Roy Suvendu, Sahu Abhay Sankar
Department of Geography, University of Kalyani, Kalyani, Nadia, 741235, West Bengal, India.
Department of Geography, University of Kalyani, Kalyani, Nadia, 741235, West Bengal, India.
J Environ Manage. 2017 Jul 15;197:316-330. doi: 10.1016/j.jenvman.2017.04.012.
Extension of transport networks supports good accessibility and associated with the development of a region. However, transport lines have fragmented the regional landscape and disturbed the natural interplay between rivers and their floodplains. Spatial analysis using multiple buffers provides information about the potential interaction between road and stream networks and their impact on channel morphology of a small watershed in the Lower Gangetic Plain. Present study is tried to understand the lateral and longitudinal disconnection in headwater stream by rural roads with the integration of geoinformatics and field survey. Significant (p < 0.001) growth of total road length and number of road-stream crossing in the last five decades (1970s-2010s) contribute to making longitudinal and lateral disconnection in the fluvial system of Kunur River Basin. Channel geometry from ten road-stream crossings shows significant (p = 0.01) differences between upstream and downstream of crossing structure and created problems like downstream scouring, increased drop height at outlet, formation of stable bars, severe bank erosion, and make barriers for river biota. The hydro-geomorphic processes are also adversely affected due to lateral disconnection and input of fine to coarse sediments from the river side growth of unpaved road (1922%). Limited streamside development, delineation of stream corridor, regular monitoring and engineering efficiency for the construction of road and road-stream crossing might be effective in managing river geomorphology and riverine landscape.
交通网络的扩展有利于良好的可达性,并与区域发展相关联。然而,交通线路分割了区域景观,扰乱了河流与其洪泛区之间的自然相互作用。使用多个缓冲区进行空间分析,可提供有关道路网络与溪流网络之间潜在相互作用及其对恒河下游平原一个小流域河道形态影响的信息。本研究试图通过整合地理信息学和实地调查,了解乡村道路对源头溪流造成的横向和纵向断开情况。在过去的五十年(20世纪70年代至21世纪10年代)中,道路总长度和道路与溪流交叉点数量显著增长(p < 0.001),这导致库努尔河流域水系出现纵向和横向断开。对十个道路与溪流交叉点的河道几何形状分析表明,交叉结构上下游存在显著差异(p = 0.01),并引发了诸如下游冲刷、出水口落差增加、稳定沙洲形成、严重河岸侵蚀等问题,还为河流生物群设置了障碍。横向断开以及未铺砌道路沿线(1922%)从细颗粒到粗颗粒沉积物的输入,也对水文地貌过程产生了不利影响。有限的溪边开发、溪流廊道的划定、定期监测以及道路和道路与溪流交叉点建设的工程效率,可能对管理河流地貌和河流景观有效。