A Comprehensive Study of Agricultural Drought Resistance and Background Drought Levels in Five Main Grain-Producing Regions of China

Drought control and resistance affect national food security. With this in mind, we studied five main grain-producing regions of China: Sanjiang Plain, Songnen Plain, Huang-Huai-Hai Plain, the middle Yangtze River and Jianghuai region and Sichuan Basin. Using GIS technology, we evaluated the comprehensive agricultural drought situation based on major crops, the basic drought resistance by integrating multiple indicators and the comprehensive drought resistance against background agricultural drought. We chose spring wheat, winter wheat, early rice, late rice, single-season rice and maize as the research objects and calculated a crop composite drought index to determine that the agricultural drought degree was highest in the Huang-Huai-Hai Plain and slightly lower in the Sanjiang and Songnen Plains. The drought degree was relatively low in the middle Yangtze River and Jianghuai region and the Sichuan Basin. A remarkable difference was observed in agricultural drought resistance among the grain-producing areas. The entire Sanjiang Plain had the lowest agricultural drought resistance, and that of the Songnen Plain was slightly higher. In the Sichuan Basin, many areas had lower and intermediate values of drought resistance. In the Huang-Huai-Hai Plain and middle Yangtze River and Jianghuai region, resistance was stronger. The ranking of comprehensive drought resistance from strongest to weakest was Huang-Huai-Hai Plain > middle Yangtze River and Jianghuai region > Sichuan Basin > Songnen Plain > Sanjiang Plain. Finally, the sensitivity analysis was carried out to discuss the sensitive factors significantly affecting the agricultural drought resistance.