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关键词： REPUBLIC-OF-CHINA   POYANG LAKE   JAPONICUM INFECTION   SICHUAN PROVINCE   INTERVENTION   PRAZIQUANTEL   RESISTANCE   DISEASES   STRATEGY   HEALTH  

摘要： Background: Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes. Methodology/Principal Findings: We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission modes below the TGD across four provinces (Hunan, Jiangxi, Hubei and Anhui) to determine whether there was any immediate impact of the TGD on schistosomiasis transmission. Eight sentinel villages were selected to represent both province and transmission mode. The primary end point measured was human incidence. Here we present the results of this five-year longitudinal cohort study. Results showed that the incidence of human S. japonicum infection declined considerably within individual villages and overall mode over the course of the study. This is also reflected in the yearly odds ratios (adjusted) for infection risk that showed significant (P< 0.01) downward trends in all modes over the follow-up period. Conclusions/Significance: The decrease in human S. japonicum incidence observed across all transmission modes in this study can probably be attributed to the annual human and bovine PZQ chemotherapy. If an increase in schistosome transmission had occurred as a result of the TGD, it would be of negligible size compared to the treatment induced decline seen here. It appears therefore that there has been virtually no immediate impact of the TGD on schistosomiasis transmission downstream of the dam.

关键词： 三峡坝区   巨无霸   环保   漂浮物   三峡大坝   垃圾场   船   葛洲坝  

摘要： 长江六千余公里，沿江居民数亿。每年汛期漂浮物顺流而下，形成绵延上百公里、种类繁多、愈滚愈大的垃圾洪流。三峡大坝建成前，下游葛洲坝每年遭遇漂浮物围困，在坝前形成一个污臭杂乱、缠绞密实，面积约80个足球场的巨大漂浮垃圾场。其上可“行车走人”。采用传统的人海战术，手捞肩扛清理量每天仅数千立方米，杯水车薪，无法应对。漂浮物堵塞发电机进水口，

关键词： 国家级自然保护区   三峡大坝   金融危机   长江中上游地区   超级银行   长江上游   后续效应   金融业   技术手段   鱼类保护  

摘要： 去年,长江中上游地区经历了一个难熬的夏天。干旱和酷热再度激起了关于三峡大坝及其后续效应的争议。而在欧洲和美国,关于大银行在金融危机中扮演的角色的讨论,也进行得如火如荼。超级大坝和超级银行,都是各自领域中的巨无霸。

关键词： 武汉植物园   三峡大坝   生态植被   混凝土   研发   大型水利水电工程   专家   中国科学院  

摘要： 三峡大坝作为备受世界瞩目的大型水利水电工程，其生态保护与水保建设一直为世人关注。13日，记者从中国科学院武汉植物园了解到，由该园研发的混凝土“生态植被块”经过近两年试验验证，不仅可有效实现护坡固土的基本功能，还为三峡坝区近4公里消落带营造出一道靓丽的绿色景观线。

关键词： 水电机组   三峡大坝   金沙江   船运   转轮   世界   向家坝水电站   重件码头  

摘要： 3月30日上午，享有“世界单机容量最大水电机组”之称的向家坝80万千瓦机组转轮在三峡大坝重件码头装载上船。未来10天内，这个“巨无霸”将滑长江逆江而上，航行约700公里到达位于金沙江的向家坝水电站。

关键词： 三峡大坝管理区   植被现状   生态保护与修复   绿地系统优化建设  

摘要： 三峡工程是当今世界上最大的水利枢纽工程,在建设过程中不可避免的对工程所在地的陆生环境以及水生生物环境带来影响。文章针对三峡坝区的现实状况,提出了加快三峡坝区生态环境修复建设,促进区域可持续发展的主要对策。

关键词： 水电机组   三峡大坝   金沙江   船运   转轮   世界   向家坝水电站   重件码头  

摘要： 2012年3月30日上午，享有“世界单机容量最大水电机组”之称的向家坝80万kW机组转轮在三峡大坝重件码头装载上船，运往位于金沙江的向家坝水电站。

关键词： 混凝土施工   表面裂缝   温度   高速公路施工   现代工程   三峡大坝   桥梁建设   住宅施工  

摘要： 混凝土施工在现代工程建设中占有重要地位。大到三峡大坝、大型桥梁建设,小到普通住宅施工,尤其在现代化高速公路施工中,都离不开混凝土。而在混凝土施工中,表面裂缝的存在较为普遍。究其原因,我们发现：温度的影响是混凝土产生裂缝的主要原因之一。

关键词： 种群遗传多样性   长江上游   黑斑病   人口观   DNA分析   微卫星   三峡大坝   显示  

摘要： Lepturichthys fimbriata (Günther) is one of the benthic and rock-attached fish species that is typically found in torrential flows of the upper reaches of the Yangtze River in China. Several dams in the Yangtze River (the Ertan Dam, the Three Gorges Dam, the Gezhouba Dam, the Xiluodu Dam and the Xiangjiaba Dam (the latter two dams are under construction)) may have significant effects on the habitat and spawning behaviors of L. fimbriata, and could ultimately threaten the survival of this fish. We studied the population genetic diversity of L. fimbriata samples collected at three sites within the Yangtze River and one of its tributaries, the Yalong River. Genetic diversity patterns were determined by analyzing genetic data from 14 polymorphic microsatellite loci isolated in Jinshaia sinensis (Sauvage et Dabry). A high genetic diversity among these L. fimbriata local populations was indicat- ed by the number of microsatellite alleles (A) and the expected heterozygosity. No reductions of genetic diversity in any L. fimbriata population were observed. However, significant population differentiations were observed among three local populations by pairwise comparisons (P<0.001). We deduced that L. fimbriata local populations were not small ones. In addition, the habitat behaviors of rock-attachment and possible residence of L. fimbriata could account for the genetic differences found in local populations.

关键词： 水利水电   工程管理   三峡大坝   措施  

摘要： 随着经济的发展,人民生活水平日益提高,对国家基本工程建设也越来越了解。水利水电工程是国民经济和社会发展的基础产业,其发挥的功能对人民的日常生活起了非常重要的作用。国家也越来越重视水利工程的管理工作,本文通过对水利水电工程管理的现状分析,探讨其相关解决方案。