Modeling Climate Change Effects on Rice Yield and Soil Carbon under Variable Water and Nutrient Management

Soil organic carbon (SOC) conservation in agricultural soils is vital for sustainable production and climate change mitigation. To project changes of SOC rice yield under different water management future climates, based on a two-year (2015 2016) field test Kunshan, China, the Denitrification Decomposition (DNDC) model was modified validated soil moisture module DNDC improved to realize simulation conditions water-saving irrigation. Four models four representative concentration pathways (RCP 2.6, RCP 4.5, 6.0, 8.5), which were integrated from fifth phase Coupled Model Intercomparison Project (CMIP5), ensembled by Bayesian Averaging (BMA) method. The results showed that can effectively simulate SOC, dissolved (DOC), irrigation fertilizer systems. normalized root mean squared errors DOC 3.45–17.59% 8.79–13.93%, respectively. efficiency coefficients close 1. scenarios had great impact yield, whereas less than measures SOC. average yields all 8.5 2090s decreased 18.41%, 38.59%, 65.11%, 65.62%, respectively, compared with those 2020s. long-term effect content paddy fields minimal. treated conventional initially then remained unchanged, while other treatments increased obviously time. Compared traditional management, controlled straw returning clearly fields. Thus, this system recommended