Changes in Event-Based Rainfall-Runoff-Sediment and the Relationships between These Changes and Rainfall Intensity and Vegetation Coverage Variations in Loess Plateau of China
It is important to analyze the changes in event-based rainfall-runoff-sediment and the relativities between these changes and rainfall intensity and vegetation coverage variations in the Loess Plateau of China for recognizing the causes of changes in water and sediment of the Yellow River.This study collected 753 event-based hydrological data of 16 years,12 watersheds located in the Loess Plateau of China,using four indicators,including rainfall intensity,vegetation coverage runoff coefficient,and sediment coefficient,and analyzed the changes in event-based rainfall-runoff-sediment and the relativities between these changes and rainfall intensity and vegetation coverage variations in the Loess Plateau of China.Results showed that:① the rainfall-runoff and runoff-sediment relationships changed significantly in the period from 2006 to 2011 compared to the period from 1980 to 1989,and the runoff and sediment generation capacities of most watersheds decreased.The runoff coefficient and sediment coefficient of eight in ten watersheds decreased 25.93％-66.1％ and 59.05％-97.71％,respectively;② By analysing the relativities between rainfall intensity,vegetation coverage variations and runoff,sediment changes,we found that the vegetation coverage variation was stronger than rainfall intensity change related to the runoff and sediment changes,and it was indicated that the effect of vegetation coverage variation on runoff and sediment changes was more obvious;③) we also discussed the sensibilities of runoff and sediment yield changes on vegetation coverage variation in different dryness/wetness,and found that the wetter the climate,the more sensitive the variations of runoff and sediment yield on the change of vegetation coverage were,and the more obvious the reductions of runoff and sediment by vegetation improvement generated.
rainfall eventrunoffsediment yieldrainfall intensityvegetation coverageLoess Plateau of China
国家科技期刊平台
NSTL
万方数据
维普
