Heterogeneous Precipitation and Streamflow Trends in the Xiangxi River Watershed, 1961–2010

Abstract

This study aims to perform a comprehensive trend analysis of precipitation and streamflow at the watershed scale. Multiple techniques were employed to examine the temporal trends in annual, seasonal, and monthly precipitation as well as streamflow in the Xiangxi River watershed, China. Results showed that heterogeneous trends existed in precipitation and streamflow. To be specific, statistically insignificant trends in annual and seasonal precipitation were discovered, but varying monthly precipitation exhibited complex changes, especially for the decreasing precipitation in September. Annual and autumn average streamflow in addition to monthly streamflow in April, May, September, October, and November were found to experience a downward trend. Also, negative trends were detected in all low flow statistics, including annual minimum instantaneous streamflow;