Analysis of Observed and DNDC Modeled Soil Respiration of Winter Wheat in Guanzhong Plain

The application of the DeNitrification-DeComposition (DNDC) model in soil respiration of winter wheat at the Ecological Experimental Station of Fuping County, China is researched for the year 2013-2014. The applied results indicate that DNDC is available to research soil respiration in cropland agroecosystems of Guanzhong Plain, China. Also the cumulative and seasonal variation emissions of soil respiration and components (root respiration, soil heterotrophic respiration) are estimated. Based on the simulated results, it can be seen that a significant variation appears in winter wheat growing season, where a downward trend starts from planting season to wintering season, and a steady low level at about 8.3 kg C·hm-2·d-1 keeps until the overwintering, then a significant upward to harvest, where the top point is almost 101.84 kg C·hm-2·d-1, with the total amount is 8342.35 kg C·hm-2. The seasonal amount of root respiration is 5345.47 kg C·hm-2, occupies 61.1% of soil respiration emissions.