• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Regional Environmental Change >Changes in the flood regime of Sao Francisco River (Brazil) from 1940 to 2006
【24h】

Changes in the flood regime of Sao Francisco River (Brazil) from 1940 to 2006

机译：1940年至2006年巴西圣弗朗西斯科河的洪水情势变化

获取原文
获取原文并翻译 | 示例
       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Flow regulation causes various environmental impacts in the downstream reaches of impounded rivers. The Sao Francisco River (SF) basin is Brazil's third most important watershed. Several dams have been built in its course in the last four decades, mostly for flow regulation and hydropower generation. This paper presents an evaluation of historical changes in the flood regime. Three regions of the SF River basin, which are under the influence of different levels of regulation, were studied: the lower, middle, and upper SF River. The components of magnitude, frequency, and duration of floods were quantified for each region from 1940 to 1960 (prior to the construction of the first dam) and from 1986 to 2006 (after the last dam). The results have shown the inexistence of big floods in the downstream areas, decreasing durations of small floods as well as significant changes in the annual seasonality of floods. Reductions in the flood frequency were verified in all stretches, even in non-regulated systems, such as the lower Velhas River. The climate variation, which occurred in both period, was not able to explain the changes in the flood regime of Sao Francisco River; therefore, dams and other anthropogenic activity are the main factors promoting the temporal variability of streamflows in the Sao Francisco basin.
机译：流量调节在蓄水河下游造成各种环境影响。圣弗朗西斯科河（SF）流域是巴西第三重要的分水岭。在过去的四十年中，已在此过程中建造了几座水坝，主要用于流量调节和水力发电。本文提出了对洪水制度历史变化的评估。研究了SF河流域的三个区域，它们受到不同级别的调节的影响：SF河的下游，中部和上部。从1940年到1960年（在建造第一座大坝之前）和1986年到2006年（在建造最后一座水坝之后）的每个区域，对洪水的大小，频率和持续时间进行了量化。结果表明，下游地区不存在大洪水，小洪水的持续时间减少，而且洪水的季节性季节性变化很大。甚至在非管制系统（例如下维尔萨斯河）中，在所有范围内都证实了洪水频率的降低。在这两个时期发生的气候变化无法解释圣弗朗西斯科河的洪水状态的变化。因此，水坝和其他人为活动是促进圣弗朗西斯科盆地水流时间变化的主要因素。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号