Simulated carbon and nitrogen contents in arid farmland ecosystem in Chinausing dinitrification-decomposition model

The denitrification-decomposition (DNDC) model was used to elucidate the ca rbon (C) and nitrogen (N) characteristic in arid farmland ecosystem on loes s plateau in China: Carbon and N were determined in soil of a winter wheat field ecosystem in successive six years, under four different treatments. T he results indicated that manure was better to the C and N accumulation in soil than N fertilization when one type of fertilizer was applied. Nitrogen could enhance C and N cycling intensities. Carbon and N cy cling were also affected by annual precipitation, whereas nitrogenous fertilizer applicati on favored carbon cycling. Under water deficit conditions, manure was bette r than other fertilizers to the cycling of carbon. By comparing with known experiment results and measured data obtained on loess plateau, it was moti oned that the DNDC model was applicable.