Potential Impact of Climate Change on Rained Agriculture of Ningxia

摘要

Rain fed agriculture in Ningxia is one of the most vulnerable sector to climate change, as the available water and land resources are limited and most of the province's land is arid. In this study, a crop simulation model (DSSAT) was used to assess the impact of climate change scenario on rainfed maize and potato in the southern mountain areas in Ningxia. Analysis of observed crop data showed differences between cultivated and harvested areas for both crops in the study area with variations among years. Results from DSSAT model for years showed that it was able to capture the trend of yield over the years realistically well. The model predicted an average yield of maize of 5450 kg/ha, which was close to the average (5446kg/ha) yield reported by the Department of statistics of Ningxia (DOSN) and an average predicted yield of potato was 2350 kg/ha while the DOSN average was 2358 kg/ha, with higher RMSE for maize (1046kg/ha) than for potato (358kg/ha). Predictions of future yield for both crops showed that the responses of maize and potato were different under different climate changes scenarios. The reduction of rainfall by 10-20% reduced the expected yield by 7-12% for maize and 9-18% for potato, respectively. The increase in rainfall by 10-20% increased the expected yield by5-9% for maize and 10-20% for potato, respectively. The increase of air temperature by 1,2,3 and 4℃ resulted in deviation from expected yield by-3.3, -0.27.+6.1 and +12.5 % for maize and -18.4, -15.7, -8 and +0.4 % for potato, respectively. These results indicated that potato would be more negatively affected by the climate changes scenarios and therefore adaptation plans should prioritize the areas cultivated with this crop.