Modeling the Impacts of Soil Organic Carbon Content of Croplands on Crop Yields in China

This study quantified the impacts of soil organic carbon (SOC) content on the grain yield of crops using a biogeochemical model (DNDC, denitrification-decomposition). Data on climate, soil properties, and farming management regimes of cropping systems were collected from six typical agricultural zones (northeast, north, northwest, mid-south, east and southwest regions of China, respectively) and integrated into a GIS database to support the model runs. According to the model, if the initial SOC content in the cropland was increased by 1 g C kg−1, the crop yield may be increased by 176 kg ha−1 for maize in the northeast region, 454 kg ha−1 for a maize-wheat rotation in the north region, 328 kg ha−1 for maize in the northwest region, 185 kg ha−1 for single-rice in the mid-south region, 266 kg ha−1 for double-rice in east region, and 229 kg ha−1 for rice and wheat rotation in southwest region. There is a great potential for enhancing the crop yield by improving the SOC content in each region of China.