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针对传统河流物理栖息地模型计算范围不足,提出一种新的河流鱼类栖息地生态适宜度指数计算模型,并通过鲢鱼实地调查试验,对模型计算结果进行验证。结果表明:新模型可综合考虑河段区间汇水对鲢鱼生境的综合影响,模拟结果与实地调查结果吻合度较高。研究成果对水库放水对河道鱼类生态环境影响评估具有重要的参考价值。 相似文献
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基于协调发展度的河流健康评价方法研究 总被引:2,自引:0,他引:2
为评价河流系统的健康和协调发展状况,首先,从影响河流生态完整性要素和社会服务要素的角度出发,构建了包括水文资源、物理结构、水质、生物和社会服务功能等多个准则层的河流健康评价指标体系的统一框架;然后,借鉴社会经济与环境的协调发展度理念,建立了河流系统的协调发展度评价模型,并探索性地提出了基于河流健康管理的协调发展度等级标准;最后,以滦河为研究对象,对2011年滦河健康状态与协调发展状况进行了实证研究。结果表明,协调发展度模型既能评价河流系统的健康程度,又能衡量河流自然属性与社会属性的协调发展状况。 相似文献
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温榆河生态河流健康评价研究 总被引:6,自引:0,他引:6
针对传统的河道治理工程只侧重功利价值而导致生态环境遭到破坏的问题,以温榆河为例,研究生态河流健康评价指标体系的构建及评价方法.本文在综合国内外河流健康状况的评价方法及各项表征指标的基础上,构建基于多指标综合评价方法的河流健康状况评价的指标体系并确定了评价标准;设计河流健康评价指标重要度比较调查表确定了评价权重-根据隶属度的计算方法,确定定量指标的隶属度;设计定性指标等级评价表,邀请专家根据定性指标评价等级标准,对研究区域河流健康状况进行打分,采用百分制统计法统计专家意见计算定性指标的隶属度矩阵;建立河流健康评价的模糊综合评价模型,对温榆河河流健康状况进行了评价.评价结果,温榆河河流健康状况为亚健康,指出了温榆河生态健康的薄弱环节,有针对性地提出改进措施和建议,促进河流生态系统向良性方向发展. 相似文献
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随着人口的急剧增长和工农业生产的蓬勃发展,河流生态系统的健康受到严重威胁,人类开始对各种自然因素和人为因素对河流健康所造成的影响给予高度重视,并期待能拟定更合适的理论体系对这些影响进行科学评价。通过文献综述,介绍了河流健康的内涵,针对河流健康发展所要解决的主要问题,分析了目前河流健康的评价标准、评价方法、评价指标体系的优缺点。并根据目前河流健康评价研究领域的状况,指出了在评价过程中所存在的问题,并展望河流健康评价工作在未来发展的趋势。 相似文献
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长江流域水系划分与河流分级初步研究 总被引:1,自引:0,他引:1
将推荐的水系划分与河流分级Horton法相结合,通过合理选取最小河流(流域)单元、科学制作河流树状图表,初步研究了长江流域(不含太湖水系)的河流分级。研究结果显示:①推荐将长江水系划分为干流水系与雅砻江、岷江、嘉陵江、乌江、洞庭湖、汉江、鄱阳湖、太湖8个支流水系;② 581条河流基本特性资料的收集、整理与分析表明长江流域河流的河长与流域面积约为0.5次方关系,选取流域面积不小于2 000 km2或河长不小于100 km的河流为最小河流(流域)单元,确定长江流域(不含太湖水系)河流总数为374条;③以岷江水系为例,精心制作了长江流域各水系的河流树状图表,树状图显示了河流隶属关系、分级数、河长、流域面积等特性;④长江流域(不含太湖水系)最高河流分级数为6级。按河流统计:6级1条(0.3%),5级3条(0.8%),4级6条(1.6%),3级14条(3.7%),2级71条(19.0%),1级279条(74.6%);按水系统计:岷江、嘉陵江、鄱阳湖为5级,干流、雅砻江、洞庭湖、汉江为4级,乌江为3级。 相似文献
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河流生态系统健康评价关键指标研究 总被引:1,自引:0,他引:1
在充分研究和详细总结国内外河流生态系统健康指标及其评价研究成果基础上,通过对河流生态系统结构、功能以及生态系统的物质和能量流等方面的进一步识别,从河流生态系统活力、恢复力、组织、生态系统服务功能的维持、管理选择、外部输入减少、对邻近系统的影响及人类健康影响8个方面归纳总结了河流生态系统健康评价的理论、方法和标准,同时考虑河流生态系统强大的生态服务功能,在进行河流系统健康评价时增加了生态服务功能指标。通过系统分析河流生态系统健康指数系统,筛选了河流生态系统健康评价关键指标,提出了河流生态系统健康评价关键指标分级评价标准,并对河流生态系统健康总体评价进行了探讨,为河流生态系统健康评价提供了参考依据。 相似文献
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北方地区由于缺水干旱、城市化进程发展和人为活动等影响导致河流生境退化严重,现有评价体系和方法不能很好地反映河流生境状况,基于此,构建了包括河流形态结构、水质水量、河岸带状况、景观环境、水生生物5个方面共13项指标的北方河流生境质量评价指标体系,确定了各指标的等级划分及生境质量综合指数计算方法。结合北京市延庆区妫水河生境调查结果,对流域内选取的妫水河干流及3条支流按照河流河段尺度分为缓坡型、山区型和城区型河段,并利用构建的评价体系和方法开展具体评价。结果表明:(1)研究区域13个样点的河流生境质量状况差异显著,约46.2%的样点河流生境质量处于好等级,约15.4%的样点为较好等级,约7.7%的样点为一般等级,约23.1%样点为较差等级,约7.7%的样点为最差等级。(2)缓坡型河段的生境质量明显优于山区型河段和城区型河段,其生境等级为"好",山区型和城区型河段的生境等级均为"较差",表明河流水量和人类负面干扰对河流生境影响较大。(3)该评价指标体系适合北方缺水干旱的特殊生境状况,其评价结果较为直观的反映了河流生境现状,兼备科学性和可操作性。 相似文献
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Abraham Bij De Vaate Alexander G. Klink Marianne Greijdanus‐Klaas Luc H. Jans Johan Oosterbaan Frank Kok 《河流研究与利用》2007,23(2):171-183
River engineering in the Rhine delta and water pollution have been major threats for the ecological functioning of the river in The Netherlands. To mitigate effects of river engineering, secondary channel construction in the forelands along the existing distributaries is considered to be an important measure for river restoration. These areas are the remnants of the former Rhine floodplain and the only area where habitat restoration is possible due to the river functions assigned. Secondary channel construction in the area called ‘Gamerensche Waarden’ was taken as an example to show effects of habitat restoration on the macroinvertebrate fauna. Totally 322 macroinvertebrate taxa were found during the monitoring period. During the first 3 years species richness in the area increased rapidly due to colonization processes in the channels following habitat development. After that period total number of taxa found in the channels stabilized at around 170. A clear positive relationship was demonstrated between habitat quality and species richness. Furthermore, the density of exotic species in the secondary channels was less than in the groyne fields of the main channel. The relatively low number of taxa in polluted habitats could be explained by the presence of the PCB 28 congener. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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针对河流健康评价中诸多评价方法在指标权重确定方面存在困难的问题,应用组合赋权模糊评价方法,实现河流健康等级评价。该方法将主观赋权和客观赋权相结合来确定指标权重,并应用模糊综合评判方法进行河流健康评价,克服了单纯主观赋权的人为干扰,使评价结果更加客观真实。以滦河下游唐山地区8个河段为计算实例,构建评价指标体系和评价标准,得到所研究区段河流健康状况均为亚健康偏于不健康状况,与改进主成分分析评价方法进行比较,结果基本一致,证明了该方法的合理性。 相似文献
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陈兴茹 《中国水利水电科学研究院学报》2016,(6):443-447
近年来后评估越来越受到河流生态修复领域的重视,成为评判河流生态修复措施成功与否的关键,其中河流生态修复效益评估作为河流整治后评估的重要组成部分,与投资方及受益群体的关系最为密切。本文以目前国内外正在大范围开展的河流生态修复工作为着眼点,系统总结了国内外河流生态修复的经济效益、生态环境效益和社会效益及其计算方法,指明了现有研究存在的问题及今后应注重开展的研究方向,为相关从业人员了解该领域的研究动向提供参考。 相似文献
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弯曲河道立堵截流龙口水力特性分析 总被引:1,自引:0,他引:1
弯曲河道中截流水流运动规律极为复杂,弯道边界形态和立堵截流布置方式的不同对截流难度均有很大的影响,对弯道中立堵截流龙口水力特性进行分析,有助于了解复杂的水流流态并选择合适的截流方案。本文考虑弯曲河道截流的主要影响因素,以施工水力学为基础,建立弯道截流龙口水流流态和堤头局部水力特性的计算模型,分析弯道相对河宽、弯道弯角和龙口位置对水深和流速变化的影响。分析结果表明弯道截流龙口流速变化有显著的时变差异和位变差异,并给出了龙口相对水深和堤头局部流速随弯道形态的变化关系。最后结合大渡河丹巴水电站河湾上截流的工程案例分析比较,验证了计算模型的可行性和分析结果的适用性,为河湾中截流方案及其截流施工布置型式的选择提供了理论依据。 相似文献
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Loss of habitat complexity through river channelization can have adverse affects on riverine fauna and flora through reductions in abundance and diversity of species. Habitat enhancement schemes are used to improve the physical and biological heterogeneity of riverine habitats. Between 1996 and 1997 the Environment Agency undertook a habitat enhancement scheme on the Huntspill River, Somerset, England to improve conditions for coarse (non‐salmonid) fishes. The scheme involved reducing bank gradients and the construction of off‐channel bays in parts of the channel, all of which were planted with willow (Salix sp.) and common reed (Phragmites australis). The effectiveness of the enhancement scheme was investigated by comparing 0‐group fish assemblages in manipulated and unmanipulated sites. Abundance and diversity of 0‐group fishes was significantly higher in manipulated habitats. There was no significant difference detected in the effects of the different types of enhancement measure used. The significance of microhabitats produced by habitat enhancement schemes is discussed with respect to spawning, nursery and refuge sites for 0‐group coarse fish assemblages. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Hydraulic microhabitat assessment is a category of environmental flow tools (e.g., Physical Habitat Simulation system and other methodologically similar software) that, at its core, uses habitat suitability criteria (HSC) to link values of point hydraulic variables (usually depth, velocity, and substrate/cover) to habitat values for target life stages. Although this assessment tool has been used worldwide for decades, the history of the HSC curve is relatively unknown because the foundational information is predominantly contained in obscure and often unpublished reports. We review the history of the HSC concept in applied aquatic ecology to clarify its scientific pedigree, ensure its proper use, and build a foundation for future research. We begin the review with the formative decades of the 1950's through the 1970's, when consumptive‐based western USA water law conflicted with conservation traditions and natural resource management objectives, although water allocation issues date back at least to the 19th century. By analysing the history of the HSC concept, we aim to establish the biological, hydrologic, and geomorphological conditions that must be met for the HSC concept to be successfully employed. In spite of its documented assumptions and limitations, the HSC concept will likely continue to be a useful tool to help address water resources allocation issues in defined hydrologic and geomorphic settings. We conclude that HSC‐based methodologies should be considered as one of several environmental flow approaches involved in sustainable water resources management. 相似文献
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During floodbank raising work as part of a major capital flood defence scheme on the River Torne between 1985 and 1990, selected reaches of the main trapezoidal channel were enhanced. By winning spoil from the channel margins and from borrow pits in the floodplain, a more varied marginal zone was created which maximised the potential habitat for wetland plant communities and their associated fauna. Enhancement comprised bank re‐profiling to create narrow wetland shelves (berms), shallow bays, channel margins of varying shape and depth and linear still ponds from the borrow pits. The 1990 planting programme comprised 11 macrophyte species and a total of 7740 individual plants. This paper reports on an initial study to evaluate the marginal habitat enhancements on the River Torne 5 years after completion of the project. Lack of pre‐scheme data necessitated a space‐time substitution; enhanced river margins were compared with neighbouring reaches that had undergone conventional floodbank repair and remained as trapezoidal channel sections planted with a standard, low maintenance seed mix. Marginal vegetation was surveyed and supported by measurements of the physical habitat at 10 enhanced and 10 conventionally‐engineered reaches. The macrophyte surveys and the results from the cluster analysis and polar ordination indicate that enhanced and conventionally‐engineered reaches are floristically distinct and that the enhanced reaches have a more varied macrophyte community. The results from the Mann–Whitney U‐tests show that enhanced reaches have significantly higher values of wetland species diversity and equitability, percentage of wetland species, bank width and soil moisture and significantly lower bank angles. However, the correlation and linear regression analyses did not show any strong associations between the physical habitat and plant parameters. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献