三峡工程蓄水对库区水质的影响分析与建议

三峡工程对生态与环境的影响是受到国内外广泛关注的焦点和热点问题之一.三峡水库135 m蓄水后1年来的水质监测结果表明:三峡水库135 m蓄水对库区干流江段未造成明显影响,但对库区部分支流局部区域的水质造成了较为明显的影响.为更好地保护三峡水库的水资源,维护库区的水质安全,应有针对性地采取措施.     

三峡水库蓄水前后气候变化分析

利用1962年 ～2017年三峡水库及其周边区域24个站点的气温和降水数据,结合Mann-Kendall非参数检验法和累积距平法分析三峡水库蓄水前后局地气候变化趋势与突变情况.结果表明,气温和降水均受影响,且影响程度具有明显的地理分布规律.蓄水对气温趋势具有稳定作用.蓄水后,气温增长幅度增大的站点主要分布在四川盆地,幅...     

三峡水库蓄水前后植被覆盖对气候的响应

为揭示三峡水库蓄水前后区域植被覆盖对气候变化的响应规律,基于SPOT NDVI和实际观测气象数据,采用偏相关系数法分析了三峡水库蓄水前后长江上游干流区间寸滩至宜昌段及外围100 km的气象因子与植被覆盖的相关性,同时对其非线性映射关系进行了研究.结果 表明:在长江上游干流区间寸滩至宜昌段及外围100 km区域内,植被覆...     

大坝蓄水初期事故分析

在蓄水初期，大坝处于一个不稳定的、复杂敏感的工作阶段。随着蓄水加荷，坝基、坝体、近坝库岸边坡等部位的运行性态不断调整变化，有可能向事故方向转化，尤其是在激烈加荷条件下，再加上设计和施工中的重要失误，这种转化很可能被触发而酿成重大事故。因此，在大坝整个生命周期中，蓄水初期是事故风险相对较大的阶段。统计了13座典型大坝蓄水初期事故，对事故原因进行了深入分析，并提出了相应的处理措施。     

Consequences of stream impoundment on fish communities in a small North American drainage

We examined impoundment associated fish community changes in the Kinkaid Creek drainage of southern Illinois by comparing collections made in 1998 and 1999 with a pre‐impoundment survey conducted in 1958. We also analyzed other historical pre‐ and post‐impoundment collections made during the past 60+ years. A dramatic change in fish community structure occurred with the pre‐impoundment community dominated by cyprinids and the post‐impoundment community now dominated by centrarchids. In addition, a 50% increase in the number of fish species known from the Kinkaid Creek drainage has occurred, with 35% of all species known from Illinois now present in the drainage. This increase in species richness coincides with the extirpation of six native species. Possible explanations for the changes in the species assemblage and increased species richness include the introduction and dispersal of non‐native fish species and habitat alteration. Finally, we contend that processes, such as habitat alteration, must be considered when analyzing the pattern of increased species richness caused by non‐native species seen in North American drainages. Copyright © 2001 John Wiley & Sons, Ltd.     

三峡水库2007年运行调度分析

2007年是三峡工程初期运行期的第一年,也是工程综合效益全面发挥的第一年。枯水期,三峡水库实施流量补偿调节,满足了通航要求;汛期,根据防总防洪调度指令实施调节,保护长江中下游的安全。     

陕西卤泊滩盐碱地综合治理的“改排为蓄 水地共处 和谐生态”模式研究

盐碱地作为一种重要的土地资源，其治理和改良意义重大。本研究以生态环境改善为目标，将盐碱地治理以“排”为核心改为以“蓄”为核心，提出并应用了“改排为蓄、水地共处、和谐生态”的综合治理模式。揭示了在蓄水条件下，水与土壤之间的动态循环压盐机理。通过科学掌握水盐运移规律,合理规划布置工程体系，采用“人工—自然”二元措施，逐步恢复区域生态，实现系统自我调节，水地资源动态平衡。通过近十年实践已取得了“经济—社会—生态”综合效益，并保证了区域“水土—生物—环境”生态系统和谐发展。     

百色水利枢纽下闸蓄水方案研究

针对百色水利枢纽由于移民搬迁滞后推迟到汛末下闸的问题,从各个方面对下闸蓄水方案进行分析研究后,决定于2005年8月26日下闸蓄水,使得2006年6月26日水库能蓄水到195 m,7月15日第一台机组顺利发电,达到了预定目标.     

Patterns of channel adjustment to impoundment of the upper River Spey,Scotland (1942–2000)

Over the last 30 years, understanding of how river channel morphology adjusts to upstream impoundment has been improved considerably with clearwater erosion close to the dam and aggradation downstream of unregulated tributary confluences being identified. In a UK context our understanding of channel response to impoundment has been based principally on analysis of a number of regulated rivers using a time–space substitution approach but the temporal pattern of channel change was not fully observed. This paper details channel change over almost six decades following impoundment of the River Spey, Scotland, primarily via the use of cartographic and aerial photographic evidence. Channel change initially involved the formation of tributary confluence bars followed by bench development and vegetation colonization and development on the benches and gravel bars. Sixty years after impoundment, the channel is still adjusting its form at distance from the dam to be in quasi‐ equilibrium with its regulated flow regime; indeed adjustment was most rapid between 1989 to 1995. This accelerated adjustment is due to the occurrence of a greater number of large and geomorphologically significant flood events in this period. Sediment supply limitation from unregulated tributaries will have stemmed the rate of narrowing and bench development prior to 1989. This spatial and temporal pattern of adjustment supports, for the most part, the model advocated by Petts (Progress in Physical Geography, 1979, Vol. 3, pp. 329–362). The wider implications of the channel change for river conservation and management are addressed. Copyright © 2003 John Wiley & Sons, Ltd.