inta.gob.ar
article id 10512,
category
Research article
Highlights:
The basal area development of genetically improved birch in Sweden was modeled using a generalized algebraic difference approach; The best model fit, both graphically and statistically was delivered by the Korf base model; The analysis of realized gain trial showed a stability of relative differences in basal area between tested genotypes.
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Investing in planting genetically improved silver birch (Betula pendula Roth) in Swedish plantations requires understanding how birch stands will develop over their entire rotation. Previous studies have indicated relatively low production of birch compared to Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). This could result from using unrepresentative basic data, collected from unimproved, naturally-regenerated birch (Betula spp.) growing on inventory plots often located in coniferous stands. The objective of this study was to develop a basal area development function of improved silver birch and evaluate production over a full rotation period. We used data from 52 experiments including planted silver birch of different genetic breeding levels in southern and central Sweden. The experimental plots were established on fertile forest sites and on former agricultural lands, and were managed with different numbers of thinnings and basal area removal regimes. The model best describing total stand basal area development was a dynamic equation derived from the Korf base model. The analysis of the realized gain trial for birch showed a good stability of the early calculated relative differences in basal area between tested genotypes over time. Thus, the relative difference in basal area might be with cautious used as representation of the realized genetic gain. On average forest sites in southern Sweden, improved and planted silver birch could produce between 6–10.5 m3 ha–1 year–1, while on fertile agriculture land the average productivity might be higher, especially with material coming from the improvement program. The performed analysis provided a first step toward predicting the effects of genetic improvement on total volume production and profitability of silver birch. However, more experiments are needed to set up the relative differences between different improved material.
-
Liziniewicz,
The Forestry Research Institute of Sweden, Ekebo, SE-268 90 Svalöv, Sweden
E-mail:
mateusz.liziniewicz@skogforsk.se
-
Barbeito,
Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp, Sweden; Université de Lorraine, AgroParisTech, INRAE, UMR Silva, Nancy, France
E-mail:
ignacio.barbeito@slu.se
-
Zvirgzdins,
Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Box 49, 23053 Alnarp, Sweden
E-mail:
andis.zvirgzdins@slu.se
-
Stener,
The Forestry Research Institute of Sweden, Ekebo, SE-268 90 Svalöv, Sweden
E-mail:
lg.stener@telia.com
-
Niemistö,
Natural Resources In-stitute Finland (Luke), Natural resources, Seinäjoki, Finland
E-mail:
pentti.niemisto@luke.fi
-
Fahlvik,
The Forestry Research Institute of Sweden, Ekebo, SE-268 90 Svalöv, Sweden
E-mail:
nils.fahlvik@skogforsk.se
-
Johansson,
Tönnersjöheden Experimental Forest, SLU, Simlångsdalen, Sweden
E-mail:
ulf.johansson@slu.se
-
Karlsson,
The Forestry Research Institute of Sweden, Ekebo, SE-268 90 Svalöv, Sweden
E-mail:
curly.birch@gmail.com
-
Nilsson,
Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Box 49, 23053 Alnarp, Sweden
E-mail:
urban.nilsson@slu.se
article id 10447,
category
Research article
Marian Schönauer,
Stephan Hoffmann,
Martin Nolte,
Dirk Jaeger.
(2021).
Evaluation of a new pruning and tending system for young stands of Douglas fir.
Silva Fennica
vol.
55
no.
2
article id 10447.
https://doi.org/10.14214/sf.10447
Highlights:
Electric pruning shears combined with workflow re-organization reduced time demand for pruning; Thinning by chainsaw was more productive than using the clearing saw Husqvarna 535FBX, which on the other hand showed lower physical workload; Overall cost savings through the use of the new system were quantified at 6%.
Abstract |
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In Germany, management restrictions for Norway spruce (Picea abies (L.) H. Karst.) due to climate change lead to increasing interest in Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) as a potential substituting species. However, Douglas fir requires cost-intensive silvicultural treatments, such as periodic thinnings and, in particular, pruning. In order to improve the efficiency of such treatments, a new tending system with an adapted two-step work system was analyzed. The new system, using electric pruning shears and the backpack clearing saw Husqvarna 535FBX ‘Spacer’, was compared to the conventional three-step work system, using handsaw and chainsaw and characterized by tree selection previously conducted as an independent work step. Time and motion studies to determine productivity and costs, as well as ergonomic analysis through heart rate measurements and posture analysis were conducted. Overall, the new system was found to be more productive and to have lower costs, with 8.9 trees per scheduled system hour (4.17 € tree–1), compared to the conventional system with 8.1 trees per scheduled system hour (4.44 € tree–1). Ergonomic improvements with the new system could be mainly observed during the felling of competing trees, when the level of heart rate reserve was reduced by 9.3 percent points, compared to the conventional system. However, significant advantages in reducing unfavorable body postures expected for the ‘Spacer’ could not be confirmed. Since time savings within the new system were mainly attributed to the adaptation of workflow and the use of the electric shears during pruning, it should be considered to replace the ‘Spacer’ within the new system by light chainsaws for best results under the conditions investigated.
-
Schönauer,
Department of Forest Work Science and Engineering, University of Göttingen, Göttingen/Germany
E-mail:
marian.schoenauer@uni-goettingen.de
-
Hoffmann,
Department of Forest Work Science and Engineering, University of Göttingen, Göttingen/Germany; School of Forestry, University of Canterbury, Christchurch/New Zealand
https://orcid.org/0000-0002-8077-967X
E-mail:
stephan.hoffmann@uni-goettingen.de
-
Nolte,
Forest Education Center FBZ / State Enterprise Forestry and Timber NRW, Arnsberg/Germany
E-mail:
Martin.Nolte@wald-und-holz.nrw.de
-
Jaeger,
Department of Forest Work Science and Engineering, University of Göttingen, Göttingen/Germany
E-mail:
dirk.jaeger@uni-goettingen.de
article id 9948,
category
Research article
Juha Heiskanen,
Ville Hallikainen,
Jori Uusitalo,
Hannu Ilvesniemi.
(2018).
Co-variation relations of physical soil properties and site characteristics of Finnish upland forests.
Silva Fennica
vol.
52
no.
3
article id 9948.
https://doi.org/10.14214/sf.9948
Highlights:
Atmospheric temperature sum is related to site index H100 as a covariate;Soil pH and water retention at field capacity (FC) are also closely related to H100;Fine fraction is related to water retention at FC, soil layer and site type;Fine fraction co-varies also with temperature sum, H100 and slope.
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Physical soil properties have a marked influence on the quality of forest sites and on the preconditions for forest growth and management. In this study, water retention characteristics (WRC) and related physical soil properties in addition to vegetation coverage and tree stand data were studied at upland forest sites in Finland. Fixed and mixed models between soil and site characteristics were formed to estimate physical and hydrologic soil characteristics and the site quality with indirect co-varying variables. In the present data, the site quality index (H100) shows a high coefficient of determination in respect to the temperature sum. It is also related to soil fine fraction content, topsoil pH and water retention at field capacity. The thickness of the humus layer is predictable from the pH and cover of xeric and mesic plant species. The soil fine fraction content (clay + silt) is closely related to water retention at field capacity, the soil layer and site type, and without WRC to the temperature sum and site index and type, as well as the slope angle. The soil bulk density is related to organic matter, depth (layer) or alternatively to organic matter, slope and field estimated textural class (fine, medium, coarse). Water retention characteristics were found to be best determinable by the fine fraction content, depth and bulk density. Water content and air-filled porosity at field capacity are closely related to the fine fraction. This study provides novel models for further investigations that aim at improved prediction models for forest growth, hydrology and trafficability.
-
Heiskanen,
Natural Resources Institute Finland (Luke), Soil ecosystems, Neulaniementie 5, FI-70100 Kuopio, Finland
E-mail:
juha.heiskanen@luke.fi
-
Hallikainen,
Natural Resources Institute Finland (Luke), Applied statistical methods, Eteläranta 55, FI-96300 Rovaniemi, Finland
E-mail:
ville.hallikainen@luke.fi
-
Uusitalo,
Natural Resources Institute Finland (Luke), Forest technology and logistics, Korkeakoulunkatu 7, FI-33720 Tampere, Finland
E-mail:
jori.uusitalo@luke.fi
-
Ilvesniemi,
Natural Resources Institute Finland (Luke), Biorefinery and bioproducts, Tietotie 2, FI-02150 Espoo, Finland
E-mail:
hannu.ilvesniemi@luke.fi
article id 1714,
category
Research article
Liam Donnelly,
Olga M. Grant,
Conor O’Reilly.
(2017).
Effect of deployment-type on stem growth, biomass partitioning and crown characteristics of juvenile Sitka spruce clones.
Silva Fennica
vol.
51
no.
1
article id 1714.
https://doi.org/10.14214/sf.1714
Highlights:
Deployment x clone interactions reduced tree height and diameter growth in mixed plots for one clone; Height and diameter heterogeneity was significantly greater in mixed plots; Deployment-type significantly altered relationships between crown variables and competition was more asymmetric in mixed plots compared to monoclonal.
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Competitive interactions in clonal forestry are not well understood and this needs to be addressed to develop better deployment strategies. Eight juvenile Sitka spruce (Picea sitchensis (Bong.) Carriére) clones were grown in monoclonal and clonal mixtures in a field experiment for three years to assess the effects of genetic diversity on shoot growth, above- and below-ground biomass partitioning and crown characteristics. Shoot elongation was measured throughout the growing season, while diameter was measured twice annually in May and December. After the third year, crown silhouette area was estimated from digitised images for one ramet per plot and ramets were then destructively harvested. Deployment × clone interactions were observed for tree height and diameter with reductions observed in mixed plots. Mixed plots had significantly greater height and diameter heterogeneity and more asymmetrical competition than monoclonal plots. Results from this study demonstrate that stem growth can be significantly altered when clones are planted in multi-clonal mixtures but for most clones, deployment-type will not significantly reduce their productivity.
-
Donnelly,
UCD Forestry, University College Dublin, Belfield, Dublin 4, Ireland
E-mail:
liam.donnelly@ucdconnect.ie
-
Grant,
UCD Forestry, University College Dublin, Belfield, Dublin 4, Ireland
E-mail:
olga.grant@ucd.ie
-
O’Reilly,
UCD Forestry, University College Dublin, Belfield, Dublin 4, Ireland
E-mail:
conor.oreilly@ucd.ie
article id 1341,
category
Research article
Přemysl Humplík,
Petr Čermák,
Tomáš Žid.
(2016).
Electrical impedance tomography for decay diagnostics of Norway spruce (Picea abies): possibilities and opportunities.
Silva Fennica
vol.
50
no.
1
article id 1341.
https://doi.org/10.14214/sf.1341
Highlights:
Statistical parameters of EIT datasets with values of electrical resistance of heartwood are possible to employ in refining heartwood rot diagnostics; Sapwood proportion is decreasing as the proportion of decay on the radial cut expands; Using EIT datasets and sapwood proportion, trees with rot can be split into two groups as per proportion of decay: [< 35%] and [> 35%].
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The paper aimed at testing the potential of refining tree rot diagnostics carried out by means of electrical impedance tomography (EIT). Examined was the use of EIT datasets with electrical resistance values and sapwood proportion determined on the basis of tomograms. Making use of datasets with resistance values in EIT rot diagnostics is not a default method, although datasets stay unaffected by a fixed colour scale and subsequent subjective evaluation unlike tomograms. Tomography measurement was carried out for 27 individuals of Norway spruce (Picea abies [L.] Karst.) in two stands north-east of Brno, Czech Republic. Once felled down, radial cut-outs were sampled at the measurement site and used for localising rot and determining the extent of the area of decay. The results were subsequently compared with tomograms. EIT datasets containing values of electrical resistance found by measuring were statistically processed and compared with the extent of rot area identified within the cuts. Sapwood proportion values were also detected using the tomograms. The baseline assumption that sapwood proportion decreases as the rot area in the radial cut expands was confirmed. In trees with rot percentage to 35% approximately, sapwood proportion was exceeding 30% except one tree. In trees with rot percentage exceeding 35%, sapwood proportion was below 30%. On the basis of interpreted datasets, the trees can be split into three characteristic groups that correspond to the occurrence, extent and nature of the rot.
-
Humplík,
Mendel University in Brno, Faculty of Forestry and Wood Technology, Zemědělská 1665/3, 613 00 Brno, Czech Republic
E-mail:
premysl.humplik@mendelu.cz
-
Čermák,
Mendel University in Brno, Faculty of Forestry and Wood Technology, Zemědělská 1665/3, 613 00 Brno, Czech Republic
E-mail:
petr.cermak@mendelu.cz
-
Žid,
Mendel University in Brno, Faculty of Forestry and Wood Technology, Zemědělská 1665/3, 613 00 Brno, Czech Republic
E-mail:
tomas.zid@mendelu.cz
article id 1382,
category
Research article
Juha Laitila,
Johanna Routa.
(2015).
Performance of a small and a medium sized professional chippers and the impact of storage time on Scots pine (Pinus sylvestris) stem wood chips characteristics.
Silva Fennica
vol.
49
no.
5
article id 1382.
https://doi.org/10.14214/sf.1382
Highlights:
The storage time of pulpwood had no significant effect on particle size distribution in any chip size classes; The study confirms the knowledge that chipping time consumption is inversely proportional to engine power and grapple load size in feeding; The use of an narrower 80 mm × 80 mm sieve on Scots pine material does not seem to offer any benefit compared to a 100 mm × 100 mm sieve from the perspective of chip quality.
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The primary aim of this study was to clarify the chipping productivity and fuel consumption of tractor-powered and truck-mounted drum chippers when chipping pine pulpwood at a terminal. The secondary aim was to evaluate the impact of wood storage time on the chemical and physical technical specifications of wood chips by chipping pulpwood from eight different storage time groups, using Scots pine (Pinus sylvestris) pulpwood stems logged between 2 and 21 months previously at the terminal with the above-mentioned chippers. Thirdly, the impact of sieve mesh size on the particle size distribution of wood chips from different age groups was compared by using an 80 mm × 80 mm sieve for a tractor-powered chipper and a 100 mm × 100 mm sieve for a truck-mounted chipper. With both chippers, the chipping productivity grew as a function of grapple load weight. The average chipping productivity of the tractor-powered chipper unit was 19 508 kg (dry mass) per effective hour (E0h), and for the truck-mounted chipper the average productivity was 31 184 kg E0h–1. The tractor-powered drum chipper’s fuel consumption was 3.1 litres and for the truck-mounted chipper 3.3 litres per chipped 1000 kg (dry mass). The amount of extractives or volatiles did not demonstrate any statistically significant differences between storage time groups. The particle size distributions with both chippers were quite uniform, and the storage time of pulpwood did not have a significant effect on the particle size distribution in any chip size classes. One reason for this might be that the basic density of chipped wood was homogenous and there was no statistical difference between different storage times. The use of new sharp knives is likely to have affected chip quality, as witnessed by the absence of oversized particles and the moderate presence of fines. The use of narrower 80 mm × 80 mm sieves on Scots pine material does not seem to offer any benefit compared to 100 mm × 100 mm from the chip quality point of view.
-
Laitila,
Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland
E-mail:
juha.laitila@luke.fi
-
Routa,
Natural Resources Institute Finland (Luke), Bio-based business and industry, P.O. Box 68, FI-80101 Joensuu, Finland
E-mail:
johanna.routa@luke.fi
article id 894,
category
Research article
Heimo Karppinen,
Mika Korhonen.
(2013).
Do forest owners share the public’s values? An application of Schwartz’s value theory.
Silva Fennica
vol.
47
no.
1
article id 894.
https://doi.org/10.14214/sf.894
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The purpose of this study is to investigate the differences in value priorities between Finnish forest owners and the general public. A conclusion is drawn whether and to what extent value changes in society are reflected in forest owners’ values and objectives, and, finally, in their actual forestry behavior. In addition, the study highlights the differences in value priorities among forest owners in various demographic groups. The data set used in this study was based on a nationwide mail survey on Finnish non-industrial private forest owners conducted in 2009 and consisting of 2116 observations of forest owners. Schwartz’s value theory was a good fit for testing the value priorities of forest owners. The three most important values were benevolence, security and conformity, both among the forest owners and the public. Tradition was ranked the fourth most important value by the forest owners, but very low by the public. The forest owners ranked universalism slightly lower than the public in general. This difference was clearly greater when the female forest owners were compared to women in the whole population. The probability of a forest owner belonging to the Softies (high emphasis on universalism and benevolence) increased with age and was higher for the female owners and the owners with recreational or multiple objectives compared to the indifferent owners. The multiobjective owners and recreationists had relatively similar value profiles. The previous literature suggests that multiobjective owners are the most active forest owner group and that recreationists and indifferent owners are the most passive groups in their timber supply behavior. The relationship between values and forestry behavior thus remains ambiguous.
-
Karppinen,
Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland
E-mail:
heimo.karppinen@helsinki.fi
-
Korhonen,
Kämnerintie 7e 41, FI-00750 Helsinki, Finland
E-mail:
mika.korhonen@gmx.com
article id 44,
category
Research article
Abstract |
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Mimosa scabrella Benth. is an important native species of southern Brazil widely used for energy and promising for reforestation carbon offsets. Quantification of biomass and carbon stock is valuable for both purposes. From a forest inventory conducted in southern Brazil, data of M. scabrella were analyzed. Thirty sample trees were felled, excavated and weighed in the field and brought to laboratory for biomass and carbon determination. The total aboveground biomass represented 85% of the tree biomass, while roots corresponded to 15%. Correlation matrix of diameter at 1.3 m height (D), tree height (H) versus total and compartment biomass (P) indicated strong association between tree dimensions and biomasses. Five regression models were tested and equations were fitted to data of five biomass compartments and total tree biomass. The best fitting model for total biomass was P = –0.49361 + 0.034865 x D2H whereas for the partial biomass of the compartments was lnP = β0 + β1 x ln(D) + β2 lnH. Carbon concentration was statistically significantly different in foliage than in other compartments. Three approaches of calculating carbon stocks were evaluated and compared to actual data: 1) Estimated total biomass x weighted mean carbon concentration; 2) Estimated partial (compartment) biomass x compartment average carbon concentration; and 3) Carbon regression equations. No statistical difference was detected among them. It was concluded that biomass equations fitted in this study were accurate and useful for fuelwood and carbon estimations.
-
de Mello,
Federal University of Sergipe, Brazil
E-mail:
aadm@nn.br
-
Nutto,
Federal University of Paraná, Brazil
E-mail:
lnutto.ufpr@gmail.com
-
Weber,
Federal University of Paraná
E-mail:
ksw@nn.br
-
Sanquetta,
Carlos Eduardo Sanquetta
E-mail:
ces@nn.br
-
Monteiro de Matos,
Jorge Luis Monteiro de Matos
E-mail:
jlmdm@nn.br
-
Becker,
University of Freiburg, Institute of Forest Utilization and Work Science, Germany
E-mail:
gb@nn.de
article id 90,
category
Research article
Per Angelstam,
Kjell Andersson,
Robert Axelsson,
Marine Elbakidze,
Bengt Gunnar Jonsson,
Jean-Michel Roberge.
(2011).
Protecting forest areas for biodiversity in Sweden 1991–2010: the policy implementation process and outcomes on the ground.
Silva Fennica
vol.
45
no.
5
article id 90.
https://doi.org/10.14214/sf.90
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Swedish forest and environmental policies imply that forests should be managed so that all naturally occurring species are maintained in viable populations. This requires maintenance of functional networks of representative natural forest and cultural woodland habitats. We first review the policy implementation process regarding protected areas in Sweden 1991–2010, how ecological knowledge was used to formulate interim short-term and strategic long-term biodiversity conservation goals, and the development of a hierarchical spatial planning approach. Second, we present data about the amount of formally protected and voluntarily set aside forest stands, and evaluate how much remains in terms of additional forest protection, conservation management and habitat restoration to achieve forest and environmental policy objectives in the long-term. Third, a case study in central Sweden was made to estimate the functionality of old Scots pine, Norway spruce and deciduous forest habitats, as well as cultural woodland, in different forest regions. Finally, we assess operational biodiversity conservation planning processes. We conclude that Swedish policy pronouncements capture the contemporary knowledge about biodiversity and conservation planning well. However, the existing area of protected and set-aside forests is presently too small and with too poor connectivity. To bridge this gap, spatial planning, management and restoration of habitat, as well as collaboration among forest and conservation planners need to be improved.
-
Angelstam,
School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden
E-mail:
per.angelstam@slu.se
-
Andersson,
School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden
E-mail:
ka@nn.se
-
Axelsson,
School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden
E-mail:
ra@nn.se
-
Elbakidze,
School for Forest Management, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Skinnskatteberg, Sweden
E-mail:
me@nn.se
-
Jonsson,
Dept of Natural Science, Engineering and Mathematics, Mid Sweden University, Sundsvall, Sweden
E-mail:
bgj@nn.se
-
Roberge,
Dept of Wildlife, Fish and Environmental Studies, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, Umeå, Sweden
E-mail:
jmr@nn.se
article id 447,
category
Research article
Jim Kiser.
(2011).
Histochemical and geometric alterations of sapwood in coastal Douglas-fir following mechanical damage during commercial thinning.
Silva Fennica
vol.
45
no.
4
article id 447.
https://doi.org/10.14214/sf.447
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Histochemical and geometric alterations to sapwood in mechanically damaged Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco) trees were quantified 14 years after thinning. Discoloration and decay were measured in felled damaged and undamaged trees. Compartmentalized walls were identified and measured macroscopically. Sapwood to heartwood ratio was measured incrementally along the boles. Results showed a distinct reaction zone forming at the time of injury. Compartmentalized walls 1–3 were less distinct and heavily resinous streaking was evident in extant tissues, particularly in the axial direction. Post-damaged sapwood was burl-like for 4–6 years and tracheids contained resin-filled lumina. Damaged wood volumes were modeled by multiple regression. Wound depth, wound area, and diameter inside bark (DIB) accounted for 73% of the discolored volume (p = 0.02). DIB alone accounted for just over 55% of the response. Post-damaged sapwood averaged 15 mm (SE = 2.3 mm) greater in width on the side opposite the damage along the length of the boards. Wound area explained just over 65% of this response (p = 0.003). Sapwood area was not significantly different between damaged and control trees (p = 0.56). Results indicate that wounded Douglas-fir trees may slow conversion of sapwood to heartwood on the bole side opposite the wound, possibly as a response to maintain sapwood area necessary for physiological maintenance of the existing crown. About 19% of the lower bole volume in damaged trees was affected by discoloration and secondarily by structural changes. Reduction in value of the lower log can be as high as 19% by conventional bucking practices. Alternatives are presented to reduce the value loss to between 2.5% to 3.5%.
-
Kiser,
P.O. Box 3729, Pagosa Springs, Colorado, USA
E-mail:
jim.kiser@parelli.com
article id 116,
category
Research article
Eva-Maria Nordström,
Ljusk Ola Eriksson,
Karin Öhman.
(2011).
Multiple criteria decision analysis with consideration to place-specific values in participatory forest planning.
Silva Fennica
vol.
45
no.
2
article id 116.
https://doi.org/10.14214/sf.116
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The combination of multiple criteria decision analysis (MCDA) and participatory planning is an approach that has been applied in complex planning situations where multiple criteria of very different natures are considered, and several stakeholders or social groups are involved. The spatial character of forest planning problems adds further to the complexity, because a large number of forest stands are to be assigned different treatments at different points in time. In addition, experience from participatory forest planning indicates that stakeholders may think about the forest in terms of place-specific values rather than in forest-wide terms. The objective of this study was to present an approach for including place-specific values in MCDA-based participatory forest planning and illustrate the approach by a case study where the objective was to choose a multipurpose forest plan for an area of urban forest in northern Sweden. Stakeholder values were identified in interviews, and maps were used to capture place-specific spatial values. The nonspatial and nonplace-specific spatial values were formulated as criteria and used to build an objective hierarchy describing the decision situation. The place-specific spatial values were included in the creation of a map showing zones of different silvicultural management classes, which was used as the basis for creation of forest plan alternatives in the subsequent process. The approach seemed to work well for capturing place-specific values, and the study indicates that formalized methods for including and evaluating place-specific values in participatory forest planning processes should be developed and tested further.
-
Nordström,
Swedish University of Agricultural Sciences, Department of Forest Resource Management, Skogsmarksgränd 1, SE-901 83 Umeå, Sweden
E-mail:
eva-maria.nordstrom@slu.se
-
Eriksson,
Swedish University of Agricultural Sciences, Department of Forest Resource Management, Skogsmarksgränd 1, SE-901 83 Umeå, Sweden
E-mail:
loe@nn.se
-
Öhman,
Swedish University of Agricultural Sciences, Department of Forest Resource Management, Skogsmarksgränd 1, SE-901 83 Umeå, Sweden
E-mail:
ko@nn.se
article id 167,
category
Research article
Berit H. Lindstad,
Birger Solberg.
(2010).
Assessing national compliance with international forest policy processes – the role of subjective judgments.
Silva Fennica
vol.
44
no.
1
article id 167.
https://doi.org/10.14214/sf.167
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Several international policy processes with sustainable forest management (SFM) as a common goal have emerged during the past two decades. Based on an empirical study from Norway, this paper analyses the role of subjective judgments in assessing national compliance with three international forest policy processes, and the implications for determination of the effects of these processes. The Expanded Programme of Work on Forest Biological Diversity, the Ministerial Conference on the Protection of Forests in Europe and the United Nations Forum on Forests, including its predecessors, collectively provide more than 600 recommendations for SFM. While it is nothing new that SFM encompasses value questions, this paper is a systematic review of where in a process of assessing national compliance the role of judgments is most profound. The paper shows that the multiple objectives of the forest recommendations, references to national circumstances and provisions for stakeholder involvement lead to differing opinions about the degree of conformity between international recommendations and national situation, i.e. compliance. These differing opinions mean different prospects for the international processes to have effects, because only implementation, or active responses to international recommendations, constitutes effects. The roles of judgments and values are recommended topics for further investigation. Factors influencing how compliance is assessed, and consequently the degree to which implementation is deemed necessary, require specific attention. Due consideration to substantive and methodological choices in determining national changes and in separation of other sources of influence will provide a better basis for informed discussion of compliance with and effects of international forest-related policy processes.
-
Lindstad,
Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, Ås, Norway
E-mail:
berit.lindstad@umb.no
-
Solberg,
Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, Ås, Norway
E-mail:
bs@nn.no
article id 174,
category
Research article
Akihiro Sumida,
Taro Nakai,
Masahito Yamada,
Kiyomi Ono,
Shigeru Uemura,
Toshihiko Hara.
(2009).
Ground-based estimation of leaf area index and vertical distribution of leaf area density in a Betula ermanii forest.
Silva Fennica
vol.
43
no.
5
article id 174.
https://doi.org/10.14214/sf.174
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We developed a ground-based method for estimating leaf area index (LAI) and vertical distribution of leaf area density (LAD) for two Betula ermanii plots, combining an allometric method for tree leaf area with the MacArthur–Horn (MH) method using a portable laser rangefinder, including a correction for changes in leaf inclination angle along the vertical gradient measured with a portable digital protractor from a canopy access tower in each plot. Vertical distribution of projected leaf area density obtained by the MH method (LADMH) was transformed to relative distribution for allotting fixed LAI to different heights. Hence, we first developed an allometric method for estimating tree leaf area for LAI determination. Trunk cross-sectional area at branching height (AB) was accurately estimated (r2 = 0.97) from ground-based measurements of tree dimensions. We used this method to apply pipe model allometry between tree leaf area and AB, and estimated LAI (4.56 and 4.57 m2 m–2). We then examined how leaf inclination angle affected estimation of the vertical distribution of actual LAD. Leaf inclination angle measurements revealed that actual LAD in the upper canopy was 1.5–1.8-times higher than LADMH, because of steep leaf inclination, while the correction factor was 1.15–1.25 in the lower canopy. Due to the difference among heights, vertical distribution of LAD estimated with correction for vertical change in leaf inclination was more skewed to the upper canopy than that without correction. We also showed that error in LAD distribution can result if horizontal canopy heterogeneity is neglected when applying the MH method.
-
Sumida,
Institute of Low Temperature Science, Hokkaido University, N19W8, Sapporo 060-0819, Japan
E-mail:
asumida@lowtem.hokudai.ac.jp
-
Nakai,
International Arctic Research Center, University of Alaska Fairbanks, 930 Koyukuk Drive, P.O. Box 757340, Fairbanks, Alaska 99775-7340, USA
E-mail:
tn@nn.jp
-
Yamada,
International Meteorological & Oceanographic Consultants Co., Ltd. Kawaguchi-cho 2-6528-87, Choshi, Chiba 288-0001, Japan
E-mail:
my@nn.jp
-
Ono,
Institute of Low Temperature Science, Hokkaido University, N19W8, Sapporo 060-0819, Japan
E-mail:
ko@nn.jp
-
Uemura,
Field Science Center for Northern Biosphere, Hokkaido University, Tokuda 250, Nayoro, Hokkaido 096-0071, Japan
E-mail:
su@nn.jp
-
Hara,
Institute of Low Temperature Science, Hokkaido University, N19W8, Sapporo 060-0819, Japan
E-mail:
th@nn.jp
article id 204,
category
Research article
Gaby Deckmyn,
Bostjan Mali,
Hojka Kraigher,
Niko Torelli,
Maarten Op de Beeck,
Reinhart Ceulemans.
(2009).
Using the process-based stand model ANAFORE including Bayesian optimisation to predict wood quality and quantity and their uncertainty in Slovenian beech.
Silva Fennica
vol.
43
no.
3
article id 204.
https://doi.org/10.14214/sf.204
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The purpose of this study was to expand an existing semi-mechanistic forest model, ANAFORE (ANAlysing Forest Ecosystems), to allow for the prediction of log quality and the accompanying uncertainty as influenced by climate and management. The forest stand is described as consisting of trees of different cohorts, either of the same or of different species (deciduous or coniferous). In addition to photosynthesis, transpiration, total growth and yield, the model simulates the daily evolution in vessel biomass and radius, parenchyma and branch development. From these data early and latewood biomass, wood tissue composition, knot formation and density are calculated. The new version presented here, includes the description of log quality, including red heart formation of beeches. A Bayesian optimisation routine for the species parameters was added to the stand model. From a given range of input parameters (prior), the model calculates an optimised range for the parameters (posterior) based on given output data, as well as an uncertainty on the predicted values. A case study was performed for Slovenian beech forests to illustrate the main model functioning and more in particular the simulation of the wood quality. The results indicate that the ANAFORE model is a useful tool for analyzing wood quality development and forest ecosystem functioning in response to management, climate and stand characteristics. However, the Bayesian optimization showed that the remaining uncertainty on the input parameters for the chosen stand was very large, due to the large number of input parameters in comparison to the limited stand data.
-
Deckmyn,
Research Group Plant and Vegetation Ecology, University of Antwerpen, Universiteitsplein 1, 2610 Antwerpen, Belgium
E-mail:
gaby.deckmyn@ua.ac.be
-
Mali,
Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana, Slovenia
E-mail:
bm@nn.si
-
Kraigher,
Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana, Slovenia
E-mail:
hk@nn.si
-
Torelli,
Slovenian Forestry Institute, Vecna pot 2, 1000 Ljubljana, Slovenia
E-mail:
nt@nn.si
-
Op de Beeck,
Research Group Plant and Vegetation Ecology, University of Antwerpen, Universiteitsplein 1, 2610 Antwerpen, Belgium
E-mail:
modb@nn.be
-
Ceulemans,
Research Group Plant and Vegetation Ecology, University of Antwerpen, Universiteitsplein 1, 2610 Antwerpen, Belgium
E-mail:
rc@nn.be
article id 201,
category
Research article
Rui Qi,
Véronique Letort,
Mengzhen Kang,
Paul-Henry Cournède,
Philippe de Reffye,
Thierry Fourcaud.
(2009).
Application of the GreenLab model to simulate and optimize wood production and tree stability: a theoretical study.
Silva Fennica
vol.
43
no.
3
article id 201.
https://doi.org/10.14214/sf.201
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The GreenLab model was used to study the interaction between source-sink dynamics at the whole tree level, wood production and distribution within the stem, and tree mechanical stability through simulation and optimization. In this first promising numerical attempt, two GreenLab parameters were considered in order to maximize wood production: the sink strength for cambial growth and a coefficient that determines the way the biomass assigned to cambial growth is allocated to each metamer, through optimization and simulation respectively. The optimization procedure that has been used is based on a heuristic optimization algorithm called Particle Swarm Optimization (PSO). In the first part of the paper, wood production was maximized without considering the effect of wood distribution on tree mechanical stability. Contrary to common idea that increasing sink strength for cambial growth leads to increasing wood production, an optimal value can be found. The optimization results implied that an optimal source and sink balance should be considered to optimize wood production. In a further step, the mechanical stability of trees submitted to their self weight was taken into account based on simplified mechanical assumptions. Simulation results revealed that the allocation of wood at the stem base strongly influenced its global deformation. Such basic mechanical criterion can be an indicator of wood quality if we consider further the active biomechanical processes involved in tree gravitropic responses, e.g. formation of reaction wood.
-
Qi,
Ecole Centrale Paris, Laboratory of Applied Mathematics, Grande Voie des Vignes, 92295 Chatenay-Malabry, France; Institute of Automation, Chinese Academy of Sciences, LIAMA/NLPR, P.O.Box 2728, Beijing, China
E-mail:
qiruitree@gmail.com
-
Letort,
Ecole Centrale Paris, Laboratory of Applied Mathematics, Grande Voie des Vignes, 92295 Chatenay-Malabry, France
E-mail:
vl@nn.fr
-
Kang,
Institute of Automation, Chinese Academy of Sciences, LIAMA/NLPR, P.O.Box 2728, Beijing, China
E-mail:
mk@nn.cn
-
Cournède,
Ecole Centrale Paris, Laboratory of Applied Mathematics, Grande Voie des Vignes, 92295 Chatenay-Malabry, France; INRIA saclay Ile-de-France, EPI Digiplant, Parc Orsay Université, 91893 Orsay cedex, France
E-mail:
phc@nn.fr
-
Reffye,
INRIA saclay Ile-de-France, EPI Digiplant, Parc Orsay Université, 91893 Orsay cedex, France; CIRAD, UMR AMAP, Montpellier, F-34000 France
E-mail:
pdr@nn.fr
-
Fourcaud,
CIRAD, UMR AMAP, Montpellier, F-34000 France
E-mail:
tf@nn.fr
article id 213,
category
Research article
Abstract |
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It is widely believed that coming into contact with forest environments is somehow beneficial to human well-being and comfort. In Japan, “Shinrin-yoku” (taking in the atmosphere of a forest) has been proposed to be a relaxation activity associated with forest recreation. The purpose of this study was to examine the physiological effects of forest recreation on the autonomic nervous activity. The subjects were twelve male university students (21.8 ± 0.8 years old). On the first day of the experiment, six subjects were sent to a forest area, and the other six to a city area. On the second day, each subject was sent to the area he did not visit on the first day as a cross check. The subjects walked (15 minutes) around their assigned areas before noon, and sat on chairs viewing (15 minutes) the landscapes of their assigned areas in the afternoon. Heart rate variability (HRV), blood pressure, and pulse rate were measured as physiological indices. Measurements were taken at the place of accommodation in the morning, before and after walking, and before and after viewing at their assigned field areas. Pulse rate, diastolic blood pressure and LF/(LF+HF) (LF – low frequency, HF – high frequency) components of HRV were significantly lower in the forest area than in the city area. HF components of HRV tended to be higher in the forest than in the city. In conclusion, the results of the physiological measurements show that forest recreation enabled effective relaxation in people, both of the mind and body.
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Park,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
bjpark@faculty.chiba-u.jp
-
Tsunetsugu,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
yt@nn.jp
-
Kasetani,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
tk@nn.jp
-
Morikawa,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
tm@nn.jp
-
Kagawa,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
tk@nn.jp
-
Miyazaki,
Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail:
ym@nn.jp
article id 211,
category
Research article
Timo Pukkala.
(2009).
Population-based methods in the optimization of stand management.
Silva Fennica
vol.
43
no.
2
article id 211.
https://doi.org/10.14214/sf.211
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In Finland, the growth and yield models for tree stands are simulation programs that consist of several sub-models. These models are often non-smooth and non-differentiable. Direct search methods such as the Hooke-Jeeves algorithm (HJ) are suitable tools for optimizing stand management with this kind of complicated models. This study tested a new class of direct search methods, namely population-based methods, in the optimization of stand management. The tested methods were differential evolution, particle swarm optimization, evolution strategy, and the Nelder-Mead method. All these methods operate with a population of solution vectors, which are recombined and mutated to obtain new candidate solutions. The management schedule of 719 stands was optimized with all population-based methods and with the HJ method. The population-based methods were competitive with the HJ method, producing 0.57% to 1.74% higher mean objective function values than HJ. On the average, differential evolution was the best method, followed by particle swarm optimization, evolution strategy, and Nelder-Mead method. However, differences between the methods were small, and each method was the best in several stands. HJ was alone the best method in 7% of stands, and a population based method in 3% (Nelder-Mead) to 29% (differential evolution) of stands. All five methods found the same solution in 18% of stands.
-
Pukkala,
University of Joensuu, Faculty of Forest Sciences, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
timo.pukkala@joensuu.fi
article id 263,
category
Research article
Aksel Granhus,
Dag Fjeld.
(2008).
Time consumption of planting after partial harvests.
Silva Fennica
vol.
42
no.
1
article id 263.
https://doi.org/10.14214/sf.263
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Partial harvesting combined with underplanting may be a means to reduce the risk of regeneration failure when e.g. unfavourable microclimatic conditions or severe damage by bark-feeding insects may be expected after clear-cutting, and to maintain or establish certain stand structures or tree species mixture. In this study, we performed time studies of manual planting with and without prior site preparation (patch scarification, inverting) in partially harvested stands of Norway spruce (Picea abies (L.) Karst.). The harvest treatments included basal area removals of approx. 35, 45, and 55%, and a patch clear-cut treatment that was assumed to provide the same conditions for planting as conventional clear-cutting. Site preparation had a much larger influence on time consumption plant–1 (main time) than the harvest treatment. The lowest time consumption was found with inverting and the highest without site preparation. The time spent on walking between planting spots increased with decreasing harvest intensity, reflecting a lower density of planted seedlings in the partially harvested stands. A corresponding increase in main time per plant only occurred after site preparation, since the time spent on clearing the planting spot (removal of logging residue and humus) on untreated plots was higher at the higher harvest strengths. The variation in time consumption attributed to the six replicate stands was large and mainly due to the difference among stands planted by different workers.
-
Granhus,
Norwegian University of Life Sciences, Dept. of Ecology and Natural Resource Management (INA), P.O.Box 5003, NO-1432 Ås, Norway
E-mail:
aksel.granhus@umb.no
-
Fjeld,
Swedish University of Agricultural Sciences, Dept. of Forest Resource Management, SE-901 83 Umeå, Sweden
E-mail:
df@nn.se
article id 302,
category
Research article
Gökay Nemli,
Turgay Akbulut,
Emir Zekoviç.
(2007).
Effects of some sanding factors on the surface roughness of particleboard.
Silva Fennica
vol.
41
no.
2
article id 302.
https://doi.org/10.14214/sf.302
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Effects of the grit sizes of the sand belt, feeding speed and the feed power of the heads of the sander on the surface roughness of the particleboard panels were investigated. Two surface roughness parameters, average roughness (Ra) and mean peak-to-valley height (Rz), obtained from board surfaces were used in the analysis. Sanding factors were found to have a significant effect on the surface roughness of the particleboard. Better results were obtained with 40 m/min of feeding speed, 40-60-80-120 of grit sizes, and 67 kW of the feed power of the heads of the sander.
-
Nemli,
Karadeniz Technical University, Faculty of Forestry, Trabzon-Türkiye
E-mail:
nemli@ktu.edu.tr
-
Akbulut,
Istanbul University, Faculty of Forestry, Istanbul-Türkiye
E-mail:
ta@nn.tr
-
Zekoviç,
Starwood Forest Product Company, Production Manager, Bursa-Türkiye
E-mail:
ez@nn.tr
article id 323,
category
Research article
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Democratic societies’ emphasis on individual rights and freedoms inevitably opens them up to political disputes. Conflict management should thus be seen as an integral part of democratic institutional design. The evolution and management of policy disputes concerning the use of different natural resources in Finland is analysed by using the theoretical models of frame analysis and strategic interaction. The studied disputes include lake fisheries, watercourse regulation, reindeer herding, and forestry. The institutional design in the case studies varies. Despite the differences, many common features are identified that could explain their successes or difficulties in achieving sustainable and cooperative use of the resources. Among these are problems involving complex and uncertain knowledge, differences in frames held by multiple users of a resource, and distrust between the users and other parties. The analysis concludes with preliminary conclusions on how various disputes related to sustainable resource use could be managed. These include addressing the knowledge and frame problems in order to initiate a learning process; establishing sub-processes in which mutual trust between the parties – including a managing authority or a third party – can emerge; giving explicit roles and a clear division of entitlement to the parties; and providing a credible alternative for co-operation that affects the parties’ payoff assessments during the process. Finally, the conflict management process shouldn’t be regarded as a distinct phase of dispute resolution, but as an essential aspect of ongoing co-management practices of resource use.
-
Kyllönen,
Department of Social and Moral Philosophy, P.O. Box 9, FI-00014 University of Helsinki, Finland
E-mail:
simo.kyllonen@helsinki.fi
-
Colpaert,
University of Joensuu, Department of Geography, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
ac@nn.fi
-
Heikkinen,
Taida, P.O. Box 1000, FI-90014 University of Oulu, Finland
E-mail:
hh@nn.fi
-
Jokinen,
Finnish Forest Research Institute, Kolari Research Unit, Muoniontie 21 A, FI-95900 Kolari, Finland
E-mail:
mj@nn.fi
-
Kumpula,
Finnish Game and Fisheries Research Institute, Reindeer Research Station, Toivoniementie 246, FI-99910 Kaamanen, Finland
E-mail:
jk@nn.fi
-
Marttunen,
Finnish Environment Institute, P.O. Box 140, FI-00251 Helsinki, Finland
E-mail:
mk@nn.fi
-
Muje,
Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
E-mail:
km@nn.fi
-
Raitio,
Department of Social and Policy, University of Joensuu, P.O. Box 111, FI-80101 Joensuu, Finland
E-mail:
kr@nn.fi
article id 375,
category
Research article
Edgar Víquez,
Diego Pérez.
(2005).
Effect of pruning on tree growth, yield, and wood properties of Tectona grandis plantations in Costa Rica.
Silva Fennica
vol.
39
no.
3
article id 375.
https://doi.org/10.14214/sf.375
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Reduced plantation densities have the effect that obtaining natural pruning and stem straightness are less assured. The physiological process of self-pruning is replaced by manual pruning. Generally, plantations are denser and have more uniform spacing than natural forests. In many, if not most species, natural pruning is never a satisfactory option, even after branch senescence, if production of clear wood is a management objective. Natural pruning can only be considered on a species by species basis. This study reports on the first results of a pruning trial for Tectona grandis L.F. plantations in Costa Rica. The treatments consisted of pruning heights of 3.0, 4.0, and 5.0 meters, and the Control without pruning. Differences among treatments in DBH and total height were significant at 3.2, 5.2, and 6.1 years of age, but not at 7.3 years. Under an intensive pruning regime, a teak tree at rotation (20 years) may yield over 40% of knot-free volume (over 60% of the merchantable tree volume). Current findings open a scope for new management options, aiming at improving stem form and wood quality by means of an intensive pruning regime, without having a detrimental effect on tree growth and stand yield.
-
Víquez,
Tropical Agricultural Research and Higher Education Center (CATIE), Apartado 7170 CATIE, Turrialba, Costa Rica
E-mail:
eviquez@catie.ac.cr
-
Pérez,
Ambiente Tierra S.A., Apartado 733-2250, Tres Ríos, Cartago, Costa Rica
E-mail:
dp@nn.cr
article id 385,
category
Research article
Diego Pérez,
Markku Kanninen.
(2005).
Effect of thinning on stem form and wood characteristics of teak (Tectona grandis) in a humid tropical site in Costa Rica.
Silva Fennica
vol.
39
no.
2
article id 385.
https://doi.org/10.14214/sf.385
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The aim of the study was to evaluate the effects of thinning intensity on wood properties, such as heartwood proportion, wood basic density, and stem form of teak (Tectona grandis L.f.). The thinning trial was established on a teak plantation in a humid tropical site in northern Costa Rica. The moderate and heavy thinnings yielded the highest percentage of heartwood volume (25 to 30% of total stem volume). The differences between stem form factors under different treatments were not statistically significant after separating thinning effects from timing effects. Both the highest (> 0.65 g cm–3) and the lowest (< 0.50 g cm–3) wood density values were observed under light thinnings, making it difficult to establish a relationship. Large variations in wood properties found under different thinning regimes suggest that at early stages teak stands can be managed under different thinning programs without negatively affecting the quality of wood under humid tropical conditions.
-
Pérez,
Ambiente Tierra S.A., Apartado 733-2250, Tres Ríos, Cartago, Costa Rica
E-mail:
diegoperez@costarricense.cr
-
Kanninen,
Center for International Forestry Research (CIFOR), Bogor, Indonesia
E-mail:
mk@nn.id
article id 399,
category
Research article
Torjus F. Bolkesjø.
(2005).
Projecting pulpwood prices under different assumptions on future capacities in the pulp and paper industry.
Silva Fennica
vol.
39
no.
1
article id 399.
https://doi.org/10.14214/sf.399
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Capacity changes in the pulp and paper industry affect demand for pulpwood and thus pulpwood prices. This paper analyzes the impacts on roundwood prices in Norway of two possible capacity changes (one new machine and one close-down) that currently are high on the agenda in the Norwegian paper industry, and assesses the generality of the results obtained from these case studies. The two cases are implemented exogenously into a regionalized partial equilibrium forest sector model, and the capacity change scenarios are compared with a business as usual scenario assuming no demand shocks. The projected pulpwood prices change significantly in regions near mills where capacity shifts, at least for the close-down case, but only moderately at an aggregated national level. The reduction in prices under the close-down studied is higher than the price increase from the possible capacity increase case. The asymmetric price responses projected for the two case studies are supported by sensitivity analyses on other regions and cases (technologies). For the capacity increase case it is shown that the level of the projected pulpwood price is sensitive to assumptions on base-year prices and transport costs of imported roundwood, but the magnitudes of the price increases projected as a result of increased demand are less affected by these assumptions.
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Bolkesjø,
Norwegian University of Life Sciences, Dept. of Ecology and Natural Resource Management, Høyskoleveien 14, NO-1432 Ås, Norway
E-mail:
torjus.bolkesjo@umb.no
article id 525,
category
Research article
Thomas Knoke.
(2002).
Value of complete information on red heartwood formation in beech (Fagus sylvatica).
Silva Fennica
vol.
36
no.
4
article id 525.
https://doi.org/10.14214/sf.525
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Beech (Fagus sylvatica L.) is the most important deciduous tree species in Germany. The wood of beech shows normally a bright colour (white beech) as long as no coloured heartwood has been formed. The facultative heartwood formation is induced when oxygen enters central parts of older trees, where dead or at least less vital parenchyma exist. The coloured heartwood is usually called ‘red heartwood’. Beech without red heartwood can preferably be found in younger trees which show a high water content even in central parts of the stem. The presence of red heartwood is regarded as a severe reduction of timber quality. Numerous studies have investigated opportunities to derive information on the presence and characteristics of red heartwood of standing beech trees. But until now it has not been tested whether such information could be helpful to improve the economics of beech-silviculture. This paper investigates whether complete information on the heartwood of standing beech could be useful to control the proportion of discoloured timber harvested during one rotation. It is also examined, which kind of information on the heartwood could be used to improve the economic results. To verify this, simulations based on simple algorithms were conducted. The general assumption was made that all information on the heartwood would be available. The results show that information which is restricted on the mere existence of red heartwood is neither suited to significantly reduce the amount of coloured timber nor is it possible to improve economic results based on this information. Only based on information on the recent formation of red heartwood of beech, which is actually still white the amount of discoloured timber can be reduced significantly. Consequently the discounted cash flows can only be substantially improved based on information on an expected formation of recent red heartwood.
-
Knoke,
Institute of Silviculture and Forest Management, Technische Universität München, Am Hochanger 13, D-85354 Freising, Germany
E-mail:
knoke@wbfe.forst.tu-muenchen.de
article id 582,
category
Research article
Kari Kangas,
Pasi Markkanen.
(2001).
Factors affecting participation in wild berry picking by rural and urban dwellers.
Silva Fennica
vol.
35
no.
4
article id 582.
https://doi.org/10.14214/sf.582
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The purpose of this study was to examine the participation of urban and rural dwellers in the activity of berry-picking. The respondents in the study lived in the city of Joensuu and in the municipality of Ilomantsi, in eastern Finland. 68% of Joensuu households compared with 82% of those in Ilomantsi participated in berry-picking. These evident differences in the participation rates may be largely due to the higher costs incurred by urban dwellers in picking, since the probability of participation was not significantly higher for Ilomantsi households compared with those in Joensuu who had access to a summer-cottage which was likely to be located near the berry resources. In both municipalities, the participants were divided into two groups according to the nature of their participation in the activity. The larger group – termed ordinary pickers – were characteristically younger families with children, while the other group, termed active pickers, were distinctly more advanced in age. The quantities picked for home consumption by the groups of pickers in Ilomantsi were twice as large as those picked by the corresponding groups in Joensuu. In Joensuu, households were not significantly involved in commercial picking.
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Kangas,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland
E-mail:
kari.kangas@joensuu.fi
-
Markkanen,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FIN-80101 Joensuu, Finland
E-mail:
pm@nn.fi
article id 641,
category
Research article
Juha Kaitera.
(2000).
Analysis of Cronartium flaccidum lesion development on pole-stage Scots pines.
Silva Fennica
vol.
34
no.
1
article id 641.
https://doi.org/10.14214/sf.641
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Historical and current lesion development and sporulation of Cronartium flaccidum was investigated in a stand of artificially seeded pole-stage Pinus sylvestris in northern Finland. An average of 6.5 lesions developed per infected tree, most of them occurring on a minority (25%) of the trees. During the monitoring period of five years, fresh aecia appeared mainly in 7–10-year-old shoots, the age of the shoots bearing aecia varying between 3–20 years. Aecia appeared for the first time most frequently in 5–10-year-old shoots. Infection waves occurred, whereas lesions were formed most frequently in shoots formed in various years through the 1980s. After the lesions started to sporulate, sporulation in most lesions that finished sporulating during the monitoring period lasted for 1–2 years. The aecia in between 47% and 59% of the infected shoots developed annually over a longer length in proximal direction than in distal direction next to the previous year’s infection. The aecia-bearing distal part of the shoot was longer in between 19% and 37% of the shoots.
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Kaitera,
Finnish Forest Research Institute, Rovaniemi Research Station, P.O. Box 16, FIN-96301 Rovaniemi, Finland
E-mail:
juha.kaitera@metla.fi
article id 662,
category
Research article
Lars Björklund.
(1999).
Identifying heartwood-rich stands or stems of Pinus sylvestris by using inventory data.
Silva Fennica
vol.
33
no.
2
article id 662.
https://doi.org/10.14214/sf.662
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Variations in heartwood percentage, heartwood radius and sapwood width, within and between stands of Scots pine (Pinus sylvestris L.), were analysed using a database of 198 CT-scanned (computer tomography) stems from 33 research plots (stands) throughout Sweden. Heartwood percentage varied greatly both between individual trees and between stands, and correlated poorly to site, stand and tree variables. This implies that it seems unfeasible to identify heartwood-rich stands or stems, e.g., for production of heartwood products, by using inventory data. Heartwood formation expressed as the number of new heartwood rings formed each year was found to increase with increasing cambial age, from about 0.5 rings per year at a cambial age of 45 years, to about 0.8 rings per year at a cambial age of 115 years.
-
Björklund,
Swedish University of Agricultural Sciences, Department of Forest Management and Products, S-750 07 Uppsala, Sweden
E-mail:
lars.bjorklund@sh.slu.se
Category :
Research note
article id 10561,
category
Research note
Urszula Zajączkowska,
Piotr Dąbrowski,
Waldemar Kowalczuk,
Grzegorz Tarwacki.
(2022).
Leaf photosynthetic capacity, trunk wood structure and stem xylem sap flow in 700-years old Quercus robur L.: a pilot study upon oak ‘Bartek’, a natural monument in Poland.
Silva Fennica
vol.
56
no.
3
article id 10561.
https://doi.org/10.14214/sf.10561
Highlights:
Photosynthetic and hydraulic capacity of a 700-year-old Quercus robur is comparable to reference values from the literature measured in younger oak trees.
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Physiological studies of long-lived trees are particularly important at this time, especially in light of the need for trees to adapt to global climate change. The results of the present studies were obtained on an approximately 700-year-old Quercus robur L. – the ‘Bartek’ oak. The tree has to adapt to changing climatic conditions, starting from the transition between the Medieval Warm Period and the Little Ice Age, up to the present time of rapid global climate change. Tomograph imaging showed decay of the tree trunk interior and revealed that undamaged wood forms a thin layer around the trunk perimeter. Two series of experiments were carried out to assess the physiological state of the tree. The first concerned measurements related to photosynthetic capacity: chlorophyll a fluorescence, gas exchange (CO2 assimilation, transpiration), stomatal conductance and leaf water potential. The second series concerned xylem sap flow velocity and anatomical studies of stem wood. Photosynthetic capacity was within the limits reported for young healthy trees. The diurnal pattern of velocity of xylem sap flow was also typical for young vigorous trees and flow velocity correlated positively with solar radiation and negatively with air relative humidity. Anatomical observations of the outermost wood showed relatively narrow annuals rings with large diameter earlywood vessels. The results indicate that the veteran tree does not show signs of water stress probably due to a good balance of water flow and that leaf area of the canopy needs only the current ring of wood to feed transpiration of the canopy.
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Zajączkowska,
Department of Forest Botany, Warsaw University of Life Sciences - SGGW, 159 Nowoursynowska Street, 02-776 Warsaw, Poland
https://orcid.org/0000-0002-7119-7547
E-mail:
urszula_zajaczkowska@sggw.edu.pl
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Dąbrowski,
Department of Environmental Development Warsaw University of Life Sciences - SGGW, Warsaw, Poland
https://orcid.org/0000-0002-2867-8839
E-mail:
piotr_dabrowski@sggw.edu.pl
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Kowalczuk,
Ekosystem Waldemar Kowalczuk Tomasz Kowalczuk, Otwock, Poland
E-mail:
ekosystem@ekosystem.waw.pl
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Tarwacki,
Forest Protection Department, Forest Research Institute, Sękocin Las, Poland
https://orcid.org/0000-0001-5979-7788
E-mail:
G.Tarwacki@ibles.waw.pl
article id 10524,
category
Research note
Arnis Gailis,
Pauls Zeltiņš,
Roberts Matisons,
Andis Purviņš,
Juris Augustovs,
Valts Vīndedzis,
Āris Jansons.
(2021).
Local adaptation of phenotypic stem traits distinguishes two provenance regions of silver birch in Latvia.
Silva Fennica
vol.
55
no.
2
article id 10524.
https://doi.org/10.14214/sf.10524
Highlights:
Two provenance subregions in Latvia – coastal and inland – were distinguished; Silver birch populations in inland region possessed better growth, higher heritability, and phenotypic plasticity; Moderate to high heritability for stem quality was estimated in both regions; Silver birch from inland region possesses higher potential for improvement of adaptability.
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Populations of tree species with a wide geographic range, such as silver birch (Betula pendula Roth), show genetic specialization to native environments, while maintaining high phenotypical plasticity. Accordingly, assessment of local specialization is essential for adaptive management. The aim of the study was to detect geographic patterns of local adaptation of growth and stem quality based on two open-pollinated progeny trials in Latvia testing local material. Two provenance regions differing by continentality were distinguished, which also differed in genetic control of growth traits, likely originating from the post-glacial recolonization of vegetation and subsequent natural adaptation. Heritability of the traits was estimated for each of the distinguished regions, indicating differing patterns of genetic adaptation and potential for future selection. Trees from the more continental inland showed superior growth and possessed higher heritability. The coastal provenance region showed slower growth and intermediate heritability of the respective traits. Moderate to high heritability for stem quality traits was estimated irrespectively of region. Overall, better growth and higher heritability suggests that anthropogenic selection within the best inland provenances may constitute better performing and adaptable breeding population compared to the coastal one. Still, overlapping phenotypical variation and heritability of quality traits implies improved stemwood quality for plywood regardless of the provenance region. High adaptive capacity of silver birch genotypes suggests ability to cope with climatic changes, highlighting its potential for climate-smart forestry.
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Gailis,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
E-mail:
arnis.gailis@silava.lv
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Zeltiņš,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
E-mail:
pauls.zeltins@silava.lv
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Matisons,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
https://orcid.org/0000-0002-4042-0689
E-mail:
roberts.matisons@silava.lv
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Purviņš,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
E-mail:
andis.purvins@silava.lv
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Augustovs,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
E-mail:
juris.augustovs@silava.lv
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Vīndedzis,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
E-mail:
valts.vindedzis@silava.lv
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Jansons,
Latvian State Forest Research Institute Silava, 111 Rigas street, LV-2169, Salaspils, Latvia
https://orcid.org/0000-0001-7981-4346
E-mail:
aris.jansons@silava.lv
article id 310,
category
Research note
Timo Tahvanainen,
Kalle Kaartinen,
Timo Pukkala,
Matti Maltamo.
(2007).
Comparison of approaches to integrate energy wood estimation into the Finnish compartment inventory system.
Silva Fennica
vol.
41
no.
1
article id 310.
https://doi.org/10.14214/sf.310
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The harvesting of energy wood from young stands is increasing as the demand for renewable wood fuel is growing. Energy wood consists of stems, tree tops, branches and needles, depending on the size of the trees and the logging method used. The current forest inventory and planning systems used in private forests in Finland do not produce estimates of energy wood components. In stands typical for energy wood harvesting, a large share of energy wood consists of trees smaller than the minimum size for pulpwood. In this study, energy wood was included into the calculation system of compartment inventory, and a procedure for simulating the thinning treatments in young stands was developed. The results for six inventory alternatives and prediction of energy wood were compared with the use of inventory material from 37 young stands that have plenty of energy wood. The measurement of additional stand characteristics and the use of a calibration estimation method was tested, as well as the use of plot-level inventory data instead of stand level data. The results showed that the measurement of the number of trees per hectare, in addition to stand basal area and mean diameter, improved the energy wood estimates. The additional minimum and maximum diameters improved the precision of the estimates, but did not affect bias. The removal estimates were more precise when plot-level data was used, rather than stand-level data. The removal estimates were higher with plot-level data. The results suggest that, in heterogeneous young stands, plot by plot prediction would give more accurate removal estimates than the calculation of a corresponding prediction at the stand-level.
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Tahvanainen,
Finnish Forest Research Institute, P.O. Box 68, FI-80101 Joensuu, Finland
E-mail:
timo.tahvanainen@metla.fi
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Kaartinen,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuun yliopisto, Finland
E-mail:
kk@nn.fi
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Pukkala,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuun yliopisto, Finland
E-mail:
tp@nn.fi
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Maltamo,
University of Joensuu, Faculty of Forestry, P.O. Box 111, FI-80101 Joensuun yliopisto, Finland
E-mail:
mm@nn.fi
article id 653,
category
Research note
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Partial derivatives of the negative exponential, monomolecular, Mitcherlich, Gompertz, logistic, Chapman-Richards, von Bertalanffy, Weibull and the Richard’s nonlinear growth models are presented. The application of these partial derivatives in estimating the model parameters is illustrated. The parameters are estimated using the Marquardt iterative method of nonlinear regression relating top height to age of Norway spruce (Picea abies L.) from the Bowmont Norway Spruce Thinning Experiment. Formulas that provide good initial values of the parameters are specified. Clear definitions of the parameters of the nonlinear models in the context of the system being modelled are found to be critically important in the process of parameter estimation.
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Fekedulegn,
Department of Statistics, West Virginia University, Eberly College of Arts and Sciences, P.O. Box 6330, Morgantown, WV26506, USA
E-mail:
fdesta@stat.wvu.edu
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Mac Siurtain,
University College Dublin, Ireland
E-mail:
mpms@nn.ie
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Colbert,
USDA Forest Service, Northeastern Research Station, Morgantown, West Virginia
E-mail:
jjc@nn.us