Centre for Earth Science Studies, Thiruvananthapuram, India.
Environ Manage. 2011 Jan;47(1):130-40. doi: 10.1007/s00267-010-9571-6. Epub 2010 Oct 7.
In the past few decades, the demand for construction grade sand is increasing in many parts of the world due to rapid economic development and subsequent growth of building activities. This, in many of the occasions, has resulted in indiscriminate mining of sand from in-stream and floodplain areas leading to severe damages to the river basin environment. The case is rather alarming in the small catchment rivers like those draining the southwestern coast of India due to limited sand resources in their alluvial reaches. Moreover, lack of adequate information on the environmental impact of river sand mining is a major lacuna challenging regulatory efforts in many developing countries. Therefore, a scientific assessment is a pre-requisite in formulating management strategies in the sand mining-hit areas. In this context, a study has been made as a case to address the environmental impact of sand mining from the in-stream and floodplain areas of three important rivers in the southwestern coast of India namely the Chalakudy, Periyar and Muvattupuzha rivers, whose lowlands host one of the fast developing urban-cum-industrial centre, the Kochi city. The study reveals that an amount of 11.527 million ty(-1) of sand (8.764 million ty(-1) of in-stream sand and 2.763 million ty(-1) of floodplain sand) is being mined from the midland and lowland reaches of these rivers for construction of buildings and other infrastructural facilities in Kochi city and its satellite townships. Environmental Impact Assessment (EIA) carried out as a part of this investigation shows that the activities associated with mining and processing of sands have not only affected the health of the river ecosystems but also degraded its overbank areas to a large extent. Considering the degree of degradation caused by sand mining from these rivers, no mining scenario may be opted in the deeper zones of the river channels. Also, a set of suggestions are made for the overall improvement of the rivers and its biophysical environment.
在过去的几十年中，由于世界许多地区经济快速发展和建筑活动的增长，对建筑用砂的需求不断增加。在许多情况下，这导致了从河流和洪泛区滥采滥挖沙子，对河流流域环境造成了严重破坏。在印度西南部的小流域河流中，这种情况尤其令人震惊，因为它们的冲积层中沙子资源有限。此外，由于缺乏有关河流采砂对环境影响的充分信息，这是许多发展中国家监管工作面临的主要难题。因此，在受采砂影响的地区制定管理策略之前，必须进行科学评估。在这种情况下，进行了一项研究，以解决印度西南部三条重要河流（即 Chalakudy、Periyar 和 Muvattupuzha 河）的河流和洪泛区采砂对环境的影响，这些河流的低地是一个快速发展的城市和工业中心——科钦市的所在地。研究表明，从这些河流的中游和下游地区开采了 1152.7 万吨沙子（876.4 万吨河道内沙子和 276.3 万吨洪泛区沙子），用于科钦市及其卫星城镇的建筑和其他基础设施建设。作为本研究的一部分进行的环境影响评估（EIA）表明，与采砂和加工相关的活动不仅影响了河流生态系统的健康，而且在很大程度上还破坏了其漫滩地区。考虑到这些河流采砂造成的退化程度，在河流的较深区域可能无法选择任何开采方案。此外，还提出了一系列建议，以全面改善河流及其生物物理环境。
