Author(s): Peiyu Liang; Xuan Wang
Linked Author(s):
Keywords: Streamflow trend; Seasonal streamflow distributions; Mann-Kendall method; Chaohe River
Abstract: The trend variation of the river streamflow reflects the influence of environmental change on regional hydrological processes. As a main tributary of the Miyun Reservoir, the Chaohe River has been seriously affected by climate change and human activities, leading to significant streamflow variation since 1960s. In this paper, we analyze the trend variation of annual and seasonal streamflow, as well as the trend of seasonal distribution proportions of streamflow in the Chaohe River from 1963 to 2011 by using the Mann-Kendall method. Then the F-test method is introduced for significance test of the streamflow variation. The results are as follows. (1) Seasonal and annual streamflow has continuously declined during 1963-2011 in the Chaohe River. (2) Three stages of the streamflow variation are found: fluctuations before 1980; a tiny upward trend from 1980s to 1990s; and a downward trend in 2000s with the year of 1998 as a significant aberrance point. (3) The distribution proportion for summer streamflow has a downward trend, while distribution proportions for both autumn streamflow and winter streamflow have upward trends, and that for spring streamflow has no trend at 95% confidence level. This indicates that significant variations of streamflow in the Chaohe River have occurred and summer streamflow has the largest decline in the past 50 years. It will help to reveal the relationship between water resources and changing environment, and provide a basis for making decision related to water resources risk management in this basin.
Year: 2013