三峡工程运行前后的长江中游河段冲淤变化(1975-2017年)     

李少希  杨云平  张华庆  朱玲玲  朱玉德  张明进 《湖泊科学》2021,33(5):1520-1531

气候变化和流域人类活动等综合影响改变了河道演变的自然进程,尤其是流域大型水库的影响,深刻改变了下游的水沙通量与河道演变过程及趋势.以三峡工程为对象,研究坝下游水沙通量及河道演变过程对三峡工程运行的响应关系,可加深大型水利枢纽运行对下游河道演变影响的认识.本文以长江中游河段（宜昌-湖口河段）为研究对象,分析1975-2017年河道冲淤变化,结果表明：近40年来,长江中游河床已发生了累积性的冲刷,近坝段砂卵石河段冲刷强度先增强后减弱,沙质河段冲刷强度呈增强态势.三峡工程运行后不同河型演变特征归纳为：分汊河段江心洲以冲刷为主,上荆江河段内实施的航道整治工程稳定了江心洲形态,但面积受清水下泄的影响呈减小态势,枯水期主汊分流比呈减小态势,部分汊道发生了主支汊交替变化;下荆江及下游分汊河段江心洲面积虽然交替变化,整体上航道整治工程控制了江心洲规模;弯曲河段凸岸侧边滩以冲刷为主,急弯段的凹岸侧深槽淤积,微弯段凸岸边滩冲刷,对应的凹岸侧深槽相对稳定.  相似文献   

南水北调西线一期工程区达曲流域泥石流及发展趋势     

柳金峰  欧国强  游勇  吕娟 《山地学报》2005,23(6):719-724

南水北调西线一期工程区位于青藏高原的东北缘,具有复杂的地形地貌、岩性和区域构造背景,受自然因素控制和人类活动影响,尤其是工程建设对山地表层大规模的扰动,泥石流将成为工程施工和运行期间的重要灾害。通过野外考察和调查,查明了达曲流域的泥石流分布情况,得出达曲流域泥石流具有规模中等,危害严重;以冲为主,冲淤强烈;泥石流固体物质粒径粗;泥石流活动频率较低等特点。并在此基础上,分析了达曲流域泥石流的发展趋势。  相似文献   

Water-saving potential evaluation of water-receiving regions in Shandong province on the East Route of the South-to-North Water Transfer Project of China          下载免费PDF全文

YIN Xiao-lin  GAO Yuan-yuan  WU Hai-ping  ZHAO Xue-ming 《地下水科学与工程》2020,8(3):287-297

Taking 13 water-receiving areas on the East Route of the South-to-North Water Diversion Project (ERSNWDP) in Shandong Province as the study area, and comparing it with Jiangsu Province on the ERSNWDP and the Middle Route of the South-to-North (MRSNWDP), the current water-saving potential of the water-receiving areas within the municipalities of Shandong was analyzed. Different water-saving scenarios were constructed and analyzed with key water-saving indexes in various industries. These indexes include the effective utilization coefficient of farmland irrigation water, total water consumption of industrial sectors with an added value of over 10 000 RMB, average leakage rate of the urban public water supply pipe network and the penetration rate of water-saving appliances. Based on the scenarios, comprehensive water-saving potential of the 13 water-receiving area cities was calculated. The results show that the water-saving potential of the study area is at a relative high level. However, some cities still have a certain amount of water-saving potential for agriculture and industry to be elevated. Under the recommended water-saving scenario, the water-saving potential is 1.134 billion m³, accounting for 5.33% of the current total water consumption, of which 460 million m³ is in agriculture, 600 million m³ in industry, is and 74.20 million m³ in urban domestic sector. Comprehensive water-saving measures for the study area were proposed from the aspects of agricultural, industrial and domestic water uses. Agricultural and industrial water saving are more significant. The major cities for agricultural water saving include Jining City, Heze City, Weifang City and Jinan City; the focus cities of industrial water saving mainly include Weihai City, Jining City and Qingdao City and etc.; the key water-saving areas for urban use mainly include Zaozhuang City, Jining City and Heze City.  相似文献   

引水补源工程对黛溪河流域地下水补给效果浅析     

万军伟  王明珠  刘志涛  杨亚宾  刘毅  赵书兴 《中国地质调查》2020,7(6):86-95

南水北调是国家级的重大水利工程,调水效果最终依赖于接收调水地区对调水的具体利用,引水补源工程是南水北调工程在邹平市的具体利用。为评价引水补源工程对黛溪河流域地下水的补给效果,在分析邹平市引水补源工程实施后黛溪河流域地下水资源的各个补给项的基础上,采用水均衡法计算各个地下水补给量,确定了黛溪河流域引水补源的总补给量。将总补给量视为本区地下水可开采资源量,将地下水可开采资源量与本区用水所需的地下水开采量相比较,对本区地下水资源可开采潜力进行了评价,论证了引水补源工程可有效缓解区内地下水超采问题。另外,还充分利用年地下水动态和多年地下水位动态变化等监测资料,揭示了引水补源工程对区内地下水的有效补充作用,为区内合理开发利用地下水资源提供了依据。  相似文献   

What happens after climate change adaptation projects end: A community-based approach to ex-post assessment of adaptation projects     

《Global Environmental Change》2023

Over the last decade, hundreds of climate change adaptation projects have been funded and implemented. Despite the importance of these first-generation adaptation projects for establishing funders and implementors’ “best practices,” very little is known about how early adaptation projects have endured, to what ends, and for whom. In this article, I propose a community-based methodology for ex-post assessment of climate change adaptation projects. This methodology contributes to recognitional justice by asking the individuals and collectives tasked with sustaining adaptation initiatives to define adaptation success and what criteria for success should be assessed. I apply this subjective assessment approach in 10 communities across Ecuador that participated in an internationally funded adaptation project that concluded in 2015. My analysis draws together participatory mapping, walking interviews with local leaders, participant observation, and surveys with former project participants. The results highlight that even adaptation projects that were deemed highly successful at their closure have uncertain futures. I find that the sustainability mechanisms that were envisioned by project implementors have not functioned, and communities are shouldering the burden of reviving failing adaptation interventions. These findings highlight that the current model of episodic funding for climate change adaptation projects and evaluation processes needs to be revisited to acknowledge the long-term challenges faced by communities. This analysis also calls attention to the importance of ex-post assessment for adaptation projects and the potential of subjective assessment approaches for building more ontological and epistemological pluralism in understandings of successful climate change adaptation.  相似文献   

国家自然科学基金共享航次计划固定调查断面概述          下载免费PDF全文

冷疏影  张宇  张亮  石洪华  庄志猛 《海洋与湖沼》2023,3(3):591-598

基于科考船的海洋调查是获取海洋变化第一手资料的重要方式,是孕育海洋科学原创成果的基础。2009年以来,国家自然科学基金共享航次计划实施情况表明,研究项目所需的海上调查“船时”和观测数据得以共享,但不同年份之间同一海域的站位设置及其观测方案变化较大,缺乏相对固定的调查断面研究。为进一步提升国家自然科学基金的资助成效,加强海洋过程的长期变化规律研究,自2020年起国家自然科学基金共享航次计划规划设置了34条固定调查断面,其中10余条固定断面调查要求已在随后的年度申请指南中发布。基于顶层设计思想提出的固定调查断面遵循了“突出重点、承前启后;科学引领、绩效为本;统筹兼顾、分步实施”的设置原则。其中,近海固定断面以生物多样性丰富、生产力水平较高、陆海相互作用强烈、受气候变化和人类活动双重干扰、资源环境问题突出的海域为重点,聚焦近海生态系统健康与服务功能维持、陆海相互作用的资源环境效应等关键科学问题;深远海固定断面则以对全球变化响应敏感、与我国海洋环境和气候变化关联紧密、海洋防灾减灾需求强烈的西太平洋和东印度洋海域为重点,聚焦地球系统多圈层相互作用、极端海洋环境与生命过程等关键科学问题。文章详细介...  相似文献