Acta Geographica Sinica ›› 2016, Vol. 71 ›› Issue (3): 448-458.doi: 10.11821/dlxb201603008

• Meteorology and Hydrology • Previous Articles     Next Articles

Influence of stream structure change on regulation capacity of river networks in Taihu Lake Basin

Yuefeng WANG(), Youpeng XU(), Qianyu ZHANG, Guang LI, Chaogui LEI, Liu YANG, Longfei HAN, Xiaojun DENG   

  1. School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China
  • Received:2015-08-04 Revised:2016-01-01 Online:2016-03-25 Published:2016-03-25
  • Supported by:
    National Natural Science Foundation of China, No.41371046;The Commonwealth and Specialized Program for Scientific Research, Ministry of Water Resources of China, No.201301075;Natural Science Foundation of Jiangsu Province, No.BK20131276;Water Conservancy Science and Technology Foundation of Jiangsu Province, No.2015003;The Graduate Research and Innovation Projects in Jiangsu Province, No.KYLX15_0041


River network system was heavily damaged during the rapid urbanization in the Taihu Lake Basin in recent decades. A large number of rivers were buried and disappearing, which changed the hydrological process of the basin. Regulation capacity of river networks is an important factor for flood disaster mitigation. Based on river networks data derived from the topographic map in the 1960s, 1980s and 2010s at a scale of 1:500000 and water level data of three hydrological stations from 1960 to 2010, we selected a list of indices, such as drainage density (Rd), water surface ratio (Wp), box dimension (D) and Hurst index (H) to analyze the changes of river networks and its regulation capacity in Wuchengxiyu region during the past 50 years. What's more, the relationship was established between the regulation capacity of river networks and the indices of stream structure using the Hurst index and the principles of Representative Elementary Watershed (REW) Model. Results showed that: (1) the Rd, Wp, and D decreased by 18.87%, 24.59% and 7.60% in the past 50 years respectively due to the process of urbanization, and the reduction of three stream structure indices from the 1980s to 2010s was higher than that during the 1960s to 1980s. (2) The Hurst index of water level was used to describe the regulation capacity of river networks and was calculated through the R/S analysis of the time series. Decreasing trends of the Hurst index were detected during annual and wet season, which indicated that the regulation capacity of river networks was gradually reduced due to urbanization. (3) The relationship between the indices of river networks and its regulation capacity was established through the concept of REW and Hurst index. The calibration and validation was carried out for this relationship with relevant data. This work will provide a simple and practical method to assess regulation capacity of river networks.

Key words: stream structure, regulation capacity of river networks, representative elementary watershed, urbanization, Taihu Lake Basin