Application of the DNDC model for estimation of carbon and nitrogen exchange parameters in arable soils in Non-Chernozem Zone
The approbation of the DNDC (DeNitrification-DeComposition) model was done with the aim to estimate an opportunity of model using for analysis of carbon and nitrogen exchange and greenhouse gases dynamics in agroecosystems of arable soils in the Central Non-Chernozem Zone of Russia. The research can be divided into two blocks: estimation of model sensitivity and its verification on the base of field experiments data and statistical calculations. This article presents the results of analysis of model sensitivity to input parameters change. It is shown that in the Russian Non-Chernozem Zone the amount of fertilizers is the most important factor influencing on regional carbon and nitrogen biogeochemical cycles and the greenhouse gases emission. Annual increase of soil organic carbon content depends on weather conditions and soil texture (clay fraction). Carbon dioxide emission isensitive to crops biological characteristics and tillage intensity. According to modeling data, in the Non-Chernozem Zone's agrocenoses methane is primarily absorbed by soil. The concentration of nitrous oxide is more sensitive to tillage and fertilizing than to amount of precipitation, and its annual values fluctuate in a small range.