国外河流健康评估技术

河流健康评估方法以河流生态系统状况为主线,着眼于建立河流状况变化与生物过程的关系,建立一种兼顾合理开发利用和生态保护的综合评估体系.文中简要介绍了国外河流健康评估具有代表性的技术标准,对于物理-化学评估、生物栖息地评估、水文评估、生物评估的方法和要点分别作了评述.     

河流生态功能综合评价的层次决策分析方法

介绍了基于层次决策分析的河流生态功能综合评价方法,提出了在河流水文评估、物理化学评估、生物栖息地质量评估和生物评估4个单项评估的基础上,构建以河流生态功能综合指数为目标、4个单项因子为准则、5个等级标度为决策标准的层次递阶模型,应用模型进行了河流综合评价的两种情景分析。     

河流生物栖息地的生态水文学研究

从研究对象、空间尺度和生态群体3个角度对河流生物栖息地进行分类,阐述了生态指标与水文要素间主要存在的4种关系,总结流量、流速、水位/水深、水温、水质等水流要素对河流生物的影响,归纳了目前表征河流生物栖息地的水文水力学指标和适宜性评估方法,并指出未来研究方向。     

河流保护与生态修复

分析了堤防和水坝对河流造成的负面影响:切断了河流横向和纵向的生态联系,造成水文循环短路和绝缘,河流被台阶化、节点化,从而破坏了水滨生物栖息地和水生生态系统。从河流保护概念性范围出发,分析了河流在横向、纵向、垂向以及时间维度上的水文循环和生态联系。指出恢复河流生态系统的根本思想在于推动和恢复河流在空间和时间的4维尺度上的水文循环和生态联系,避免河流水文循环短路或绝缘。总结了国内外关于河流生态修复的措施,即在河流横向营造生物栖息地、湿地、林地、深潭和浅滩等,在河流纵向补偿流量和洪水过程,重建生物栖息地和水库消落带,闸坝处建造鱼道和鱼梯等。     

河流栖息地适合度曲线与分级评价标准研究

河流栖息地具有多尺度、多等级、斑块化分布和动态变化等重要特征,常通过揭示栖息地质量的关键环境因子适合度来开展河流栖息地质量评价。本文基于国内外多种溪流型鱼类栖息地环境的流速、水深范围与偏好的流速、水深、水温研究成果,结合中国浙江省瓯江干流河段的自然环境特征和多样性的水生物学特点,选取喜缓流水型鱼类-唇䱻作为指示性物种,研究了河流栖息地关键环境因子:水深、流速、水温与水质适合度曲线,采用优、良、中、差分级评价方法,以流速、水深、水温和水质类别作为主要的判据因子,确定了河流栖息地评估的分级标准,为河流栖息地质量评价和生态适应性管理提供了科学依据。     

黄河生态水文评估指标体系的构建及案例研究

【目的】维持良好的生态水文联系是维持河流健康生命的基础，开展河流生态水文评估指标体系研究对进一步认识、量化和恢复河流系统健康状况具有重要指导意义。【方法】在总结、分析国内外相关研究成果的基础上，结合黄河生态水文特点，建立指标体系构建原则，通过因素分析提取可以表征黄河河流生态水文情势的50个指标，构建黄河生态水文评估指标体系，并将指标体系应用于黄河干流兰州断面的生态水文评估。【结果】实例研究结果表明，兰州断面的整体水文改变度为0.722，属高度改变。其中1、2、8、9月平均流量、逆转次数、高流量延时、枯季最大流量、丰季最大流量发生时间、大小洪水次数、涨水次数与延时等指标改变强烈，会对黄河兰州段的水沙关系、生物种群数量、幼苗比例、栖息地环境以及滩区、湿地、洪泛区的植被与动物种类产生较大的影响。与IHA指标体系对比，两者的评估结果基本一致。【结论】黄河生态水文评估指标体系在实际应用中可行，相对IHA指标体系更细致、更全面、更准确，可较好的反映黄河生态水文态势。     

河流栖息地健康影响因素及评价研究展望

河流栖息地是河流生态系统的重要组成部分,在河流生态系统中有着举足轻重的作用。在归纳水利工程等一系列人类活动对河流生态系统胁迫的基础上,详细阐述了栖息地及水生生物受到的主要影响。通过总结栖息地指示物种的选择、评价方法和关键指标,综合分析了指示物种及评价方法的利弊,系统梳理了国际上具有代表性栖息地评估模型的模拟方法及应用情况,并对河流栖息地健康评价的未来和发展方向进行了展望。     

基于主导生态功能分区的河流健康评价全指标体系

为建立全国河流健康评价标准的方法框架,从影响河流生态系统的生物、生境要素和人类活动要素出发,构建了包括水文特性、水质特性、河流地貌特性、生物特性和社会经济特性5方面、含36项指标的全国河流健康评价全指标体系;提出了基于主导生态功能和纬度、集水面积、距离河源的位置、河流所处地区等空间因子的两级水生态区划方法,根据河流所属水生态区构建了基于一级分区的特定河流健康评价指标体系,确定河流健康评价重点以及不同指标的权重;选择了5条河流作为示例划分水生态区,并明确了建立其河流健康评价指标体系需考虑的重点。     

基于主导生态功能分区的河流健康评价全指标体系

为建立全国河流健康评价标准的方法框架，从影响河流生态系统的生物、生境要素和人类活动要素出发，构建了包括水文特性、水质特性、河流地貌特性、生物特性和社会经济特性5方面、含36项指标的全国河流健康评价全指标体系；提出了基于主导生态功能和纬度、集水面积、距离河源的位置、河流所处地区等空间因子的两级水生态区划方法，根据河流所属水生态区构建了基于一级分区的特定河流健康评价指标体系，确定河流健康评价重点以及不同指标的权重；选择了5条河流作为示例划分水生态区，并明确了建立其河流健康评价指标体系需考虑的重点。     

河流生态状况分级系统及其应用

构建河流生态状况分级系统可为实现河流生态修复目标定量化提供技术方法。本文从自然河流生态状况的河流参照系统选择与构建出发,依据与参照系统的偏离程度,提出了河流生态状况分级系统的生态指标矩阵方法和指标赋值准则。生态指标矩阵由要素层和指标层构成,包括生物质量、水文、物理化学和河流地貌4个要素,下设10项生态指标。从河流生态系统演替的动态特征出发,阐述了河流生态状况分级系统的科学内涵,讨论了河流生态状况分级系统在确定生态修复目标、识别关键胁迫因子以及进行河流健康评估方面的应用。     

水生生物栖息地适宜性指标的模糊综合评判

针对河流水生生物栖息地数学模型PHABSIM,分析现有确定栖息地适宜性指标方法的不足之处,在此基础上给出用模糊综合评判方法,确定水生生物栖息地适宜性指标。模糊综合评判方法考虑了栖息地质量因素之间的相互作用,得到的栖息地适宜性指标准确度较高。     

鱼类栖息地环境评价指标体系初探

根据鱼类洄游、产卵和越冬等生命周期中的水环境状况、水文情势、水动力特性及地形特征等要素将影响鱼类栖息地的若干指标分成水质指标、水文学指标、水力学指标及河流地形指标。并通过分析各项指标的生态学意义,筛选出其中若干与鱼类生活、繁殖相关的评价指标。最终建立了包含目标层、要素层、特征层和指标层4个层次的鱼类栖息地环境评价指标体系,该体系以保护鱼类栖息地为目标,包含4类要素、13类特征共46项指标,可为河流栖息地评价及鱼类保护提供重要依据。     

河流健康评价的尺度转换问题初探

河流健康评价是一种兼顾合理开发利用和生态保护的综合评估体系 , 影响河流健康的主要因素、决策者的总体目标、管理行为都与河段空间尺度有关。河流健康评价首先要明确的关键问题就是尺度的问题。介绍了河流生物斑点、工程河段、景观河段和全河长 4 个尺度划分,对各尺度健康评价之间的关系进行了描述,并通过对汉江上游河段的分析与计算,说明尺度转化关系的合理性,也表明汉江上游河段河流健康程度总体是好的。     

大坝对鱼类栖息地的影响及评价方法述评

本文总结了大坝建设造成水流状态、水温、水质、底质和地形等因素的变化对鱼类栖息地造成的影响，并归纳了目前国内外对栖息地预测评价的主要方法，对每一种评价方法的特点进行了分析，最后对可采取的生态补偿措施进行了介绍。本文得到的结论为，大坝建设对鱼类的影响很大，但可以通过补偿措施加以恢复。     

山地河流生境快速评价模型与应用

从河流生境结构和功能出发,选用河流生境多样性指数、河道湿润率、生境单元质量指数,采用专家打分法确定权重系数,建立了山地河流生境快速评价指标体系及定量评价模型。选取三峡库区的典型山地河流东河进行河流生境质量定量评价。结果表明该河流生境质量从库尾以上河段起向下游逐步下降,在引水坝以下河段降至最低,其后呈逐渐恢复的态势。坝下河流生境主要受到河流减水影响;坝上河段河流生境主要受泥沙淤积影响。该评价结果能较直观地反映水电工程影响下山地河流生境状况,以及导致河流生境质量衰退的原因。     

Development of transient habitat modeling for stream Macrozoobenthos

In addition to the hydromorphological pressure on the ecological conditions of free-flowing river courses, increasing water temperature is affecting the water bodies, particularly by changing freshwater community compositions. The low discharge of numerous European rivers in the dry and hot hydrological year 2022 proves this relevance. Therefore, ecological assessment tools such as habitat modeling should take these factors into account when assessing the quantity and quality of habitats. In this paper, the habitat modeling tool “Transient River Habitat Modeling for Macrozoobenthos” (TRiMM) is improved by incorporating a fuzzy logic approach and adding water temperature to the set of parameters determining habitat suitability for macrozoobenthos. Habitat-relevant parameters, including hydromorphological factors (depth, velocity, mineral and organic substrate) and a water quality factor (temperature), are combined in the habitat model so that it can more broadly characterize river physical conditions and their interactions with biological indicators. Habitat modeling employed the mentioned parameters to simulate suitability for the macrozoobenthos in a small river in central Saxony, Germany. Due to its deteriorated condition, this river was selected as a representative for thousands of kilometers of small rivers across the region, which have been restored. The model simulated the status quo of river conditions from spring to summer for three macrozoobenthos species (Ancylus fluviatilis, Ephemera danica and Gammarus fossarum). The results showed that the natural flow resulted in dynamic habitat suitability both spatially and temporally, which differs for each species. Remarkably, the five-parameter model (depth, velocity, temperature, mineral, and organic substrate) generally performed better compared to a similar model without temperature.     

The impacts of cattle access points on deposited sediment levels in headwater streams in Ireland

Cattle access to streams has been linked globally with degradation of stream water quality, driven largely by bank erosion and resultant instream, fine sediment deposition. The majority of evidence on such effects is however based in arid and semiarid regions of the United States and Australia, with few studies relating to cool temperate climates such as Northwest Europe. In this study, “Quorer” resuspendable sediment samples were taken from riffle geomorphic units upstream (control) and at two points downstream (pressure and recovery) of cattle access points in headwater streams in agricultural catchments in Ireland to assess levels of deposited stream sediment. Samples were taken in April/May (2016) prior to the grazing season and in October (2016) at the end of the grazing season. Sites in good‐high ecological status catchments and less than good ecological status catchments were included in the study. Higher levels of sediment were found downstream of cattle access points in both good‐high status and less than good status catchments; however, the impacts of access points were spatially confined to, in most cases, the area immediately downstream of the point of access. There was a strong correlation between deposited sediment mass and organic matter (OM) mass, with levels of OM increasing linearly with deposited sediment mass. Levels of measured sediment were negatively correlated with riparian habitat health (measured using a qualitative habitat assessment). The results of this study highlight the need for measures to prevent cattle access to headwater streams where access points can be many in order to manage local habitat quality and downstream water quality issues.     

山地河流生境快速评价模型与应用

从河流生境结构和功能出发，选用河流生境多样性指数、河道湿润率、生境单元质量指数，采用专家打分法确定权重系数，建立了山地河流生境快速评价指标体系及定量评价模型。选取三峡库区腹心区域的典型山地河流东河进行河流生境质量定量评价。结果表明河流生境质量从库尾以上河段起逐步下降，在引水坝以下河段降至最低，其后呈逐渐回复的态势。坝下河流生境主要受到河流减水影响；坝上河段河流生境主要受泥沙淤积影响。评价结果能较直观地反映水电工程影响下山地河流生境状况，以及导致河流生境质量衰退的原因。     

History and review of the habitat suitability criteria curve in applied aquatic ecology

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.