Carbon stocks and greenhouse gas balance of harvested wood products: focus on the Asia-Pacific Partnership countries vis-à-vis the European Union

With the analytical tool, Frankfurt Harvested Wood Products Model, FPM, the carbon stocks and carbon stock changes of Harvested Wood Products, HWP, either in USE or in LANDFILLS L-F, have been evaluated, each separately, from the readily available statistical data base of the FAO, FAOSTAT, on the wood commodities: “Sawnwood and Wood-based Panels, SWP” and the paper commodities, “Paper and Paperboard, PAP”. The focus was on the newly founded Asia-Pacific Partnership countries for Clean Development and Climate (in short AP6), including Canada, which wants to join the AP6, in relation to the countries of the European Union EU-25. It could be shown that the stocks and stock changes of the HWP in USE follow a simple algorithm of the annual consumption or production and their mean annual growth, for the categories SWP and PAP, provided the mean residence times of the HWP in USE can be estimated. With the information on the fraction of residues entering the landfills and their estimated residence times an equivalent simple expression has been derived for stocks and stock changes of the HWP in LANDFILLS L-F. Their values have been calculated to be approximately 0.5 to 0.7 times smaller than those of the HWP in USE. Still, all stock changes of the HWP in L-F were positive and thus accumulating carbon. However, when methane outgasing within the HWP in L-F had been considered, the calculated Greenhouse Gas Balance was zero or negative under the estimated parameters thus to at least partly compensate the positive storage of carbon in HWP in USE. The percentage of CO₂ removed by the HWP in USE in comparison to the annual greenhouse gas emissions varied from 0.3 to 1.7%, with a mean value of 0.8% for the AP6 countries including Canada, in contrast to 1.0% of the EU-25 countries. Despite of the relative small magnitude in relation to the total emission of all GHG this contribution should not be neglected in the GHG Budget of a country.     

Global carbon dynamics of higher latitude forests during an anticipated climate change: Ecophysiological versus biome-migration view

The response of the vegetation and soils of the higher latitude forests and tundra ecosystems to an anticipated climate change is investigated using two alternative approaches to calculate the resulting change in the total carbon content (TCC) of the vegetation and the soils: On the one hand a BGC (bio-geochemical-cycle) model, in this case the FBM (Frankfurt Biosphere Model), where the ecosystem response is entirely due to the ecophysiological response of the vegetation and the ecological response of the soils. On the other hand a biome or “rule-based” model, in this case the BIOME model, which allows for the determination of the occurrence of a specific biome type from a given climatic situation assuming equilibrium conditions. Within the FBM prognosis net primary production and TCC are reduced both for needle leaved and broad leaved forests if the CO₂-fertilisation effect is not taken into account. When the CO₂-fertilisation effect is taken into consideration NPP, standing biomass and soil carbon are increased in a future greenhouse climate. Although there is a considerable shift of the biomes in response to the greenhouse climate within the BIOME approach, the TCC in the investigated northern biomes stayed more or less constant. This is due to a decrease in biomass in the southern regions of today's temperate forests compensating the biomass increase by the northward shift of the taiga border.     

Application of the stock change and the production approach to Harvested Wood Products in the EU-15 countries: a comparative analysis

With the analytical tool: Frankfurt Harvested Wood Products (HWP) Model, carbon stocks and carbon stock changes of HWP, either in USE or in LANDFILLS, have been evaluated from the readily available statistical data base of the FAO, FAOSTAT, on the wood commodities: “Sawnwood and Wood-based Panels” and the paper commodities: “Paper and Paperboard”. Essential differences have been found between the individual 15 EU countries in the comparison of the Stock Change Approach and the Production Approach, as well as in the comparison of the stock changes of HWP with the National Greenhouse Gas (GHG) budgets. The stock changes for the HWP in USE within the EU-15 Community have been calculated to be 10.83 Mt C/a (39.71 Mt CO₂/a) based on the Stock Change Approach and 9.81 Mt C/a (35.97 Mt CO₂/a) for the Production Approach, respectively. These numbers can be compared to the total GHG Inventory of the EU-15 of 4,095 Mt CO₂ equivalents, including all six Kyoto gases, which shows that the carbon sequestration of HWP in USE is of the order of 1% relative to GHG Inventory. The GHG balance for the carbon stock changes of HWP in LANDFILLS is of similar magnitude as for the HWP in USE, and therefore a sink when methane outgasing is disregarded. However, when methane outgasing is considered, which is formed as a 1:1 mixture with CO₂ under the prevailing anaerobic conditions the GHG balance results in minus 10.0 Mt C equivalent/a and minus 10.6 Mt C equivalent/a for the Stock Change Approach and the Production Approach under the parameters chosen in this study. Presented in Dublin, October 6–9, 2004, COST-21 Plenary Session.     

Contribution of temperate forests to the world's carbon budget

Temperate forests currently cover about 600 MHa, about half of their potential. Almost all these forests have been directly impacted by humans. The total living biomass in trees (including roots) was estimated to contain 33.7 Gt C. The total C pool for the entire forest biome was estimated as 98.8 Gt. The current net sink flux of biomass was calculated at 205 Mt yr^?1, with a similar amount removed in harvests for manufacture into various products. The major cause of this C sink is forest regrowth. Forest regrowth is possible because fossil fuels are the major source of energy in temperate countries, instead of fuelwood. Future C in these forests will be greatly influenced by human activity. Options to sequester more C include conservation of forest resources, activities that increase forest productivity such as adopting rotation ages to optimize C production, afforestation, improvement of wood utilization, and waste management.