地理学报 ›› 2018, Vol. 73 ›› Issue (1): 104-114.doi: 10.11821/dlxb201801009

• 地表过程与生态环境 • 上一篇    下一篇

平原水网地区快速城市化对河流水系的影响

吴雷1,2(),许有鹏1(),徐羽1,袁甲1,项捷1,徐兴3,徐勇4   

  1. 1. 南京大学地理与海洋科学学院,南京 210023
    2. 澳大利亚国立大学社会与环境学院, 堪培拉 ACT 0200
    3. 江苏省水文水资源勘测局无锡分局,无锡 214000
    4. 江苏省水文水资源勘测局苏州分局,苏州 215000
  • 收稿日期:2017-04-07 出版日期:2018-01-31 发布日期:2018-01-31
  • 基金资助:
    国家重点研发计划专项项目(2016YFC0401502);国家自然科学基金项目(41371046, 41771037);江苏省水利科技基金项目(2015003)

Impact of rapid urbanization on river system in a river network plain

WU Lei1,2(),XU Youpeng1(),XU Yu1,YUAN Jia1,XIANG Jie1,XU Xing3,XU Yong4   

  1. 1. Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210023, China
    2. Fenner School for Society and Environment, Australian National University, Canberra, ACT 0200, Australia
    3. Wuxi Sub-bureau of Jiangsu Province Hydrology and Water Resources Investigation Bureau, Wuxi 214000, Jiangsu, China
    4. Suzhou Sub-bureau of Jiangsu Province Hydrology and Water Resources Investigation Bureau, Suzhou 215000, Jiangsu, China
  • Received:2017-04-07 Online:2018-01-31 Published:2018-01-31
  • Supported by:
    National Key Research and Development Plan, No.2016YFC0401502;National Natural Science Foundation of China, No.41371046, No.41771037;Water Conservancy Science and Technology Foundation of Jiangsu Province, No.2015003

摘要:

为了揭示平原水网地区快速城市化对河流水系的影响,基于1:50000地形图和30 m空间分辨率遥感影像数据,采用格网化河网密度、支流发育系数和分形维数等水系指标,分析了20世纪80年代至21世纪10年代苏州市河流水系的时空变化特征,探讨了土地城市化水平与河网密度变化之间的定量关系。结果表明:① 苏州市河流长度衰减了10.55%,其中干流长度增加了3.24%,一级支流与二级支流的长度分别减少了18.87%和11.76%;河网密度在空间上以减小为主,其中干流河网密度在空间上以增加为主,支流河网密度在空间上以减少为主。② 支流发育系数由3.36下降至2.78,水系结构趋于主干化;水系分形维数由1.70下降至1.63,水系形态趋于简单化。③ 土地城市化率高于40%时,河流水系衰减趋于明显,且土地城市化水平越高,河流减少的越多。为满足不同的经济社会发展需要,不同等级河流对土地城市化的响应不尽相同:为提高城市防洪排涝能力,一级河流总体上有所增加;土地城市化率小于40%时,部分二级河流被侵占以增加耕地面积,并新开挖了许多三级河流以提高农田排涝与灌溉能力;土地城市化率大于40%时,大量支流被填埋并转换为建设用地,而且等级越低的河流衰减的越严重。

关键词: 河流水系, 城市化, 格网化河网密度, 平原水网地区, 苏州市

Abstract:

To reveal the impact of rapid urbanization on river system in a river network plain, characteristic indexes of river system, such as grid river density, development coefficient of tributary and fractal dimension, were used to evaluate the temporal and spatial changes of river system in Suzhou City from 1980s to 2010s, based on topographic map in 1:50000 scale and remote sensing image in 30m scale. The results were as following: The length of river system was decreased by 10.55%. From view of each order river, the length of 1st order river was increased by 3.24%, while that of 2nd order river and 3rd order river was decreased by 18.87% and 11.76%, respectively. The grid river density of river system was mainly decreased across most area of this region, and the change trend between main river and tributary was opposite in space, i.e., the grid river density of main river was mostly increased, while that of tributary was mostly decreased. The development coefficient of tributary and fractal dimension of river system respectively changed from 3.36 to 2.78 and 1.70 to 1.63, which indicated that the structure and morphology of river system became simplified. The attenuation of river system became remarkable when the land urbanization rate was greater than 40%. The response to land urbanization for each order river was different. Overall, 1st order river experienced a slight increase, to enhance the capability of flood control and drainage. When the land urbanization rate was less than 40%, some 2nd order rivers were occupied by farmland, and many 3rd order rivers were dug to improve the capacity of drainage and irrigation. When the land urbanization rate was greater than 40%, a lot of tributaries were buried and converted to construction land. And the lower the order river, the more severe the attenuation was.

Key words: river system, urbanization, grid river density, river network plain, Suzhou City