The Finnish Forest Research Institute (Metla) has developed computing models for estimating the forest carbon balance. The models have been applied to national carbon balance calculation. The models are suitable for assessing biomass in tree stands and other vegetation, litterfall of needles and branches, and accumulation and release of carbon by soils of upland forests. This research also determined uncertainties in the national carbon inventory calculations. The major uncertainties concern assessment of soil carbon sink, which is one of the most unreliable parts in the greenhouse gas (GHS) inventories also in other countries.
The tree species- and age-specific biomass expansion factors used in biomass equations were tested regarding their suitability for national carbon balance calculation; the tests were performed in collaboration with the Swedish national forest inventory team. The research showed that specified models must be developed for each vegetation zone and that biomass estimations involve the greatest uncertainty for young forests.
Metla’s research group also provided their expertise when suitable methods were developed for biomass assessment in Central Europe. As a result of the researcher exchange funded by the Academy of Finland , models were created for calculation of Norway spruce biomass as part of a GHG inventory in the Czech Republic.
Additionally, possibilities for using remote sensing methods in biomass assessment were studied. The investigation showed that the ASTER satellite images recorded in nine different wavelength channels is suitable for making biomass estimates of boreal forests.
The Metla research group also organized an international workshop in April 2006 with funding provided by the European Science Foundation (ESF). The aim of the event is to seek means to improve large-scale carbon sink assessments of forest soil through international collaboration.
he work of the research group will be continued in a new project called ”Interlinkages between forest biodiversity and carbon sequestration”. The project objectives include studying the linkages between forest carbon sinks and maintenance of biodiversity, as well as analysing the impact of various forest management options on carbon sequestration by tree stand and soil in the changing climate. The study will include modelling calculations on the dependence of litterfall on the tree growth and the probability of natural drainage in excessively dense forests.