Temporal Distribution Characteristics of Rainfall Erosivity in Qilin District of Qujing City

Distribution characteristics of rainfall and erosive rainfall were analyzed by using daily rainfall data in Qilin District of Qujing City from 2000 to 2016. Rainfall erosivity of Qilin District were calculated by rainfall erosivity models based on daily rainfall and the annual and inter annual distribution characteristics of rainfall erosivity were studied. The results indicate that mean annual rainfall is 875.5 mm, maximum annual rainfall is 1 246 mm and minimum is 533.9 mm. The annual rainfall of distribution curve is a single peak. Rainfall is mainly distributed from May to October and taking 85.47% of total annual rainfall. The erosive rainfall is mainly distributed from May to October and taking 90% of total annual erosive rainfall. The maximum of erosive rainfall is June and taking 26% of total annual erosive rainfall. The maximum of secondary rainfall erosivity from 2000 to 2016 is 1 491.54 MJ·mm/(hm²·h) and taking 2.35% of total rainfall erosivity, with the mean of 158.7 MJ·mm/(hm²·h). The mean monthly rainfall erosivity is 31.87-1 127.94 MJ·mm/(hm²·h). The maximum of proportion of rainfall erosivity is June and taking 29% of total rainfall erosivity, and the minimum is February. The seasonal rainfall erosivity is summer>autumn>spring>winter. The mean annual rainfall erosivity is 3 734.19 MJ·mm/(hm²·h) and the interannual variation is significant. There is a good power relationship between rainfall erosivity and erosive rainfall and R² is more than 0.9.