Author(s): Yanying Shao; Zhiyong Yang
Linked Author(s):
Keywords: Runoff variation; Climate change; Human activities; Attribution recognition
Abstract: The influence of the global change and human activity is increasing in the water cycle system, it is more obvious on the coupled nature-society evolution characteristic of water cycle. Surface runoff is an important process in water circulation and more sensitive to response the coupled nature-society water cycle. It is very important to quantify identification of the impact of climate change and human activities on runoff for both management of water resource and risk evaluation of disaster of flood and drought. In this paper, Mann-Kendall rank test is used to detect the change point of annual runoff for the period of 1961-2010 in Xiang River, and a change point around 1990 is found. From this point, a method based on the coupled water-energy balance of Fu’s equation was employed to estimate the impact of climate change and human activities on the change of runoff, which is largely affected by the dual-factor of climate change and human activities. The results show that Compared to the baseline period of 1961-1990, the increase of runoff was 95. 6mm in 1991-2010, climate change did a dominant contribution of about 64% to the increase of runoff, while human activities account for 36% of the increase in mean annual runoff for the same period. Increase of precipitation was the major reason for the significant increase of runoff. Our study also indicates that the coupled water-energy balance of Fu’s equation can be considered to be a quick and easy approach. Human activities such as increase of the land used in the constructions and reduction of vegetation coverage ratio are the other reason of the increasing of runoff.
Year: 2013