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Suomi kohkaa bioenergiasta, mutta sivuuttaa parhaat mahdollisuutensa. Käsitykset energiatuotannon tehokkuudesta ja ympäristöystävällisyydestä ovat huteralla pohjalla.

Amid widespread reports of deforestation, some nations have nevertheless experienced transitions from deforestation to reforestation. In a causal relationship, the Forest Identity relates the carbon sequestered in forests to the changing variables of national or regional forest area, growing stock density per area, biomass per growing stock volume, and carbon concentration in the biomass. It quantifies the sources of change of a nation's forests. The Identity also logically relates the quantitative impact on forest expanse of shifting timber harvest to regions and plantations where density grows faster. Among 50 nations with extensive forests reported in the Food and Agriculture Organization's comprehensive Global Forest Resources Assessment 2005, no nation where annual per capita gross domestic product exceeded $4,600 had a negative rate of growing stock change. Using the Forest Identity and national data from the Assessment report, a single synoptic chart arrays the 50 nations with coordinates of the rates of change of basic variables, reveals both clusters of nations and outliers, and suggests trends in returning forests and their attributes. The Forest Identity also could serve as a tool for setting forest goals and illuminating how national policies accelerate or retard the forest transitions that are diffusing among nations. Academy of Finland [Grants 1109942 and 1205668 (to P.E.K.)] National Natural Science Foundation of China [Grant 40021101 (to J.F.)]

Among wealthy countries, increasing imports of natural resources to allow for unchecked consumption and greater domestic environmental conservation has become commonplace. This practice can negatively affect biodiversity conservation planning if natural resource harvest is merely pushed across political borders. As an example, we focus on the boreal forest ecosystem of Finland and northwest Russia. While the majority of protected forests are in northern Finland, the majority of biodiversity is in southern Finland, where protection is more difficult due to high private ownership, and the effectiveness of functioning conservation networks is more uncertain due to a longer history of land use. In northwest Russia, the current protected areas are inadequate to preserve most of the region’s naturally dynamic and old growth forests. Increased importation of wood from northwest Russia to Finland may jeopardize the long-term viability of species in high diversity conservation areas in both Russia and Finland, through isolating conservation areas and lowering the age of the surrounding forest mosaic. The boreal forest ecosystem of Fennoscandia and northwest Russia would thus be best conserved by a large scale, coordinated conservation strategy that addresses long-term conservation goals and wood consumption, forest industries, logging practices and trade.

Covering 32% of the planet, boreal forests are one of the last relatively intact terrestrial biomes, and are a critical carbon sink in global climate dynamics. Mature and old-growth boreal forests provide a large number of products that are culturally and economically important, from wood-based lumber, pulp, and fuel wood, to numerous nonwood products. Intensive wood harvest and conservation of naturally dynamic intact forests tend to be mutually exclusive; where biodiversity is highly valued, wood harvests are limited or banned outright. The authors of this Policy Forum advise that increasing domestic forest protection without decreasing demand for wood necessitates an increase in foreign imports, which introduces a negative impact on forest biodiversity elsewhere. In some cases, exporting impact across the border may cause negative impacts to boomerang back into the country's protected forests.

An intense search is under way to identify the ‘missing sink’ in the world carbon budget of perhaps 2 Pg year−1 (petagrams, or billion tonnes) of carbon, but its location and mechanism have proved elusive. Here we use a new forest inventory data set to estimate the carbon sink and the carbon pool of woody biomass in 55 countries that account for nearly all temperate or boreal forests and approximately half the world’s total forest area. In each country there was a net accumulation of biomass; together, the carbon sink of woody biomass was 0.88 Pg year−1 during the 1990s with estimated uncertainty from 0.71 to 1.1 Pg year−1. This estimate, already about half of the missing sink, would probably be even larger if carbon accumulation in soil and detritus were also accounted for, but we are unable to quantify that additional sink. The sink is twice that estimated for the woody biomass of these forests a decade ago due to higher estimates for tree growth throughout the region and decreased timber harvests in Russia. In contrast, the new data indicate a carbon pool that is smaller than earlier estimates because of improved data for Russia and Australia.

http://www.sciencedirect.com/science/journal/14693062 Strategies to mitigate anthropogenic climate change recognize that carbon sequestration in the terrestrial biosphere can reduce the build-up of carbon dioxide in the Earth’s atmosphere. However, climate mitigation policies do not generally incorporate the effects of these changes in the land surface on the surface albedo, the fluxes of sensible and latent heat to the atmosphere, and the distribution of energy within the climate system. Changes in these components of the surface energy budget can affect the local, regional, and global climate. Given the goal of mitigating climate change, it is important to consider all of the effects of changes in terrestrial vegetation and to work toward a better understanding of the full climate system. Acknowledging the importance of land surface change as a component of climate change makes it more challenging to create a system of credits and debits wherein emission or sequestration of carbon in the biosphere is equated with emission of carbon from fossil fuels. Recognition of the complexity of human-caused changes in climate does not, however, weaken the importance of actions that would seek to minimize our disturbance of the Earth’s environmental system and that would reduce societal and ecological vulnerability to environmental change and variability.

Several reports by Intergovernmental Panel on Climate Change (IPCC) have referred to published estimates ranging from 352 to 536 × 109 tons for the global pool of carbon in forest vegetation. However, a rounded estimate of 300 × 109 tons can be derived from the recent Global Forest Resources Assessment 2000 of the FAO, as shown in this paper. By comparing with independent empirical evidence as published in recent scientifi c literature and by considering sampling principles and the disturbance cycles of large forest regions, it is argued that the new lower estimate is more realistic. A downward correction of the estimate would make an important contribution to balancing the global carbon budget.

Debatt i HBL: Erik Wahlström: "Rio-avtalets konsekvenser" 6.6.1992 Jan Heino: "Kolbalansen i skogarna" 10.6.1992 Pekka Kauppi: "Skogarna och koldioxidfrågan" 17.6.1992

Vortrag im Symposium über Bewertung von Waldschäden infolge von Luftverunreinigungen. Gmunden, Österreich 13. -17. September 1988. IUFRO Arbeitsgruppe S4.04. -02.

Contribution to the International Co-operative Programme on the Assessment and Monitoring of Air Pollution Effects in Forests

For: Task force meeting on policy-oriented Assessment of impact of climatic variations. IIASA, Lazenburg, Austria 30 June – 2 July, 1986.

Seminar paper for: Seminar on machines and techniques for forest plant production, Tatranská Lomnica, High Tatras (Czechoslovakia) 20-24 June 1983.