Finnish Forest Research Institute

www.metla.fi/index.html
Parkano, Finland

The Finnish Forest Research Institute , known as Metla, is a subordinate agency to the Ministry of Agriculture and Forestry of the Government of Finland. It has statutory duties to promote, through research, the economical, ecological, and socially sustainable management and use of forests. Metla is one of Europe's largest forestry research institutes, with an annual budget of around €40 million and 9 main research units. Wikipedia.

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Wallenius T.,Finnish Forest Research Institute
Silva Fennica | Year: 2011

Steep decline in forest fires about a century ago occurred in coniferous forests over large areas in North America and Fennoscandia. This poorly understood phenomenon has been explained by different factors in different regions. The objective of this study is to evaluate the validity of the four most commonly suggested causes of the decrease in forest fires: fire fighting, over-grazing, climate change and human influence. I compiled the available dendrochronological data and estimated the annually burned proportions of Pinus-dominated forests in four subcontinental regions during the past 500 years. These data were compared to the development of fire suppression, grazing pressure, climate and human livelihoods. The annually burned proportions declined over 90% in all studied regions. In three out of the four regions fires decreased decades before fire suppression began. Available drought data are annually well correlated with fires but could not explain the decrease of the level in annually burned areas. A rapid increase in the number of livestock occurred at the same time with the decrease in fires in the Western US but not in Fennoscandia. Hence, fire suppression in Central Fennoscandia and over-grazing in the Western US may have locally contributed to the reduction of burned areas. More general explanation is offered by human influence hypothesis: the majority of the past forest fires were probably caused by humans and the decrease in the annually burned areas was because of a decrease in human caused fires. This is in accordance with the old written records and forest fire statistics. The decrease in annually burned areas, both in Fennoscandia and the United States coincides with an economic and cultural transition from traditional livelihoods that are associated with high fire use to modern agriculture and forestry.


The objective of the study was to ascertain the relationship of thinning intensity of downy birch (Betula pubescens Ehrh.) stands with height, crown, and diameter development as well as pulpwood, stem volume, and biomass increment using long-term (20-30 years) field experiments. Diameter growth of birches increased with thinning intensity during the first 15 years from thinning in all development phases, though after that it did so only for the youngest stands. The thinning response was low. Thinning intensity had no influence on increase in height. In terms of stem volume with bark, the mortality in unthinned stands during the study period was 30-45 m3 ha-1. The mean stem number in unthinned birch thickets fell from 25 000 ha-1 at a dominant height of 7 m to 3000 ha-1 at 18 m. The stem volume increment over the first 15 years was highest (5-6 m3 ha-1 a-1) on the very lightly thinned or unthinned plots, but later there was no significant difference between initial thinning intensities. The maximum above-ground leafless biomass (over 100 Mg ha-1) was achieved on very lightly thinned plots. Also, the total production (including thinning removal) of biomass or stem volume or even the production of pulpwood increased with stand density, with these values being greatest for very lightly thinned or unthinned plots. During 50-year rotation, the highest leafless above-ground biomass production was 2.5 Mg ha-1 a-1 as a mean value from the experiments. The highest mean annual production of pulpwood (d > 6.5 cm) was 3.2 m3 ha-1a-1, and, in practice, no saw timber or veneer timber was produced, because of the small size and low quality of the stems. A thinning in downy birch stands increased slightly the size of stems to be removed in future cuttings, but with exception for very light thinning it decreased the production of biomass and merchantable wood.


Ruotsalainen S.,Finnish Forest Research Institute
Scandinavian Journal of Forest Research | Year: 2014

Forest tree breeding started in the middle of the twentieth century and since then the use of improved forest regeneration material has become an essential part of forestry in many countries. This review describes methods and achievements of tree breeding programmes, which aim at increasing the quantities and improving qualities of wood-based raw materials through selection, field testing and controlled crossings. Most improved materials currently deployed are seed crops from first-generation phenotypic or tested seed orchards, which offer 10-25% gains in yield depending on the selection intensity of parent trees. Methods of vegetative propagation are developed intensively so that it could be applied to a larger range of species, because it offers high genetic gain and uniformity of the material. Genomic tools are also developed to enhance the efficacy of selection. Applications of genetic engineering are currently limited to research purposes. Forest tree breeding will be an integral part of bioeconomy in securing the production of good quality raw materials in large quantities and will have a significant economic impact on the profitability of forestry in the long term. © 2014 © 2014 Taylor & Francis.


Wall A.,Finnish Forest Research Institute
Forest Ecology and Management | Year: 2012

The increased removal of biomass from the forest sites with whole-tree harvesting has raised concern over the sustainability of site productivity. In this study, the results from eighty-six studies that quantify the short-term effects of whole-tree harvesting as compared with stem-only harvesting on soil- and tree-based indicators of site productivity were reviewed with the aim of estimating the risks of both negative and positive impacts on site productivity. The risk was defined as the combination of the probability of occurrence of an impact in an indicator of site productivity and the magnitude of the impact. According to risk analysis of this study, soil pH, P, K, Ca, Mg and tree diameter were priority indicators of site productivity on which to act to mitigate risks of site productivity decline following whole-tree harvesting. Following clear-cutting, the probability of occurrence of a negative effect of whole-tree harvesting on these indicators of site productivity was 31-39% and the mean decrease 13-60%. The results showed that the risk level of change in indicators of site productivity following clear-cutting with whole-tree harvesting might be high enough to justify a need for mitigation measures. Following thinning with whole-tree harvesting, the probability of occurrence of the negative effects and the risk levels were lower in comparison to clear-cutting. Therefore, mitigation measures at thinning may not be needed. © 2012 Elsevier B.V.


Larjavaara M.,Finnish Forest Research Institute | Muller-Landau H.C.,Smithsonian Tropical Research Institute
Methods in Ecology and Evolution | Year: 2013

Tree height is a key variable for estimating tree biomass and investigating tree life history, but it is difficult to measure in forests with tall, dense canopies and wide crowns. The traditional method, which we refer to as the 'tangent method', involves measuring horizontal distance to the tree and angles from horizontal to the top and base of the tree, while standing at a distance of perhaps one tree height or greater. Laser rangefinders enable an alternative method, which we refer to as the 'sine method'; it involves measuring the distances to the top and base of the tree, and the angles from horizontal to these, and can be carried out from under the tree or from some distance away. We quantified systematic and random errors of these two methods as applied by five technicians to a size-stratified sample of 74 trees between 5.7 and 39.2 m tall in a Neotropical moist forest in Panama. We measured actual heights using towers adjacent to these trees. The tangent method produced unbiased height estimates, but random error was high, and in 6 of the 370 measurements, heights were overestimated by more than 100%. The sine method was faster to learn, displayed less variation in heights among technicians, and had lower random error, but resulted in systematic underestimation by 20% on average. We recommend the sine method for most applications in tropical forests. However, its underestimation, which is likely to vary with forest and instrument type, must be corrected if actual heights are needed. © 2013 British Ecological Society.


Saksa T.,Finnish Forest Research Institute
Forest Ecology and Management | Year: 2013

In southern Finland, large-scale stump harvesting from regeneration areas began in the early 2000s. At that time, stump harvesting and additional soil scarification for planting was performed simultaneously. The aim of this study was to investigate the regeneration result, particularly the outcome of the natural regeneration of birch after stump harvesting, compared to the result achieved on a conventionally soil prepared area without stump lifting. The study material consisted of 37 stump-harvested areas 4-9. years old, and 10 conventionally soil prepared regeneration areas of a corresponding age. In the case of Norway spruce planting, the result did not differ between stump-harvested and conventionally soil prepared areas, but the share of pure coniferous stands after pre-commercial thinning was estimated to be 30% after stump harvesting and 50% in conventional regeneration areas. In stump-harvested areas, the share of disturbed soil surface seemed remarkably higher and the time for seedling emergence longer than in conventionally soil prepared areas without stump lifting. The number of Scots pine seedlings was somewhat higher after stump harvesting than after conventional soil preparation, but there was great variation between regeneration areas. As for Norway spruce, there were fewer natural seedlings on stump-harvested areas. The number of birch seedlings was somewhat higher after stump lifting, but there was huge variation between regeneration areas. Most birch-rich regeneration areas were discovered after the stump harvest; the maximum mean density was over 60,000 birch seedlings ha-1. Birch regeneration was most abundant on fine textured, moist mineral soils or peat layered spots. The mean temperature in May and June during the first summer, and rainfall in May and June during the second summer after the stump harvest, correlated positively with the abundance of birch seedlings. © 2012 Elsevier B.V.


Tahvanainen T.,Finnish Forest Research Institute | Anttila P.,Finnish Forest Research Institute
Biomass and Bioenergy | Year: 2011

The increasing use of bioenergy has resulted in a growing demand for long-distance transportation of energy wood. For both biofuels and traditional forest products, the importance of energy efficiency and rail use is growing. A GIS-based model for energy wood supply chains was created and used to simulate the costs for several supply chains in a study area in eastern Finland. Cost curves of ten supply chains for logging residues and full trees based on roadside, terminal and end-facility chipping were analyzed. The average procurement costs from forest to roadside storage were included. Railway transportation was compared to the most commonly used truck transportation options in long-distance transport. The potential for the development of supply chains was analyzed using a sensitivity analysis of 11 modified supply chain scenarios.For distances shorter than 60 km, truck transportation of loose residues and end-facility comminution was the most cost-competitive chain. Over longer distances, roadside chipping with chip truck transportation was the most cost-efficient option. When the transportation distance went from 135 to 165 km, depending on the fuel source, train-based transportation offered the lowest costs. The most cost-competitive alternative for long-distance transport included a combination of roadside chipping, truck transportation to the terminal and train transportation to the plant. Due to the low payload, the energy wood bundle chain with train transportation was not cost-competitive. Reduction of maximum truck weight increased the relative competitiveness of loose residue chains and train-based transportation, while reduction of fuel moisture increased competitiveness, especially of chip trucks. © 2010 Elsevier Ltd.


Heiskanen J.,Finnish Forest Research Institute
New Forests | Year: 2013

Sphagnum peat has been the most commonly used growing medium in containers in tree nurseries worldwide for its good growing properties. As a result of increasing costs and environmental incentives, seedling-growers are seeking more local growing medium components such as composts. Composts are, however, diverse products with varying chemical, physical, and hygienic properties and therefore require thorough testing before real-world use. In this study, a commonly used compost (raw materials: sewage sludge, biowaste, peat, wood chips) was tested for feasibility as a component (0-30 vol.%) of a sphagnum peat container medium for growing Norway spruce (Picea abies (L.) Karst.) container seedlings in a forest-tree nursery. In proportions of up to 30% in peat, the compost additive used was shown to be a feasible material for seedling growing in forest nurseries. On average, the seedlings grew best in pure peat, but the compost additions to peat showed no marked reduction in seedling growth in greenhouses, nor were there any effect on seedling growth in the first summer after outplanting. However, a slightly elevated risk of seed non-germination and of seedling mortality was observed when the growing media contained compost in proportions of 20% or more. The compost additive in peat also changed the bulk density, structure, and chemical properties of the medium during nursery growing. The results suggest that seedling watering and fertilisation should be adjusted for each growing medium mix separately to achieve correct water, oxygen, and nutrient availability in containers during nursery growing. © 2011 Springer Science+Business Media B.V.


Asikainen A.,Finnish Forest Research Institute
Scandinavian Journal of Forest Research | Year: 2010

The use of stumps for energy production has grown rapidly in Finland and is also commencing in Sweden, the UK and a number of other countries. Practically all stumps are comminuted either at the plant or at terminals, whereas a major part of small-diameter trees and logging residues is chipped at roadside landing. Until now, crushing of stumps has been done with heavy, often stationary, crushers. In smaller plants, construction of a stationary crusher is not economically feasible. In addition, transportation of stumps calls for special trucks, while economical transport distances are short owing to the small payload. Recently, effective mobile crushers suitable for the comminution of stumps, that can also operate as mobile chippers for logging residue and small-diameter trees, have been introduced. They move from landing to landing with the crushed material transported to the end-user by trucks. In this study a discrete-event simulation model was programmed to find optimal set-ups for the supply chain of crushed material made from stumps at different road transport distances. The simulation model was based on the continuous supply of crushed material from landings to a district heating plant. Transportation distances varied from 20 to 120 km, while the number of trucks varied from one to four. It was found that already at 20 km the use of two chip trucks is competitive and after 40 km a third truck should be introduced into the system. Beyond 100 km four trucks would be needed. The results were compared with those obtained from a static spreadsheet model. The static model underestimated the waiting cost in the situation where the productivity of crushing and truck transport was almost balanced. © 2010 Taylor & Francis.


Classic studies have successfully linked single-species abundances, life-history traits, assemblage structures and biomass of carabid beetles to past and present, human-caused environmental impacts and variation in 'natural' conditions. This evidence has led many to suggest carabids to function as 'indicators' - a term that bears multiple meanings. Here, a conservation-oriented definition for an indicator is used, carabid indicator potential from seven views is evaluated, and ways to proceed in indicator research are discussed. (1) Carabid species richness poorly indicates the richness and abundance of other taxa, which underlines the importance of using multiple taxa in environmental assessments. The ability of assemblage indices and specialist or functional-group abundances to reflect rare species and habitats should be examined in detail. (2) Experimental evidence suggests that carabids may potentially serve as keystone indicators. (3) Carabids are sensitive to human-altered abiotic conditions, such as pesticide use in agro-ecosystems and heavy metal contamination of soils. Carabids might thus reflect ecological sustainability and 'ecosystem health'. (4) Carabid assemblages host abundant species characteristic of particular habitat types or successional stages, which makes them promising dominance indicators. (5) Carabids reflect variation in 'natural' conditions, but vegetation and structural features are more commonly adopted as condition indicators. Carabids nevertheless provide yet another, equally accurate, view on the structure of the environment. (6) Carabids may function as early-warning signalers, as suggested by recent studies linking climate and carabid distributions. (7) Carabids reflect natural and human-caused disturbances and management, but the usefulness of these responses for conservation purposes requires further research. In summary, European carabids appear useful model organisms and possibly indicators because they are diverse, taxonomically and ecologically well-known, efficiently reflect biotic and abiotic conditions, are relevant at multiple spatial scales, and are easy to collect in sufficiently large numbers to allow statistical analyses. The assumption that carabid responses would reflect rare environmental conditions or the responses of rare and threatened species - crucial information for conservationists and managers - has not yet been critically evaluated. Even if it holds, the usefulness will be context dependent: species and their populations vary, conditions vary, questions put forward vary, and assessment goals vary. © M.J. Koivula.

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