Articles containing the keyword 'composition'

Distribution, biodiversity and reforestation dynamics of the platyphyllous forests in the Northwest European Russia were investigated. Data assembled from 21 landscape regions (250–350 km² each) show special features of small-leaved lime (Tilia cordata Mill., Norway maple (Acer platanoides L.), mountain elm (Ulmus glabra Mill.) and English oak (Qurecus robur L.) reforestation during the last two decades. New tendencies were found for the taiga areas with natural Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) vegetation. Natural platyphyllous reforestation in cut spruce areas poses as supposed a special question for forest management policy in the relationship to global climate changes. Feasible unsustainability of the common types of succession (Norway spruce - European birch (Betula pendula Roth); Norway spruce - European aspen (Populus tremula L.)) is discussed. Biodiversity of herbs, shrubs and tree species of platyphyllous forests is high and complex and is situated in 4–15 old-growth relics in each landscape region. Low-level genotype heterogeneity of nemoral flora species of such isolated populations is presumed. Special biodiversity conservation regulations are proposed.

• Chtchoukine, E-mail: ac@mm.unknown

The present study is the first attempt to carry out an inventory of greenhouse gas (GHG) fluxes in the forests of Estonia. The emission and uptake of CO₂ as a result of forest management, forest conversion and abandonment of cultivated lands in Estonia was estimated. The removal of GHG by Estonian forests in 1990 exceeded the release about 3.3 times. Changes in the species composition and productivity of forest sites under various simulated climate change scenarios have been predicted by using the Forest Gap Model for the central and coastal areas of Estonia. The computational examples showed that the changes in forest community would be essential.

• Mandre, E-mail: mm@mm.unknown
• Klõseiko, E-mail: jk@mm.unknown
• Reisner, E-mail: vr@mm.unknown
• Tullus, E-mail: ht@mm.unknown

The effect of species mixture was studied in a mixed stand of Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) by simulating around 100 different treatment schedules during the rotation in a naturally regenerated even-aged stand located on a site of medium fertility in North Karelia, Finland. Both thinning from below and thinning from above were applied. Optimum rotations were determined by maximising the net present value calculated to infinity and different treatment schedules were compared with the net present value over one rotation as per rotation applied. In the optimum treatment programme, the proportion of pines was decreased by half of the basal area in the first thinning stage and by the end of the rotation to about one third. In thinning from above, the proportion of pines can be maintained at a slightly higher level. It is economically profitable to maintain the growing stock capital at approximately the level recommended by Forest Centre Tapio, a semi-governmental forestry authority. With non-optimum species composition, the loss in net present value over one rotation can be about 10 % in thinning from below and about 20 % in thinning from above.

• Vettenranta, E-mail: jv@mm.unknown

The article is a literature review focusing on the reaction of soil respiration, litter decomposition and microflora of forest soils to various pollutants like acidic deposition, heavy metals and unusual high amounts of basic cations. There is a great deal of evidence indicating that environmental pollution affects soil microbial activity and community structure. Much of the data originates from experimental designs where high levels of pollutants were applied to the soil under field or laboratory conditions. Furthermore, many were short-term experiments designed to look for large effects. These experiments have an indicative value, but it has to be kept in mind that environmental pollution is a combination of many pollutants, mostly at low concentrations, acting over long periods of time. There is therefore consequently a demand for research performed in natural forest environments polluted with anthropogenic compounds. 

• Fritze, E-mail: hf@mm.unknown

Especially in forest vegetation studies, the light climate below the canopy is of great interest. In extensive forest inventories, direct measurement of the light conditions is too time-consuming. Often only the standard tree stand parameters are available. The present study was undertaken with the aim to develop methods for estimation of the light climate on the basis of readily measurable tree stand characteristics. The study material includes 40 sample plots representing different kinds of more or less mature forest stands of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.).

In each forest stand, a set of hemipherical photographs was taken and standard tree stand measurements were performed. A regression approach was applied in order to elaborate linear models for predicting the canopy coverage. The total basal area of the stand explained 63% of variance in the canopy coverage computed from hemipherical photographs. A coefficient representing the relative proportion of Norway spruce in the stand increased the explanatory power into 75%. When either the stand density (stems/unit area) or dominant age of the stand was included into the model, increment of the explanatory power into 80% was achieved. By incorporating both of the preceding predictors, an explanatory power of 85% was reached.

The PDF includes a summary in Finnish.

• Kuusipalo, E-mail: jk@mm.unknown

The amount of volatile oil and monoterpene composition in Scots pine (Pinus sylvestris L.) needles were studied in trees growing near two factories and in the city of Kuopio, Central Finland. Trees in these locations are exposed principally to sulphur dioxide and fluoride emissions.

The amount of volatile oil increased with increasing injury class in the trees growing near the fertilizer factory. The amounts of volatile oil in trees near the pulp mill differed in the various injury classes. More oil was found in younger needles. The greatest differences in monoterpene composition were in the amounts of camphene, α-pinene, myrcene and tricyclene.

The PDF includes a summary in Finnish.

• Lehtiö, E-mail: hl@mm.unknown

The aim of this project was to investigate the cellulose decomposition rate in the soil on the ecological conditions created by different tree species, particularly birch (Betula sp.) and Norway spruce (Picea abies (L.) H. Karst.). Therefore, comparable sample plots were established in adjoining birch and spruce stands. Data on the stands, the vegetation, and the soil in the sample plots were collected. The experiment was carried out in the Ruotsinkylä Experimental Forest near Helsinki in Southern Finland.

Five pieces (3x5x0.15 cm) of cellulose (bleached sulphite pulp) were dried, weighed, and fastened in a row into a nylon bag. The bags were placed into the soil at a slant so that the upmost piece of cellulose was in the depth of 0–1.5 cm and the bottom one 6–7.5 cm. The weight losses of the pieces were measured after periods ranging from 6 to 12 months.

The results show that even within the same forest type, decomposition is much more rapid in birch stands than in spruce stands. In all the stands the decomposition rate decreased rapidly with increasing depth. The difference between birch and spruce stand, as well as the decrease with increasing depth, was probably mainly due to different thermal conditions.

The PDF includes a summary in English.

• Lähde, E-mail: el@mm.unknown

Dilution plate method was used in studying the density and composition of the microfungal populations of the organic layer of Scots pine forests, and the soil-plate method in studying the part of these populations decomposing cellulose. The media used were rose bengal agar (Martin’s medium for fungi) and cellulose medium.

The microfungal density depended to a considerable extent on the moisture content and temperature of the organic layer. Only the combination of relatively high moisture content and temperature, but neither of these factors alone, influenced considerably the microfungal population density. The correlation of the populations to the changes in this combined factor was stronger than the correlation to the seasonal variations of spring, summer and autumn.

The microfungal population consisted of only a few species. Mucor, Mortierella and Penicillium were the most common genera isolated from the rose bengal agar. The first and the last of these comprised almost 90% of the total population. For the Mucor fungi, increases in the moisture content up to the maximum values found (75%) were favourable; the Penicillium fungi, on the contrary, were intolerant of high moisture content.

Among the cellulose decomposing microfungi grown on cellulose medium, Trichoderma sp. was the most common; also, it formed the most colonies, tolerated the lowest temperatures, and was most efficient. The others were of the genera Pullularia, Verticillium, Scopulariopsis and Penicillium. In addition, there were some unidentified Phycomycetes fungi. Only the two first-mentioned caused observable changes in cellulose.

• Schalin, E-mail: is@mm.unknown

The objective of this project was to determine the amount of gas exchange in peat samples collected from several swamps, using the Warburg method in the laboratory measurements. Special attention was directed on the influence of the lowering of the ground water level through drainage, on oxidation-reduction conditions in the samples from both forested and treeless peatlands, by measuring oxygen uptake and CO₂ release. The biological activity in situ was determined by the cellulose decomposition rate in the sample plots. The six areas examined were both in drained peatlands and peatlands in natural condition.

The results show that in the sample plots in open swamps there was no consistent differences in the CO₂ release rate in peat samples taken from different depths. However, in the sample plots on forested swamps rapid decrease is seen with increasing depth. The decreased biological activity of peat is caused by the oxidation-reduction conditions. The CO₂ release rate may also be due to the respiration of tree roots, which are very shallow in peatlands.

The rate of in situ cellulose decomposition experiment and CO₂ release indicated by the Warburg measurements appear to be correlated. The results indicate improved conditions for cellulose-decomposing microbes after draining. It is also possible that the biological activity of peat after draining increases to a considerable depth until the decrease of easily decomposable substances limit the activity in an old drainage area. The cellulose decomposition rate would still increase as the oxidation-reduction conditions improve.

• Lähde, E-mail: el@mm.unknown

Quantitative investigation of bacteria in the humus is needed when the intensity of their function in decomposition in the soil is studied. In this study bacterial density of humus was measured using dilution plate method, which was subjected to thorough investigation. The method was chosen, despite its complexity, because it is quite consistent, each stage can be studied separately and the reliability can be tested. The aim of the study was to determine the best way to take samples so that the sample will represent the bacterial population as closely as possible, and to optimize homogenization and dilution of the sample and the assays.

On the basis of the results of the investigation, a procedure was developed for quantitative determination of aerobic bacteria in the humus by the dilution plate method. The paper recommends that subsamples are collected systematically from at least 25 different points. The moisture and temperature of the samples should remain similar to the natural environment until preparation of the dilution. The sample was homogenized with the Bühler homogenizer, which is constructed so that a certain degree of asepsis can be maintained and the speed of the apparatus can be regulated. The content of the mineral nutrients of the sample must be determined when choosing the way of homogenization to obtain the highest number of colonies per plate. The sample was diluted with either 0.1–0.01% peptone solution or 0.5% soil extract. The most advantageous degree of dilution was obtained by testing with the aid of Fisher’s dispersion index the probability of the Poisson distribution in the results.

• Schalin, E-mail: is@mm.unknown

Decomposition of the peat using von Post Humification Scale (1–10), developed by Lennart von Post, can be determined based on characteristics of peat, such as fibre integrity, colour and viscosity of exudate, and presence of colloidal particles, of handful of peat squeezed in the hand. It is easy to use and has proved useful in the practical work. The method developed by Pjavthenko is mostly based on specific weight off a dried sample in percentage, and requires analysis in the laboratory. The aim of this study was to compare the results of these two methods by measuring 156 peat samples representing different stages of decomposition.

The methods are based on different principles, which is reflected in small differences of the results. The maximum scores of the methods are clearly in different level. The maximum grade of 9–10 in von Post scale correspond decomposition percentage 51 in the scale of Pjavtsheko. However, the decomposition values in von Post scale are placed evenly on the scale of Pjavtshenko. This suggests that the von Post Scale is consistent and accurately developed. According to the study, the Pjavtshenko method is a good method to validate results of von Post Humification Scale, and can be used when decomposition of peat samples is determined in laboratory.

The PDF includes a summary in German.

• Sarasto, E-mail: js@mm.unknown

The purpose of this investigation was to obtain a preliminary picture of the composition of the microbial population in some virgin soils on forest land in Finland. Four different forest types were studied, Oxalis-Myrtillus type birch (Betula sp.) stand, Oxalis-Myrtillus type Norway spruce (Picea abies (L.) Karst.) stand, Vaccinium type Scots pine (Pinus sylvestris L.) stand, and drained pine bog. In addition, a flood meadow was selected as a comparison.

The methods used captured only part of the fungi growing in the soil. Rapidly growing types, especially Mucor and Penicillium species, were mainly isolated. In addition, fungi showing activity of decomposition, such as Fusarium, Monosporium and Spicaria, as well as an ascomycete of the genius Ascobolus, were isolated. Autochthonous bacteria were most abundant in the soils of Oxalis-Myrtillus type forests and in the flood meadow. In the birch stand 90% of the autochthonous bacterial flora were gram-negative bacteria, in the Oxallis-Myrtillus spruce and Vaccinium type pine stand 60% were gram-negative, while the share was only 25% in the pine bog. Nitrogen-fixing bacteria of the type Clostridium pasteurianum were found in all soils. Actinomycetes were found in all sites. The numbers of protozoa were highest in the soils of Oxalis-Myrtillus type forests.

There were no big differences between the forest soils and the flood meadow. Some groups of micro-organisms seem to be absent from the forest soils, which is probably due to the more favourable pH in the meadow. The occurrence of myxobacteria is interesting since no earlier data exist of this organism in Finnish soils.

The PDF includes a summary in English.

• Gyllenberg, E-mail: hg@mm.unknown
• Hanioja, E-mail: ph@mm.unknown
• Vartiovaara, E-mail: uv@mm.unknown

Pollen analysis has given information on development of the tree species composition after the ice age, but this kind of studies have not been published in Finland. In this study, pollen analysis was performed in five peatlands in the southwest Finland. According to the analysis, the forests of the area have had similar tree species composition for many thousands of years. Scots pine (Pinus sylvestris L.) has been the dominant species as long as there has been Norway spruce (Picea abies (L.) H. Karst.) in the area. Norway spruce seems to have arrived about 4,500 years ago. It increased slowly in the beginning, and after reaching a maximum has been slowly decreasing. Before spruce arrived, Betula sp. was more abundant, and seemed to be the dominant tree species in some places. Traces of fire in the peat layers indicate that forest fires have been common before people arrived in the area, and may have beneficial to birch. Like Betula sp., also Alnus sp. were more common before spruce arrived. Also pollen of other broadleaved species, for example, Tilia sp., Ulmus sp. and Corylus could be found. However, Quercus pollen was not found. The paludification of the peatlands had begun at different times which indicates that there has not been a common cause for the development of the peatlands in the area.

The PDF includes a summary in German.

• Lukkala, E-mail: ol@mm.unknown

The aim of the study was to find out firstly whether there are differences between the etheric oils of botanically alike but in different climatic conditions growing trees, and secondly whether the oils from alike trees are also alike. This article shortly describes the chemical composition of  Pseudotsuga Douglasii cecian Schwerin and Pinus Murrayana Engelm. The needle samples are from Mustiala Arboretum.

The first mentioned contains α-pinene, camphene, bornyl acetate, probably also limonene but no geraniol. Pinus Murraya’s oil contains pinene, camphene, borneol and cadinene.

The PDF contains a summary in Finnish.  

• Komppa, E-mail: gk@mm.unknown

The aim of the present study was to collect information on biological activity in the topmost 30 cm peat layer in certain natural and drained peatlands of different fertility, covered by different stands.

The results showed that if the ground water table in peatland sites is located in the immediate vicinity of the ground surface (about 5-10 cm in depth), conditions are reducing, and often even anaerobic, up to the ground surface. By means of drainage the aerobic limit can be dropped to a greater depth. This will occur because of the aerobic limit closely follows the fluctuation of the ground water table.

Although, by means of drainage, the aerobic limit can be lowered to more than 50 cm in depth, rains are followed by a rise of a ground water table and the aerobic limit; hereby a change from oxidizing to reducing conditions takes place. Only by keeping the ground water table and the aerobic limit constantly at the depth of more than 50 cm is it possible to obtain oxidizing conditions in the topmost 20-30 cm peat layer. The anaerobic conditions prevent the tree roots penetrating deeper in the peat.

In reducing conditions cellulose decomposition as well as carbon dioxide release from peat samples is slower than in oxidizing conditions. The rate of cellulose decomposition, however, is essentially dependent on the nitrogen content and the acidity of the peat.

• Lähde, E-mail: el@mm.unknown

• Peltoniemi, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: mikko.peltoniemi@metla.fi
• Thürig, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland; European Forest Institute, Joensuu, Finland E-mail: et@nn.ch
• Ogle, Natural Resources Ecology Laboratory, Colorado State University, Fort Collins, USA E-mail: so@nn.us
• Palosuo, European Forest Institute, Joensuu, Finland E-mail: tp@nn.fi
• Schrumpf, Max-Planck-Institute for Biogeochemistry, Jena, Germany E-mail: ms@nn.de
• Wutzler, Max-Planck-Institute for Biogeochemistry, Jena, Germany E-mail: tw@nn.de
• Butterbach-Bahl, Institute for Meteorology and Climate Research, Forschungszentrum Karlsruhe GmbH, Garmisch-Partenkirchen, Germany E-mail: kbb@nn.de
• Chertov, St. Petersburg State University, St. Petersburg-Peterhof, Russia E-mail: oc@nn.ru
• Komarov, Institute of Physicochemical and Biological Problems in Soil Science of Russian Academy of Sciences, Pushchino, Russia E-mail: ak@nn.ru
• Mikhailov, Institute of Physicochemical and Biological Problems in Soil Science of Russian Academy of Sciences, Pushchino, Russia E-mail: am@nn.ru
• Gärdenäs, Dept. of Soil Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden E-mail: ag@nn.se
• Perry, USDA Forest Service, Northern Research Station, St. Paul, MN USA E-mail: cp@nn.us
• Liski, Finnish Environment Institute, Helsinki, Finland E-mail: jl@nn.fi
• Smith, School of Biological Sciences, University of Aberdeen, Aberdeen, UK E-mail: ps@nn.uk
• Mäkipää, Finnish Forest Research Institute, Vantaa Research Unit, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: raisa.makipaa@metla.fi

Carbon sequestration rates in forest soil can be estimated using the concept of calculable stable remains in decomposing litter. In a case study of Swedish forest land we estimated C-sequestration rates for the two dominant tree species in the forest floor on top of the mineral soil. Carbon sequestration rates were upscaled to the forested land of Sweden with 23 x 10⁶ ha with Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (Karst.) L.). Two different theoretical approaches, based on limit-value for litter decomposition and N-balance for vegetation and SOM gave rates of the same magnitude. For the upscaling, using these methods, 17 000 grids of 5 x 5 km were used.

The ‘limit-value approach’ gave a sequestration of 4.8   10⁶ tons of C, annually sequestered in the forest floor, with an average of 180 kg C ha^–1 yr^–1 and a range from 40 to 410 kg C ha^–1 yr^–1. The ‘N-balance approach’ gave an average value of c. 96 kg ha^–1 yr^–1 and a range from –60 to 360 kg ha^–1 yr^–1. A method based on direct measurements of changes in humus depth over 40 years, combined with C analyses gave an average rate that was not very different from the calculated rates, viz. c. 180 kg ha^–1 yr^–1 and a range from –20 to 730 kg ha^–1 yr^–1. These values agree with forest floor C sequestration rate based on e.g. sampling of chronsequences but differ from CO₂ balance measurements.

The three approaches showed different patterns over the country and regions with high and low carbon sequestration rates that were not always directly related to climate.

• Berg, Dept. of Forest Ecology, University of Helsinki, Finland (present address: Dipartimento Biologia Strutturale e Funzionale, Complesso Universitario, Monte S. Angelo, Napoli, Italy E-mail: bjorn.berg@helsinki.fi
• Gundersen, Forest & Landscape Denmark, University of Copenhagen, Denmark E-mail: pg@nn.dk
• Akselsson, Swedish Environmental Research Institute, IVL, Gothenburg, Sweden E-mail: ca@nn.se
• Johansson, Department of Forest Soils, SLU, Uppsala, Sweden E-mail: mbj@nn.se
• Nilsson, Department of Forest Soils, SLU, Uppsala, Sweden E-mail: an@nn.se
• Vesterdal, Forest & Landscape Denmark, University of Copenhagen, Denmark E-mail: lv@nn.dk

We studied the spatial decomposition rates of standardised organic substrates in soils (burned boreal pine-dominated sub-xeric forests in eastern Finland), with respect to charred and non-charred coarse woody debris (CWD). Decomposition rates of rooibos plant litter inside teabags (C:N = 42.870 ± 1.841) and pressed-sheet Nordic hardwood pulp (consisting of mainly alpha-cellulose) were measured at 0.2 m distance from 20 charred (LC0.2) and 40 non-charred logs (LNC0.2). We also measured decomposition at 60 plots located 3–10 m away from downed logs (L3,10). The rooibos decomposition rate constant ‘k’ was 8.4% greater at the LNC0.2 logs than at the L3,10 or LC0.2 logs. Cellulose decomposed more completely in 1 micron mesh bags at LNC0.2 (44% of buried bags had leftover material) than at LC0.2 (76%) or L3,10 (70%). Decomposition of cellulose material was rapid but varied greatly between sampling plots. Our results indicate that decomposition of the standardised organic matter was more rapid close to CWD pieces than further away. However, only the plots located near non-charred logs (LNC0.2) exhibited high decomposition rates, with no corresponding increase observed at the charred logs (LC0.2). This suggests a possible noteworthy indirect effect of forest burning on soil organic matter (SOM) decomposition rates close to charred CWD after forest fires. We urge for more studies on this tentative observation as it may affect the estimates on how fires affect carbon cycling in forests.

• Čugunovs, University of Eastern Finland, School of Forest Sciences, Yliopistokatu 7, P.O. Box 111, FI-80101 Joensuu, Finland E-mail: mihails.cugunovs@gmail.com
• Tuittila, University of Eastern Finland, School of Forest Sciences, Yliopistokatu 7, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0001-8861-3167 E-mail: eeva-stiina.tuittila@uef.fi
• Kouki, University of Eastern Finland, School of Forest Sciences, Yliopistokatu 7, P.O. Box 111, FI-80101 Joensuu, Finland https://orcid.org/0000-0003-2624-8592 E-mail: jari.kouki@uef.fi

Boreal forest soil contains significant amounts of organic carbon. Soil disturbance, caused for example by site preparation or stump extraction, may increase decomposition and thus lead to higher CO₂ emissions, contributing to global warming. The aim of this study was to quantify responses of soil-surface CO₂ fluxes (R_s) and litter (needle and root) decomposition rates following various kinds of soil disturbance commonly caused by mechanical site preparation and stump harvest. For this purpose four treatments were applied in a clear-cut site in central Sweden: i) removal of the humus layer and top 2 cm of mineral soil, ii) placement of a humus layer and 2 cm of mineral soil upside down on top of undisturbed soil, forming a double humus layer buried under mineral soil, iii) heavy mixing of the humus layer and mineral soil, and iv) no disturbance (control). R_s measurements were acquired with a portable respiration system during two growing seasons. To assess the treatments’ effects on litter decomposition rates, needles or coarse roots (Ø = 6 mm) were incubated in litterbags at positions they would be located after the treatments (buried, or on top of the soil). The results indicate that site preparation-simulating treatments have no effect or may significantly reduce, rather than increase, CO₂ emissions during the following two years. They also show that buried litter decomposes more rapidly than litter on the surface, but in other respects the treatments have little effect on litter decomposition rates.

• Mjöfors, Swedish University of Agricultural Sciences (SLU), Department of Soil and Environment, P.O. Box 7014, 150 07 Uppsala, Sweden E-mail: kristina.mjofors@slu.se
• Strömgren, Swedish University of Agricultural Sciences (SLU), Department of Soil and Environment, P.O. Box 7014, 150 07 Uppsala, Sweden E-mail: Monika.stromgren@slu.se
• Nohrstedt, Swedish University of Agricultural Sciences (SLU), Department of Soil and Environment, P.O. Box 7014, 150 07 Uppsala, Sweden E-mail: Hans-orjan.nohrstedt@slu.se
• Gärdenäs, Swedish University of Agricultural Sciences (SLU), Department of Soil and Environment, P.O. Box 7014, 150 07 Uppsala, Sweden E-mail: Annemieke.gardenas@slu.se

The density of Picea abies [L.] Karst. regeneration on different microsites, the quantity and quality of woody microsites, and seedling occurrence probability on stumps and fallen deadwood were studied in a subalpine forest that has been under protection for approximately 30–40 years (Gorce Mountains in the western Carpathians). Thirty percent of seedlings and 29% of saplings grew on stumps and fallen deadwood, while the remaining regeneration occurred on soil surface and mounds created by uprooted trees. The occurrence probability of Picea seedlings on fallen deadwood increased with deadwood diameter and decay stage and with the volume of living trees, and decreased with increased density of living trees, sapling density, and land slope. Furthermore, seedlings were more likely to grow on stumps with a greater diameter and in plots with higher sapling density, but less likely to grow on higher stumps. Stumps and fallen deadwood covered about 4% of the forest floor, but the material that is most important for promoting regeneration (strongly decomposed logs and those of a diameter exceeding 30 cm) took up only about 22 m² ha^-1. We have concluded that in a subalpine forest that has been protected for 30–40 years regeneration processes take place mostly on soil surface and stumps. The role of fallen deadwood increases over time as a greater number of suitable logs (in terms of size and decay stage) become available.

• Bujoczek, University of Agriculture in Krakow, E-mail: lbujoczek@gmail.com
• Bujoczek, University of Agriculture in Krakow, E-mail: bujoczek.m@gmail.com
• Banaś, University of Agriculture in Krakow, E-mail: rlbanas@cyf-kr.edu.pl
• Zięba, University of Agriculture in Krakow, E-mail: rlzieba@cyf-kr.edu.pl

• Kreutz, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: andreas.kreutz@wald-rpl.de
• Aakala, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland http://orcid.org/0000-0003-0160-6410 E-mail: tuomas.aakala@helsinki.fi
• Grenfell, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: russell.grenfell@gmail.com
• Kuuluvainen, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: timo.kuuluvainen@helsinki.fi

• Chen, Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China E-mail: chenxiao_0123@126.com
• Page-Dumroese, U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, 1221 South Main Street, Moscow, ID 83843, USA E-mail: ddumroese@fs.fed.us
• Lv, College of Plant Science and Technology, Tarim University, Alar Xinjiang, 843300, China E-mail: lvrh514723@126.com
• Wang, Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China E-mail: fuyuerdejia@126.com
• Li, Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China E-mail: glli226@163.com
• Liu, Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083, China E-mail: lyong@bjfu.edu.cn

• Pearson, Finnish Forest Research Institute, Western Finland Regional Unit, Kaironiementie 15, FI-39700 Parkano, Finland E-mail: meeri.pearson@metla.fi
• Saarinen, Finnish Forest Research Institute, Western Finland Regional Unit, Kaironiementie 15, FI-39700 Parkano, Finland E-mail: ms@nn.fi
• Minkkinen, University of Helsinki, Department of Forest Sciences, Helsinki, Finland E-mail: km@nn.fi
• Silvan, Finnish Forest Research Institute, Western Finland Regional Unit, Kaironiementie 15, FI-39700 Parkano, Finland E-mail: ns@nn.fi
• Laine, Finnish Forest Research Institute, Western Finland Regional Unit, Kaironiementie 15, FI-39700 Parkano, Finland E-mail: jl@nn.fi

• Yang, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China & College of Life Sciences, Chongqing Normal University, Chongqing, 400047, China E-mail: yy@nn.cn
• Yao, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China E-mail: yaoya@ms.xjb.ac.cn
• Zhang, Institute for Plant Protection and Soil sciences, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China E-mail: xz@nn.cn

• Miettinen, Finnish Game and Fisheries Research Institute, Finland E-mail: janne.miettinen@rktl.fi
• Helle, Finnish Game and Fisheries Research Institute, Finland E-mail: ph@nn.fi
• Nikula, Finnish Forest Research Institute, Finland E-mail: an@nn.fi
• Niemelä, University of Turku, Dept of Biology E-mail: pn@nn.fi

• Nagaike, Yamanashi Forest Research Institute, Masuho, Yamanashi 400-0502, Japan E-mail: nagaike-zty@pref.yamanashi.lg.jp

• Miettinen, Kankurinhaka 14, FI-90450 Kempele, Finland E-mail: janne.miettinen@rktl.fi
• Helle, Finnish Game and Fisheries Research Institute, Tutkijantie 2 E, FI-90570 Oulu, Finland E-mail: ph@nn.fi
• Nikula, Finnish Forest Research Institute, Rovaniemi Research Unit, Eteläranta 55, FI-99600 Rovaniemi, Finland E-mail: an@nn.fi
• Niemelä, University of Turku, Department of Biology, FI-20014 University of Turku, Finland E-mail: pn@nn.fi

• Vidal, Inventaire Forestier National, Château des Barres, Nogent-sur-Vernisson, France E-mail: claude.vidal@ifn.fr
• Lanz, WSL/FNP, Abteilung Landschaftsinventuren, Birmensdorf, Switzerland E-mail: al@nn.ch
• Tomppo, Finnish Forest Research Institute, Vantaa Research Unit, Vantaa, Finland E-mail: et@nn.fi
• Schadauer, Bundesamt und Forschungszentrum für Wald, Wien, Austria E-mail: ks@nn.at
• Gschwantner, Bundesamt und Forschungszentrum für Wald, Wien, Austria E-mail: tg@nn.at
• di Cosmo, ISAFA, Villazzano, Italy E-mail: ldc@nn.it
• Robert, Inventaire Forestier National, Ch‰teau des Barres, Nogent-sur-Vernisson, France E-mail: nr@nn.fr

• Püttsepp, Department of Ecology, Swedish University of Agricultural Sciences, P.O. Box 7072, SE-75007 Uppsala, Sweden; Estonian University of Life Sciences, Kreuzwaldi 64, Tartu 51014, Estonia E-mail: ulle.puttsepp@ekol.slu.se
• Lõhmus, Institute of Geography, University of Tartu, Vanemuise 46, Tartu 51014, Estonia E-mail: kl@nn.ee
• Koppel, Estonian University of Life Sciences, Kreuzwaldi 64, Tartu 51014, Estonia E-mail: ak@nn.ee

• Veijalainen, Finnish Forest Research Institute, FI-77600 Suonenjoki, Finland E-mail: amv@nn.fi
• Juntunen, Finnish Forest Research Institute, FI-77600 Suonenjoki, Finland E-mail: mlj@nn.fi
• Lilja, Finnish Forest Research Institute, PO Box 18, FI-01301 Vantaa, Finland E-mail: al@nn.fi
• Heinonen-Tanski, Univ. of Kuopio, Dept. of Environm. Sc., PO Box 1627, FI-70211 Kuopio, Finland E-mail: hht@nn.fi
• Tervo, Finnish Forest Research Institute, FI-77600 Suonenjoki, Finland E-mail: lt@nn.fi

• Li, Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu 610041, P. R. China E-mail: licy@cib.ac.cn
• Zhang, Chengdu Institute of Biology, Chinese Academy of Sciences, P.O. Box 416, Chengdu 610041, P. R. China; Graduate School of the Chinese Academy of Sciences, Beijing 100039, P.R. China E-mail: xz@nn.cn
• Liu, Sichuan Academy of Forestry, Chengdu 610081, P. R. China E-mail: xl@nn.cn
• Luukkanen, Viikki Tropical Resources Institute, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: ol@nn.fi
• Berninger, Département des sciences biologiques, Cp 8888 succ centre ville, Université du Québec à Montréal, Montréal (QC) H3C 3P8, Canada E-mail: fb@nn.ca

• Levula, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: janne.levula@helsinki.fi
• Ilvesniemi, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: hi@nn.fi
• Westman, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: cjw@nn.fi

• Légaré, Université du Québec en Abitibi-Témiscamingue, Groupe de recherche en écologie forestière interuniversitaire, 445, boulevard de l'Université, Rouyn-Noranda, QC, Canada J9X 5E4 E-mail: sonia.legare@uqat.uquebec.ca
• Bergeron, NSERC-UQAT-UQAM, Industrial Chair in sustainable forest management, CP 8888, succ. Centre-Ville, Montréal, QC, Canada H3C 3P8 E-mail: yb@nn.ca
• Paré, Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, P.O. Box 3800, Sainte-Foy, QC, Canada G1V 4C7 E-mail: dp@nn.ca

• Haeussler, C2 Site 81 RR#2 Monckton Rd., Smithers, B.C., Canada V0J 2N0 E-mail: skeena@bulkley.net
• Bedford, B.C. Ministry of Forests, P.O. Box 9513 Stn. Prov. Govt., Victoria, B.C., Canada, V8W 9C2 E-mail: lb@nn.ca
• Leduc, Groupe de recherche en écologie forestière interuniversitaire, Université du Québec à Montréal, CP 8888, Succursale A, Montréal, Québec, Canada, H3C 3P8 E-mail: al@nn.ca
• Bergeron, Groupe de recherche en écologie forestière interuniversitaire, Université du Québec à Montréal, CP 8888, Succursale A, Montréal, Québec, Canada, H3C 3P8 E-mail: yb@nn.ca
• Kranabetter, B.C. Ministry of Forests, Bag 5000, Smithers, B.C., Canada, V0J 2N0 E-mail: jmk@nn.ca

• Liu, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: cliu@silvia.helsinki.fi
• Westman, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: cjw@nn.fi
• Ilvesniemi, Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: hi@nn.fi

• Mäkipää, The Finnish Forest Research Institute, Vantaa, Finland E-mail: raisa.makipaa@metla.fi
• Linkosalo, The Finnish Forest Research Institute, Vantaa, Finland E-mail: ts@nn.fi