地理学报 ›› 2016, Vol. 71 ›› Issue (3): 448-458.doi: 10.11821/dlxb201603008

• 气象水文 • 上一篇    下一篇

太湖平原区河网结构变化对调蓄能力的影响

王跃峰(), 许有鹏(), 张倩玉, 李广, 雷超桂, 杨柳, 韩龙飞, 邓晓军   

  1. 南京大学地理与海洋科学学院,南京 210023
  • 收稿日期:2015-08-04 修回日期:2016-01-01 出版日期:2016-03-25 发布日期:2016-03-30
  • 作者简介:

    作者简介:王跃峰(1987-), 男, 山东临清人, 博士, 主要研究方向为流域水文与水资源.E-mail: wyf2046@163.com

  • 基金资助:
    国家自然科学基金项目(41371046);水利部公益性行业科研专项经费项目(201301075);江苏省自然科学基金项目(BK20131276);江苏省水利科技基金(2015003);江苏省普通高校研究生科研创新计划项目 (KYLX15_0041)

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:2016-03-30
  • 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

摘要:

城镇化快速发展导致河网水系萎缩,连通性受阻,河网调蓄能力降低,加大了区域洪灾风险和洪涝损失.基于1960s,1980s,2010s的1:5万地形图水系及三个控制站的水位数据,选取河网密度(Rd),水面率(WP),盒维数(D),水位Hurst指数(H),分析了近50年来太湖流域武澄锡虞地区的水系演变与河网调蓄能力变化;并借助代表性单元流域概念,以水位Hurst指数来表征河网调蓄能力,从河网调蓄的物理机理出发,探讨了河网调蓄与河网结构参数的关系.结果表明:① 受快速城镇化影响,1960s-2010s武澄锡虞地区河网密度,水面率及盒维数分别下降了18.87%,24.59%,7.60%,且1980s至2010s各水系指标的衰减率均高于1960s-1980s;② 1960-2010年,研究区年均及汛期的水位Hurst指数呈下降趋势,其所反映的河网调蓄能力与该地区河网水系各指标变化同步,这表明城镇化引起的河流水系衰减导致河网调蓄能力发生明显下降,非汛期水位Hurst指数先增加后降低,表现出一定的不确定性;③ 基于REW概念与水位Hurst指数值,初步构建了河网结构参数与调蓄能力的关系式,并对关系式进行了验证,基本可行,可在一定程度上揭示城镇化下水系变化对河网调蓄能力的影响,从而为评价平原水网区河网调蓄能力提供了一种相对简便的方法.

关键词: 河网结构, 调蓄能力, REW概念, 城市化, 太湖流域

Abstract:

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