Articles containing the keyword 'OLS'

The carbon reservoir of ecosystems was estimated based on field measurements for forests and peatlands on an area in Finland covering 263,000 km² and extending about 900 km across the boreal zone from south to north. More than two thirds of the reservoir was in peat, and less than ten per cent in trees. Forest ecosystems growing on mineral soils covering 144,000 km² contained 10–11 kg C m^-2 on an average, including both vegetation (3.4 kg C m^-2) and soil (uppermost 75 cm; 7.2 kg C m^-2). Mire ecosystems covering 65,000 km² contained an average of 72 kg C m^-2 as peat. For the landscape consisting of peatlands, closed and open forests, and inland water, excluding arable and built-up land, a reservoir of 24.6 kg C m^-2 was observed. This includes the peat, forest soil and tree biomass. This is an underestimate of the true total reservoir, because there are additional unknown reservoirs in deep soil, lake sediments, woody debris, and ground vegetation. Geographic distributions of the reservoirs were described, analysed and discussed. The highest reservoir, 35–40 kg C m^-2, was observed in sub-regions in central western and north western Finland. Many estimates given for the boreal carbon reservoirs have been higher than those of ours. Either the Finnish environment contains less carbon per unit area than the rest of the boreal zone, or the global boreal reservoir has earlier been overestimated. In order to reduce uncertainties of the global estimates, statistically representative measurements are needed especially on Russian and Canadian peatlands.

• Kauppi, E-mail: pk@mm.unknown
• Hänninen, E-mail: ph@mm.unknown
• Henttonen, E-mail: hh@mm.unknown
• Ihalainen, E-mail: ai@mm.unknown
• Lappalainen, E-mail: el@mm.unknown
• Posch, E-mail: mp@mm.unknown
• Starr, E-mail: ms@mm.unknown
• Tamminen, E-mail: pt@mm.unknown

The Värriö environmental measurement station has been designed and constructed during 1991 and 1992. The measurement system consists of measurement units for gases (sulphur dioxide, ozone, carbon dioxide), particles, photosynthesis and irradiation. A meteorological station is also included. The preliminary measurement period was started on August, 1991. During the first year (1991–1992) some parts of the system were redeveloped and rebuilt. Full, continuous measurement started in August 1992. The system has been working quite reliably, with good accuracy. The preliminary results show that pollution episodes are observed when the wind direction is from Monchegorsk or Nikel, the main emission sources in Kola Peninsula.

• Hari, E-mail: ph@mm.unknown
• Aalto, E-mail: pa@mm.unknown
• Hämeri, E-mail: kh@mm.unknown
• Kulmala, E-mail: mk@mm.unknown
• Lahti, E-mail: tl@mm.unknown
• Luoma, E-mail: sl@mm.unknown
• Palva, E-mail: lp@mm.unknown
• Pohja, E-mail: tp@mm.unknown
• Pulliainen, E-mail: ep@mm.unknown
• Siivola, E-mail: es@mm.unknown
• Vesala, E-mail: tv@mm.unknown

In soil profiles from a series of uplands of different site types bulk density, density of solids and porosity of soil were clearly related to soil organic matter content and its distribution in the soil profile. Soil organic matter contents were also strongly correlated to effective cation exchange capacity (CEC) and soil acidity. Site fertility was primarily related to the fine fraction (ø<0.06 mm) content in the C horizon and related properties (i.e. CEC). In the humus layer, the content of exchangeable bases and base saturation most strongly related to site fertility.

The PDF includes an abstract in English.

• Westman, E-mail: cw@mm.unknown

The paper deals with the development of hand tools and their maintenance methods, and the improvement of working techniques in Finland in the era when forest work was mostly done by muscular power. The development was carried out in a close connection with professional training, permitting the results to be distributed widely throughout the country at short duration courses, and simultaneously collecting new information.

The phases of the entire development cycle is described from founding of the development and training organization to standardization of the tools and comparisons to similar foreign and Finnish tools. On the basis of this, along with analyses and synthesis performed, new hand-made prototypes were created and then tested on forest work sites. The knowledge was used to produce test series in a tool factory, and feedback was gathered from skilled workers. On experience gained, best tools selected could be put into manufacturing. This work gave a natural basis to investigate even working techniques. Good results were achieved through cooperation between researchers, users, manufacturing industry and trade, as well as vocational training.

The PDF includes a summary in Finnish.

• Kantola, E-mail: mk@mm.unknown

The aim of the study was to compare the newly introduced brush cutter to ordinary hand tools in clearing of cutting areas and thinning young birch (Betula sp.) and Scots pine (Pinus Sylvestris L.) stands. Working with a prototype of the brush cutter, Brushmaster, reduced the total working time by 15-20% compared to bush knife and axe, in spite of the cutter’s weight. At rainy weather the advantage of Brushmaster dissapeared because of clogging of the cutter’s air filter. The prototype proved to be more effective when clearing a cutting area, and hand tools seemed to be faster if damage to the remaining trees have to be avoided.

In addition, eight either lighter or more effective motor saws or brush cutters were compared mutually, and the effect of motor effect, weight, handiness, arrangement of suspenders and handles is discussed. With these improved types of the cutter it was possible to shorten the total working time in thinning of stands (mostly clearing of young stands) to 30-40% of the total working time compared to hand tools. The most modern saws appeared to be best adapted in clearing cutting areas.

The article includes an abstract in English.

• Sirén, E-mail: gs@mm.unknown

Forestry has developed at an extremely rapid pace in the United States during the past eight years. This has created job opportunities for foresters educated in the schools of forestry. From 1946 to 1953 American schools of forestry graduated 9,719 foresters.

The schools of forestry are gradually being emancipated from the control by colleges of agriculture and mechanical art. Professional demands are growing at a rapid pace, and the schools are expanding their programs to meet these changes. Faculties have responded to these new needs by adding new courses and curriculums. Colleges can perform their task best through improving the faculty and organizing courses in which the student becomes an active learner rather than a passive recipient of information.

The Silva Fennica issue 61 was published in honour of professor Eino Saari‘s 60th birthday.

• Shirley, E-mail: hs@mm.unknown

The tree stem volume models of Norway spruce, Scots pine and silver and downy birch currently used in Finland are based on data collected during 1968–1972. These models include four different formulations of a volume model, with three different combinations of independent variables: 1) diameter at height of 1.3 m above ground (dbh), 2) dbh and tree height (h) and 3) dbh, h and upper diameter at height of 6 m (d6). In recent National Forest Inventories of Finland, a difference in the mean volume prediction between the models with and without the upper diameter as predictor has been observed. To analyze the causes of this difference, terrestrial laser scanning (TLS) was used to acquire a large dataset in Finland during 2017–2018. Field-measured predictors and volumes predicted using spline functions fitted to the TLS data were used to re-calibrate the current volume models. The trunk form is different in these two datasets. The form height is larger in the new data for all diameter classes, which indicates that the tree trunks are more slender than they used to be. One probable reason for this change is the increase in stand densities, which is at least partly due to changed forest management. In models with both dbh and h as predictors, the volume is smaller a given h class in the data new data than in the old data, and vice versa for the diameter classes. The differences between the old and new models were largest with pine and smallest with birch.

• Kangas, Natural Resources Institute Finland (Luke), Yliopistokatu 6 B, FI-80100 Joensuu, Finland https://orcid.org/0000-0002-8637-5668 E-mail: annika.kangas@luke.fi
• Henttonen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: helena.henttonen@luke.fi
• Pitkänen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0001-5389-8713 E-mail: timo.p.pitkanen@luke.fi
• Sarkkola, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: sakari.sarkkola@luke.fi
• Heikkinen, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland https://orcid.org/0000-0003-3527-774X E-mail: juha.heikkinen@luke.fi

Environmental planning for of the maintenance of different conservation objectives should take into account multiple contrasting criteria based on alternative uses of the landscape. We develop new concepts and approaches to describe and measure conflicts among conservation objectives and for resolving them via multiobjective optimization. To measure conflicts we introduce a compatibility index that quantifies how much targeting a certain conservation objective affects the capacity of the landscape for providing another objective. To resolve such conflicts we find compromise solutions defined in terms of minimax regret, i.e. minimizing the maximum percentage of deterioration among conservation objectives. Finally, we apply our approach for a case study of management for biodiversity conservation and development in a forest landscape. We study conflicts between six different forest species, and we identify management solutions for simultaneously maintaining multiple species’ habitat while obtaining timber harvest revenues. We employ the method for resolving conflicts at a large landscape level across a long 50-years forest planning horizon. Our multiobjective approach can be an instrument for guiding hard choices in the conservation-development nexus with a perspective of developing decision support tools for land use planning. In our case study multiple use management and careful landscape level planning using our approach can reduce conflicts among biodiversity objectives and offer room for synergies in forest ecosystems.

• Mazziotta, University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland; Center for Macroecology Evolution and Climate, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark; Stockholm Resilience Centre, Stockholm University, Kräftriket 2b, 11429 Stockholm, Sweden http://orcid.org/0000-0003-2088-3798 E-mail: a_mazziotta@hotmail.com
• Podkopaev, University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland; Systems Research Institute, Polish Academy of Sciences, Newelska 6, 01-447 Warsaw, Poland E-mail: dmitry.podkopaev@ibspan.waw.pl
• Triviño, University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland E-mail: maria.trivino@jyu.fi
• Miettinen, University of Jyväskylä, Faculty of Information Technology, P.O. Box 35, FI-40014 University of Jyväskylä, Finland E-mail: kaisa.miettinen@jyu.fi
• Pohjanmies, University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland E-mail: tahti.t.pohjanmies@jyu.fi
• Mönkkönen, University of Jyväskylä, Department of Biological and Environmental Science, P.O. Box 35, FI-40014 University of Jyväskylä, Finland E-mail: mikko.monkkonen@jyu.fi

• Cienciala, Institute of Forest Ecosystem Research (IFER), Areal 1. Jilovske a.s. 1544, 254 01 Jilove u Prahy, Czech Republic E-mail: emil.cienciala@ifer.cz
• Tomppo, Metla, Finnish Forest Research Institute, Finland E-mail: et@nn.fi
• Snorrason, Icelandic Forest Research, Iceland E-mail: as@nn.is
• Broadmeadow, Forestry Commission, Forest Research Alice Holt Logdge, United Kingdom E-mail: mb@nn.uk
• Colin, French National Forest Inventory, France E-mail: ac@nn.fr
• Dunger, Federal Research Centre for Forestry and Forest Products, Institute of Forest Ecology and Forest Assessment, Germany E-mail: kd@nn.de
• Exnerova, Institute of Forest Ecosystem Research, Czech Republic E-mail: ze@nn.cz
• Lasserre, Department of Environment and Territory Sciences and Technologies, University of Molise, Italy E-mail: bl@nn.it
• Petersson, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Sweden E-mail: hp@nn.se
• Priwitzer, National Forest Centre, Forest Research Institute. Slovak Republic E-mail: tb@nn.sk
• Sanchez, Forest Health Unit, General Directorate for Biodiversity, Environmental Ministry, Spain E-mail: gs@nn.es
• Ståhl, Swedish University of Agricultural Sciences, Department of Forest Resource Management, Sweden E-mail: gs@nn.se

• Dzierzon, Institut für Forstliche Biometrie und Informatik, Universität Göttingen, Büsgenweg 4, D-37077 Göttingen, Germany E-mail: hdzierz@gwdg.de
• Sievänen, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: rs@nn.fi
• Kurth, Institut für Informatik, Brandenburgische Technische Universität Cottbus, P.O. Box 101344, D-03013 Cottbus, Germany E-mail: wk@nn.de
• Perttunen, The Finnish Forest Research Institute, Vantaa Research Centre, P.O. Box 18, FIN-01301 Vantaa, Finland E-mail: jp@nn.fi
• Sloboda, Institut für Forstliche Biometrie und Informatik, Universität Göttingen, Büsgenweg 4, D-37077 Göttingen, Germany E-mail: bs@nn.de

• Villasante, Agroforestry Departament, Universitat de Lleida, Av. Rovira Roure 177, 25198 Lleida, Spain http://orcid.org/0000-0002-7549-7424 E-mail: avillasante@eagrof.udl.cat
• Fernandez, Agroforestry Departament, Universitat de Lleida, Av. Rovira Roure 177, 25198 Lleida, Spain E-mail: cfernandez@eagrof.udl.cat