基于RS 的河流物理结构完整性评价的方法研究——以第二松花江为例

以第二松花江子流域为研究区,利用RS和GIS技术,基于水利部《河流健康评估指标、标准与方法 V1.0》并加以改进,将整个河漫滩纳入河流物理结构健康评价的范围,科学地选取相应评价指标,建立520个物理结构评价基本单元,形成基于RS物理结构评价方法。研究结果表明:14个采样点,基于RS物理结构评价结果在0.54~0.80之间,地面实测评价结果在0.55~0.79之间,两种方法评价结果的数值差异均在0.2之内,其差异均在一个健康状态等级之内,且与研究区河岸带物理结构健康状态的总体趋势吻合。     

辽河干流沙化特征定量评价及驱动机制综合分析

基于粗糙集理论按照草地、农田、林地、湿地等辽河干流流域主要土地利用类型,构建了不同地类以生物、土壤、气候为指标层的沙化的评价指标体系,对辽河干流沙化特征进行定量评价和空间区划,并对其驱动机制进行综合分析.研究成果对于辽河干流生态保护具有重要参考价值.     

辽河流域健康评价指标体系初探

辽河流域生态脆弱,河流污染严重.本文基于辽河现状,从辽河流域、河流廊道、栖息地3个尺度,确定评价指标体系,采用熵权法和集对分析不确定性理论,对辽河流域健康指标进行评价分析确定,为辽河水生态保护和修复提供决策依据.     

辽河流域水资源承载能力研究

本文根据辽河水资源现状及特点,以辽河干流区域为研究对象,建立评价指标体系,对人口密度、灌溉率等11个指标进行综合评价,采用层次分析法确定各指标权重,通过综合评价计算,对辽河干流2010年水资源承载能力进行评价。评价结果与实际情况基本一致,具有一定可信度,为辽河干流水资源开发利用提供科学依据。     

流域系统治理下的龙河下游河段健康评价研究

河流健康评价是开展流域规划、系统治理和生态修复工作的基础。廊坊龙河下游河段生态脆弱,水体流动性差、水环境状况不容乐观。为准确评价人类活动严重干扰下的河流生态健康状况、识别生态系统中脆弱性因子,基于层次分析法构建龙河下游健康评价指标体系,从水文完整性、物理结构完整性、化学完整性、生物完整性、社会服务功能完整性5个方面进行河流健康评价。龙河廊坊段总体上处于健康状态,评价得分为75.18分。评价结果表明：龙河流域水资源开发利用率大,湿地保留状况不佳,河岸带人工干扰程度大,上游来水水质较差等。提出的评价方法为受人工控制严重的河流开展健康评价提供方法参考。     

水库河道供水对辽河干流水质影响评价

本文通过大量的水质实测资料,分析了辽河干流水质污染状况,评价了水库供水对辽河干流水质状况的影响,指出水质影响评价对辽河干流水环境治理具有重要的指导意义.     

基于空间异质性的水资源生态脆弱性评价方法

常规的水资源生态脆弱性评价方法主要是以空间生态修复为主,未考虑潜在的生态脆弱度,导致生态脆弱性评价效果不佳。因此,设计了基于空间异质性的水资源生态脆弱性评价方法。提取水资源生态脆弱性空间分布特征后,分析生态脆弱性的潜在因素。然后结合空间异质性特征,处理生态脆弱性指标,确定水资源生态脆弱的因果关系。最后,构建水资源生态脆弱性评价模型,建立脆弱度评价等级。采用实例分析的方式,验证了该评价方法的评价指标与实际指标相一致,评价效果更佳,能够应用于实际工作中。     

辽河干流物理生境完整性灰色综合评价

通过对相关影响因子的分析,提出了评价指标体系及评价标准。根据选取的各指标的特点,采用灰色聚类方法进行定量综合分析,通过灰色聚类综合模型在辽河物理生境完整性评价上的应用,验证了该模型的可行性和有效性。评价结果表明,辽河干流物理生境完整性程度总体上处于"一般"的状态,需要给予更多的保护。     

辽河干流大张生态抗旱临时蓄水工程改造

近几年来,辽河流域持续性干旱,加上辽河上游水质污染严重,危害到流域十分脆弱的生态环境。大张生态抗旱临时蓄水改造工程是在辽河干流河道干旱缺水条件下进行生态建设的一种探索和尝试。文章介绍辽河干流大张生态抗旱临时蓄水工程概况和橡胶坝、钢坝闸、生态护坡及湿地的设计,以期为今后河道生态建设进一步完善提供参考。     

生态河岸带的概念及功能

生态河岸带是以自然为主导的,能够维持物种多样性、减少对资源的剥夺、维护生态系统的动态平衡,对提高系统的自我调节、自我修复能力、改善人类生活环境等方面具有重要的意义。生态河岸带具有结构稳定性、景观适宜性、生态健康性以及生态安全性等特征。生态河岸带是一个非常重要的生态系统,它具有自然保护功能、社会保护功能以及休闲娱乐功能。根据其功能的差异,从纵向和横向上,可以将生态河岸带分成不同的功能区域。     

Occupancy Patterns of Mammals and Lentic Amphibians in the Elwha River Riparian Zone Before Dam Removal

The downstream transport of sediments and organics and upstream migration of anadromous fishes are key ecological processes in unregulated riverine ecosystems of the North Pacific coast, but their influence on wildlife habitats and populations is poorly documented. Removal of two large hydroelectric dams in Washington's Elwha Valley provides an unprecedented opportunity to study long‐term responses of wildlife populations to dam removal and restoration of these key ecological processes. We compared pre‐dam removal patterns in the relative abundance and occupancy of mesocarnivores, small mammals and lentic amphibians of the Elwha River riparian zone above, between and below the dams. Occupancy of riparian habitats by three mesocarnivore species diminished upriver but did not appear to be closely linked with the absence of salmon in the upper river. Although the importance of salmon in the lower river cannot be discounted, other gradients in food resources also likely contributed to observed distribution patterns of mesocarnivores. Abundance and occupancy patterns within congeneric pairs of new world mice (Peromyscus spp.) and shrews (Sorex spp.) indicated that closely related species were negatively associated with each other and responded to habitat gradients in the riparian zone. The availability of lentic habitats of amphibians was highly variable, and occupancy was low as a result of rapidly changing flows during the larval development period. We speculate that long‐term changes in habitat conditions and salmon availability following dam removal will elicit long‐term changes in distribution of mesocarnivores, small mammals and amphibians. Long‐term monitoring will enhance understanding of the role of fish and restored ecosystem processes on wildlife communities along salmon‐bearing rivers in the region. Copyright © 2013 John Wiley & Sons, Ltd.     

水库运行对下游河岸潜流带水位-温度影响研究

选取浙江省新安江大坝下游尾水至富春江水库某一河段作为试验场地,实时监测同一河流剖面的河道水位、温度以及河岸水位与温度分布。通过分析侧向潜流交换流量,定量描述侧向潜流交换的空间非均质性和动态特征,刻画河岸潜流带与河道水体水位、温度之间的响应关系。结果表明:本次试验剖面上的侧向潜流交换流量变化范围为-8.36~3.87 m2/s,监测时间段内单位长度上的潜流交换量可达2.49 m2;河岸带侧向潜流区同一剖面不同观测井处的潜流流量呈线性相关,且离河道越远,潜流区水位波动振幅消减越多,响应越滞后,潜流交换流量越小;受水库下泄水流影响,河道水温日波幅很小,河岸含水层具有显著的垂向温度分层。在垂直方向上,冬季浅层河岸温度较低,深层河岸温度较高,夏季则相反,同时浅层温度梯度较大,尤以地面以下0.8~1.7 m范围内温度梯度最大,深层温度梯度小;在水平方向上,离河道越远,受河道入渗水影响越小,温度越高。揭示了水库运行对下游河岸潜流带的影响规律,为河流潜流带生态影响评估提供参考。     

农业小流域土地利用格局变化对氮素输出的影响——以丹江口库区胡家山小流域为例

流域土地利用格局对农业非点源污染氮素输出具有重要的影响。以丹江口库区胡家山小流域为研究对象,分析2008～2016年土地利用类型变化对流域总氮输出的影响,以期为丹江口库区生态清洁小流域建设提供参考。结果表明:2008～2016年,流域出口处总氮年平均浓度从5. 13±4. 2 mg/L降低为2. 06±0. 62mg/L;总氮输出负荷由49 025 kg/a降低至21 578 kg/a,总氮输出负荷减少56. 0%。对比分析流域生态治理工程实施情况,发现坡改梯、退耕还林等水土保持治理与植被恢复措施在有效控制水土流失的同时,还在减少流域氮素输出中发挥了重要作用。经相关分析,流域内林地、耕地、居民地的空间分布格局对流域氮素输出均有影响,其中100 m河岸带范围为流域总氮负荷输出的主要区域。有效控制胡家山小流域100 m河岸带尺度的氮素流失,可显著降低流域总氮输出负荷。     

Modelling changes in trout habitat following stream restoration

Stream restoration was implemented on the Upper Arkansas River near Leadville, Colorado, to improve brown trout (Salmo trutta) populations. Metals pollution and channel disturbance associated with historic mining, land use, and water development degraded aquatic and riparian habitat. Changes in instream habitat quality following restoration were investigated with a before–after–control–impact study design. Baseline, as‐built, and effectiveness surveys were conducted in 2013, 2014, and 2016, respectively. Two‐dimensional hydrodynamic modelling with River2D was used to estimate weighted usable area (WUA) for adult, juvenile, fry, and spawning brown trout across a range of flows. WUA was calculated from habitat suitability curves for velocity, depth, and channel substrate. Foraging positions (FP) and habitat heterogeneity were also evaluated as indices of habitat quality. All results were analysed with analysis of variance. At impact sites, WUA increased by 12.2% from 2013 to 2014 but decreased by 10.2% from 2014 to 2016, whereas FP increased by 24.8% from 2013 to 2014 but decreased by 26.1% from 2014 to 2016. Spawning habitat increased 53.3% from 2014 to 2016 at impact sites. The 15.4% increase in depth variability from 2013 to 2016 indicates that habitat heterogeneity was enhanced at impact sites. No changes in WUA, FP, or habitat heterogeneity were observed at control sites. Although changes in WUA and FP suggest that initial habitat improvements were not sustained, increased spawning habitat and depth heterogeneity suggest otherwise. Our results highlight the value of monitoring strategies that utilize multiple lines of evidence to evaluate restoration effectiveness, inform adaptive management, and improve restoration practices.     

鄱阳湖滨岸带对N素的净化及其影响因素

以鄱阳湖周边的土壤、水体为研究对象,在调查取样的基础上对典型滨岸带中N素分布及运移进行分析,利用主成分分析法对影响滨岸带对N素净化效果的因素进行排序。结果表明:鄱阳湖滨岸带采样点土壤TN质量比平均值为(0.721±0.275)mg/g,空间差异性大,且周边用地土壤TN质量比普遍高于临水区;水体TN质量浓度表现出周边内陆水体高于近岸湖水、汛前高于汛后的特征;滩地式滨岸带中的土壤TN质量比随滨岸带缓冲宽度增加而减少,且比值普遍低于堤岸式结构;滨岸带结构对N素净化率影响显著,滨岸带的净化效果与结构形式和植被配置有关。     

Responses of obligate versus facultative riparian shrubs following river damming

Riparian or streamside woodlands include obligate riparian trees and shrubs (obligates) that are restricted to streamside zones, and facultative riparian species that are abundant in, but not restricted to the riparian areas. Due to their distinctive life history requirements, it may be predicted that the ecological specialist obligates would be more vulnerable than the facultative generalists to impacts from river damming and flow regulation. We tested this along the Snake River through Hells Canyon, USA, where two native riparian shrubs dominate: the obligate sandbar willow (Salix exigua), and the facultative, netleaf hackberry (Celtis reticulata). We assessed riparian conditions over the past century by comparing ground‐level and aerial photographs taken after 1907 and in the 1950s in advance of three dams, versus recent conditions. These comparisons revealed three changes downstream from the dams: (1) the depletion of surface sands and sandbars and (2) reductions in sandbar willow versus (3) the proliferation of hackberry in dense bands above the typical high‐water line. The willow decline probably resulted from the depletion of sand following sediment trapping by the reservoirs, combined with changes in the seasonal water flow pattern. The increase in hackberry may have resulted from a beneficial ‘irrigation effect’ of daily water releases for power generation during the summer. The opposing responses reflect the plants' differing life histories and may partially resolve impacts of river regulation on alluvial sediments versus the instream flow pattern. We consider other riparian studies that suggest that obligates such as cottonwoods (Populus angustifolia, P. deltoides and P. fremontii) are highly vulnerable to river regulation, while facultative trees and shrubs such as trembling aspen (Populus tremuloides), wolf‐willow (Elaeagnus commutata) and velvet mesquite (Prosopis velutina) are more resilient. These results suggest that conservation of riparian woodlands should emphasize the ecological specialist obligates, while facultative species may be less vulnerable to river regulation. Copyright © 2009 John Wiley & Sons, Ltd.     

基于正交试验法的河岸带水热耦合模型敏感参数识别

为了研究河岸带水热耦合模型参数对温度及侧向潜流交换速率有限元计算结果的影响,基于正交试验法,对影响河岸带温度T和侧向潜流交换速率|v_x|的水热耦合模型进行敏感参数识别。结果表明：孔隙率n对河岸带水热耦合模型温度输出结果的影响最大;对于侧向潜流交换速率,水力传导率k_s的影响最大,而其他参数的影响均较小。因此,在进行河岸带水热耦合模型参数反演或校正时,应将模型中的孔隙率和水力传导率作为重点参数,而敏感程度低的参数可通过工程类比的方法进行确定,这样既可以保证计算精度,又可以提高计算效率。     

和田河干流河道径流损失与植被生态需水关系研究

和田河干流植被生态需水量是多少?河道渗漏水量能否满足两岸植被的生态需水?为了回答这两个事关和田河中下游河道整治必要性的基础问题,本研究定量分离河道损耗水量,探究河道渗漏水量与天然植被生态需水之间的定量响应关系,结果表明:(1)多年平均来水条件下,和田河干流河损量约为6.46×10~8m~3,其中,蒸发量与渗漏量分别为3.5×10~8和2.65×10~8m~3,各占河损量的58.88%和41.12%;(2)和田河干流天然植被的生态需水量1.37×10~8m~3,河道渗漏水量可以满足植被生态水量需求。因此,本研究认为开展河道整治,不仅不会影响干流植被生态需水,还可以减少水面蒸发,提高和田河输水能力,更有利于开展生态水量调度,保护和恢复干流天然植被。     

大汶河流域水生态系统健康评价研究

以大汶河流域为研究对象,基于2016年10月流域水生态调查数据,采用综合污染指数法、鱼类完整性指数法、层次分析法分别对水质、鱼类、河岸带进行健康评价,并在此基础上采用层次分析法对大汶河流域水生态系统进行综合评价。结果表明:大汶河流域水生态系统健康状况整体较差,较差和极差状态的点位分别占总采样点的50.0%和41.7%,健康等级为一般的采样点位仅占8.3%。从不同评价内容来看,该流域水质状况较差,其中大汶河南支、瀛汶河南段和汇河支流水质最差,为劣Ⅴ类水;在鱼类完整性评价中,24个采样点中1个采样点为健康,10个采样点为亚健康,13个采样点为一般,分别占总点位数的4.2%、42.6%和53.2%,没有较差和极差的采样点;河岸带生境状况评价结果整体较好,未出现河岸带生境较差的采样点。     

Riparian vegetation restoration: Does social perception reflect ecological value?

Social‐ecological contexts are key to the success of ecological restoration projects. The ecological quality of restoration efforts, however, may not be fully evident to stakeholders, particularly if the desired aesthetic experience is not delivered. Aesthetically pleasing landscapes are more highly appreciated and tend to be better protected than less appealing landscapes, regardless of their ecological value. Positive public perception of restoration actions may therefore facilitate stakeholder involvement and catalyse recognition of ecological improvement. Here we aim to contrast aesthetical perception and ecological condition in headwater river reaches restored through passive ecological restoration in study areas in Portugal (Alentejo) and France (Normandy). We recorded structural and functional indicators of riparian vegetation to monitor the ecological condition of study sites along a passive restoration trajectory. Aesthetical perception indicators were assessed through stakeholder inquiries developed under a semantic differential approach. We analysed perception responses to changes in the riparian ecosystems resulting from passive ecological restoration across different geographical contexts and social groups. The analysed social groups comprised stakeholders (environmental managers and landowners) and university students (landscape architecture and geography students). Results indicate that (a) visual preferences often do not reflect changes in ecological condition, (b) perception of the restoration process is strongly context dependent, and (c) experience and cultural background affect perception of ecological condition across the different social groups analysed. Clear identification of relevant stakeholder groups (those interested in or directly affected by restoration), effective communication, and stakeholder engagement are therefore essential for assuring the success of river restoration projects.