Aggregated estimation of basic parameters of biological production and thecarbon budget of Russian terrestrial ecosystems: 2. Net primary production

The estimated net primary production (NPP) of Russian terrestrial ecosystem s (annual average over the period from 1988 to 1992) is 9544 Tg of dry matt er, or 4353 Tg of carbon. Of the total amount, forests account for approxim ately 39.2% there and below comparisons are made with respect to carbon con tent); natural grasslands and brushwoods, for 27.6%; farmlands (arable land and cultivated pastures), for 22.0%; and wetlands, for 11.2%. The average NPP density on lands covered with vegetation (1629.8 million hectares in Ru ssia) is 267 g C/m(2) per year. The highest value (498 g C/m(2) per year) i s characteristic of arable lands. Other land-use/land-cover (LULC) classes have the following NPP densities tin areas covered with vegetation): grassl ands and brushwoods, 278 g C/m(2); forests, 224 g C/m(2); and wetlands, 219 g C/m(2) per year. In general, Russian terrestrial ecosystems accumulate 5 9.7% of the total NPP in the aboveground phytomass (47.8% in green parts an d 11.9% in wood) and 40.3% in the underground phytomass. The latter paramet er differs significantly in different LULC classes and bioclimatic zones. A ccording to calculations, the uncertainty in estimating the total NPP is 11 % (a priori confidential probability 0.9).