Precipitation concentration in Jiangsu province, southeast China and its indicating function on the fluctuation of rice yield

Based on the precipitation record and single-crop rice yield data at 52 meteorological stations in Jiangsu province, southeast China from 1961 to 2012, a total of 14 precipitation concentration indices (PCI) during rice-growing period (May–October) were calculated, and then, the relationship between PCI and rice yield was explored. Results showed that: (1) the higher precipitation concentration was observed in north Jiangsu, and total precipitation was mainly concentrated in the rainstorm events and July rainfalls. (2) Precipitation concentration was increasing in recent 50 years, which was embodied in the significant increasing trends of precipitation contribution of rainstorm events and August rainfalls occurred in south Jiangsu. (3) The correlation analysis between rice yield and 14 PCI indicated that the precipitation contribution of rainstorm events (CDP6) was more suitable for accessing the losses of rice yield caused by excessive rainfall. (4) During the study period, the losses of rice yield in south Jiangsu exceeded 2%, owing to the stronger increasing trend of CDP6.