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我国水土保持小流域综合治理的回顾与展望 总被引:35,自引:0,他引:35
近30年来,小流域综合治理在理论、实践、技术、体制、机制等方面不断创新和发展,现已成为我国水土保持生态建设的一条重要技术路线,为改善我国水土流失地区生态与环境、发展农村经济、促进经济社会可持续发展做出了显著的贡献.小流域综合治理要以水土资源的可持续利用和生态与环境的可持续维护为目标,进一步满足经济社会发展多样化的需求,大力推进规模化治理,创新治理开发机制,把人工治理与发挥大自然的自我生态修复能力结合起来,实现水土保持工作在更高层次上的推进和加强. 相似文献
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Geomorphic diversity as a river management tool and its application to the Ganga River,India 总被引:1,自引:0,他引:1 下载免费PDF全文
Understanding of geomorphic processes and the determination of geomorphic diversity in catchments are prerequisites for the sustainable rehabilitation of river systems and for reach‐scale assessment of river health. The Ganga River system in India is a large, complex system consisting of several long tributaries, some >1,000 km, originating from 2 distinct hinterlands—the Himalaya to the north and the cratons to the south. Traversing through a diverse climatic regime across the Plain and through precipitation zones ranging from 600 mm/year near Delhi to 1,200 mm/year in the eastern plains, the Ganga River system has formed very diverse landform assemblages in 3 major geomorphic domains. We have recognized 10 different river classes for the trunk river from Gangotri (source) to Farakka (upstream of its confluence with the Brahmaputra) based on (a) landscape setting, (b) channel and active floodplain properties, and (c) channel planform parameters. The mountainous stretch is characterized by steep valleys and bedrock channels and is dominated by large‐scale sediment production and transport through hill slope processes. The alluvial part of the river is characterized by 8 different river classes of varying reach lengths (60–300 km) many of which show sharp transitions in landscape setting. We have highlighted the application of this approach for the assessment of habitat suitability, environmental flows, and flood risk all of which have been significantly modified during the last few decades due to large‐scale anthropogenic disturbances. We suggest that the diversity embedded in this geomorphic framework can be useful for developing a sustainable river management programme to “work with” the contemporary character and behaviour of rivers. 相似文献
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David Dudgeon 《河流研究与利用》1995,11(1):35-54
Southern China—i.e. China south of the Chang Jiang (Yangtze River)—has a monsoon climate with pronounced wet and dry seasons and consequent effects on river discharge. There is considerable inter-year variation in the duration and intensity of the monsoon, and the region experiences frequent floods and droughts which cause considerable human misery. The importance of floods as an incentive for river regulation is apparent from the fact that 10% of China's area, inhabited by 65% of the population and responsible for 70% of the agricultural and industrial output, is below the flood level of major rivers. Irrigation and hydroelectric power are additional benefits to be derived from river regulation. China has a 4000 year history of river regulation, but most of the changes that have been made to riverine environments have not taken account of the ecological consequences. This review considers the ecological implications of planned or existing schemes for the regulation of southern Chinese rivers. Particular attention is paid to the Chang Jiang and Zhujiang (Pearl River) which, by volume of discharge, are the two largest rivers in China. Large-scale water-transfer projects and the planned construction of the biggest dam in the world (the Three Gorges High Dam) on the Chang Jiang have the potential to affect fisheries stocks and endangered fish species, to alter inundation patterns in wetlands of international conservation significance and may contribute to the extinction of the endemic and highly endangered Chinese alligator (Alligator sinensis) and Chinese river dolphin (Lipotes vexillifer). In addition, deforestation and soil erosion in the Chang Jiang basin have given rise to siltation and degradation of floodplain habitats. In the Zhujiang, dam construction has caused reductions in fisheries stocks but here, as elsewhere in China, the ecologically damaging consequences of river regulation are exacerbated by overfishing and increasing pollution of rivers by sewage, pesticides and industrial wastes. 相似文献
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灌区工程管理的日常维护与养护工作是保证工程正常运行及效益发挥的基础.在灌区工程日常管养工作中潦河灌区管理局根据自身实际需求,进行试点推进管养承包管理模式,在实践过程中取得了一些经验与成效,同时指出在实际操作中应该注意的问题. 相似文献
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国外流域综合管理模式对我国河湖管理模式的借鉴 总被引:2,自引:0,他引:2
针对我国现阶段河湖管理采用流域管理和行政管理相结合的模式,管理实践中存在着流域管理机构与主导政府机构权责不清、公众有效参与不足的问题,以美国五大湖流域、英国东南流域、澳大利亚墨累-达令流域、法国卢瓦尔-布列塔尼流域等为例,对美国、英国、澳大利亚、法国、德国5个主要西方发达国家的各自最有特色的河湖管理模式中流域管理机构、主导政府机构、公众参与、流域管理特点进行了分析及归纳总结,以期对我国最近提出的流域综合管理提供参考。 相似文献
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用自然修复理念指导长江流域水土保持工作 总被引:1,自引:2,他引:1
长江流域气候温和湿润,大自然自我修复能力很强,自然修复理念对做好新时期的水土保持工作具有十分重要的指导意义.自然修复形成的生态系统比人工治理建立的防治体系保持水土的效果更好,在气候温和湿润的地区更是如此.从"人工治理一遍"到"充分依靠自然修复能力"是水土保持工作思路的重大转变,自然修复理念将极大地推动水土保持理论、技术线路和实践全面创新.提出了实践自然修复理念需要重点把握和解决好以下几个问题:①强化统筹协调;②坚持因地制宜;③改进管理方式;④准确把握定位. 相似文献
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The French Broad River originates in North Carolina, flows west into Tennessee and at its confluence with the Holston River forms the Tennessee River. Douglas Dam, located on the French Broad River 52 km above its mouth, is operated primarily for peaking hydroelectric power and flood control. Prior to completion of the dam in 1943, the lower French Broad River contained about 53 species of freshwater mussels and 100 species of fish. By 1977, the fauna in the 52‐km‐long tailwater was reduced to 12 species of mussels and 42 native species of fish. Improvements in tailwater conditions occurred following initiation of minimum flows in 1987, and consistent reaeration of discharge in 1993. From 1988 to 2002, we sampled three sites (4, 28, and 39 km downstream of the dam) to monitor the fish assemblage. Each year since 1988, we have collected one or more additional species, indicating continued immigration. We collected 82 native and 9 exotic species of fish overall, but the maximum of 67 species in 1 year suggests that some species reside in the tailwater at low densities or all immigrants may not successfully colonize the tailwater. There is limited potential for most extirpated species of mussels to naturally recolonize the tailwater because source populations are isolated. Consequently, 19 754 adult mussels of 19 species were introduced between 1997 and 2000. Survival of translocated mussels has been high, and successful reproduction of at least one translocated species has occurred. Additionally, four mussel species are naturally colonizing the tailwater. Colonization and recruitment of additional mussel species is expected as populations of their host fishes increase. We believe that the improved conditions of the tailwater may allow for the re‐establishment of sustaining populations of 30 mussel species of historic occurrence, but the continued operation of Douglas Dam as a peaking hydroelectric project will reduce the probability of successfully reintroducing some species. Published in 2006 by John Wiley & Sons, Ltd. 相似文献
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This paper examines the feasibility of using multivariate statistics to model fish species distribution and habitat requirements for intermittent streams in semi‐arid regions, many of which are coming under increasing pressure from water resource development schemes. The assessment was based on the geographical distribution of six endemic fish species in the Guadiana river, a semi‐arid river system in southern Iberia. Their presence was related to 20 environmental variables linked to climate, geomorphology, riparian vegetation and location in the drainage basin. These variables were collected in the field or from topographical maps to evaluate habitat suitability and to predict the presence of the species according to season. Multivariate logistic regression in a geographic information system (GIS) environment was performed to identify regions with high probability of occurrence for each species. The variables that best explained the occurrence of the species were the sample location in the drainage basin, the geomorphology and the riparian vegetation. The models presented have a high predictive power and can be used in monitoring and predicting temporal changes caused by human activities. This modelling approach can be used to predict the areas that need to be conserved to protect or rehabilitate the endangered species. Armed with this information, managers can formulate conservation measures to prevent further degradation of the stocks and possibly enhance the populations. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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在简要介绍城市河流系统治理策略的基础上,详细论述其在鹅颈水生态修复中的应用。鹅颈水治理以流域为空间单位,准确把握河流主要问题,综合考量水资源、水安全、水环境、水生态、水文化,坚持工程和非工程措施并重,分阶段逐步实现洪水风险管理、外源污染控制、河流水质修复、河流生态系统恢复的目标。结果表明,鹅颈水目前已基本消除黑臭,水质逐渐提升至国家地表水Ⅳ类水标准。提出进一步加强河流生态系统恢复、优化管理制度、逐步建立全过程和全指标生态监测评估体系、实施弹性管理等鹅颈水系统治理措施。 相似文献
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基于长江河道南京段运行管理的各项技术指标资料,构建了IAHP-Delphi-FCA模型对南京长江河道工程运行管理进行评价。运用改进的层次分析法计算各指标相对于上层指标的相对权重;邀请若干专家对各单项指标进行评分,确立评分标准与评分分数表;最后根据模糊综合评判模型进行模糊运算,得到综合评价结果。通过河道工程运行管理进行评价,可以总结河道工程运行管理过程中存在的问题,为后续工程防洪能力的提升和工程决策提供科学依据。 相似文献
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《Journal of Great Lakes research》2023,49(4):876-887
Biological invasions can produce severe ecological impacts at both large spatial scales between distantly related species and also smaller spatial scales between conspecifics. We investigated here a potential intraspecific invasion within Lake Michigan and adjacent waters. Banded killifish (Fundulus diaphanus) experienced population increases and spread into novel habitats over recent decades in this region, but managers and policy makers were uncertain if these fish were native western banded killifish (F. d. menona) or instead an invasion by non-native eastern banded killifish (F. d. diaphanus). We applied mitochondrial DNA (mtDNA) barcoding and population genetic analyses to investigate the identity of these fish. We found that new banded killifish populations were the eastern subspecies, including mtDNA haplotypes from the remote mid-Atlantic region, suggesting some introductions from anthropogenic pathways (e.g., live bait trade) rather than only spread from connected, downstream waters (e.g., Lake Erie). Further, population genetic analyses identified eastern banded killifish in our focal region as having low genetic diversity relative to their native range, and relative to western banded killifish populations. Lastly, we found non-native eastern banded killifish were associated with Lake Michigan and connected waters, rather than isolated kettle lakes, and primarily occurred at clearer sites potentially affected by dreissenid mussel invasions. More research is needed on the causes and consequences of eastern banded killifish invasions in Lake Michigan and adjacent waters, including an emphasis on their risk to the conservation of western banded killifish. 相似文献
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广西河道管理存在的问题与建议 总被引:3,自引:1,他引:3
随着经济建设的发展,河道违章建设项目有递增的趋势,已成为河道管理,防洪工作的毒瘤。为确保河道管理,防洪工作的顺利开展,建立一个稳定的经济发展环境,各级河道主管部门必须提高认识,依法加强河道管理工作。 相似文献
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Reliable estimates of abundance are needed to assess consequences of proposed habitat restoration and enhancement projects on freshwater mussels in the Upper Mississippi River (UMR). Although there is general guidance on sampling techniques for population assessment of freshwater mussels, the actual performance of sampling designs can depend critically on the population density and spatial distribution at the project site. To evaluate various sampling designs, we simulated sampling of populations, which varied in density and degree of spatial clustering. Because of logistics and costs of large river sampling and spatial clustering of freshwater mussels, we focused on adaptive and non‐adaptive versions of single and two‐stage sampling. The candidate designs performed similarly in terms of precision (CV) and probability of species detection for fixed sample size. Both CV and species detection were determined largely by density, spatial distribution and sample size. However, designs did differ in the rate that occupied quadrats were encountered. Occupied units had a higher probability of selection using adaptive designs than conventional designs. We used two measures of cost: sample size (i.e. number of quadrats) and distance travelled between the quadrats. Adaptive and two‐stage designs tended to reduce distance between sampling units, and thus performed better when distance travelled was considered. Based on the comparisons, we provide general recommendations on the sampling designs for the freshwater mussels in the UMR, and presumably other large rivers. Published in 2009 by John Wiley & Sons, Ltd. 相似文献
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An Evaluation of Streamflow Augmentation as a Short‐Term Freshwater Mussel Conservation Strategy 下载免费PDF全文
Recurrent and prolonged droughts, coupled with increased water resource demand, threaten freshwater mussel populations through stream drying and water quality degradation. Augmentation of stream discharge was proposed as a short‐term strategy to maintain adequate streamflows and water quality in reaches with important freshwater mussel populations during exceptionally low flow periods. We investigated the effects of water augmentation on seven freshwater mussel species in a small creek between 2011 and 2014. Using capture‐mark‐recapture methods, we monitored mussel populations in a control reach upstream of an augmentation outlet and two reaches immediately downstream of an augmentation outlet. Water quality measurements during our study indicated that augmentation improved water temperature and dissolved oxygen conditions during low flow periods. For all mussel species, apparent survival was positively related to minimum streamflows and declined precipitously as streamflows decreased. However, mean apparent survival between sampling occasions was high among all species but did not differ among treatment units, suggesting that flow augmentation rates in this study were insufficient for abating the effects of basin‐wide reductions in streamflow. Temporary emigration differed among study reaches but did not support hypothesized relationships because it increased with stream stage and was highest in an augmented reach. This suggests that streamflows did not drop below thresholds, which invoked burrowing as a response to decreased streamflows. Streamflow augmentation may be a viable short‐term mussel conservation strategy in small streams but will likely require higher augmentation volume capacity than evaluated during our study. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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