Environmental assessment of boreal rivers using fish data – a contribution to the Water Framework Directive

Abstract A fish‐based assessment method was developed to estimate the ecological status of boreal rivers. Electric fishing data were collected from 902 rapids, together with information on the land use, channel modification and water chemistry. Discriminant function analysis was used to select fish variables that most correctly classified the undisturbed reference sites and human impacted sites into exact classes. The relationship between the level of human alteration and fish metrics was examined. Five metrics were selected for the index: the number of fish species, proportion of sensitive species, proportion of tolerant species, density of cyprinid individuals and the density of age‐0+ salmonids. The value for each metric (between 0 and 1) was calculated according to a point estimate for classical probability. The index is used to estimate the ecological classification of rivers according to the EU Water Framework Directive.     

Assessing freshwater fish sensitivity to different sources of perturbation in a Mediterranean basin

Abstract –  The accuracy of bioassessment programmes is highly limited by the precision of the systems used to derive sensitivity–tolerance values for the organisms used as indicators. We provide quantitative support to the objective evaluation of freshwater fish species sensitivity to different sources of disturbance, accounting for co-variation issues not only between perturbations and natural gradients (especially river size), but also between different perturbations. With this aim, we performed two different principal component analyses: (i) on a general environmental matrix to obtain a perturbation gradient independent of river size effects and (ii) on human impairment-related variables to extract independent synthetic perturbation gradients. Then, we checked each species responses to those gradients to assess their sensitivity–tolerance through an available-used chi-squared analysis in the first approach and through a t -test/ ancova analysis in the second one. In this way, we obtained sensitivity–tolerance which could be included in future bioassessment tools, enabling effective evaluations.     

大型底栖动物快速生物评价指数在城市河流生态评估中的应用

为提供更加全面和有效的生态评估方法用以指导城市河流修复和保护,2017年3-4月选择深圳典型城市化区域河流,设置21个监测样点,开展大型底栖动物快速生物评价指数的适用性研究。分别选择生物多样性指数、群落结构指数、敏感性指数和耐污性指数,在评估不同指数适用性的基础上,筛选和构建用于城市河流健康评价的大型底栖动物快速生物评价综合指数。龙岗河大型底栖动物共采集到28科43种,寡毛类是龙岗河的主要优势类群。基于底栖动物群落结构特征对6个大型底栖动物快速生物评估指数进行了比较和分析,其中3种指数较适用于龙岗河城市河流健康评估。在考虑各参数离散度和相关性的前提下,可选择物种数、寡毛类相对丰度和科级耐污生物指数(Family Biotic Index, FBI)构建综合指数用于深圳市河流快速生物评价。健康评价的结果表明龙岗河2个样点为"理想状态",6个样点属于"亚健康"等级,其余13个样点处于"不健康"和"病态"。我国城市河流的有机污染总体较重,以大型底栖动物耐污类群或者敏感类群构建的快速生物评价指数能够较为灵敏地指示河流生态修复成效。     

利用水生昆虫评价南昆山溪流的水质

１９９４年９月，在南昆山溪流上设置３个样点，用综合定性取样法，共采获水生昆虫８目，４１科，６７属，１０４咱，共计９５５头，其中：毛翅目１２科，１７属，３０种；蜉蝣目９科，１８属，３０种；Ｊｉ翅目２科，８属，１２种；蜻蜓目８科，１２属，１４种；双翅目４科，４属，９种；鞘翅目３科，４属，４种；半翅目２，２属，２种；广翅目１科，２属，３种。利用Ｓｈａｎｎｏｎ－Ｗｅｉｎｅｒ多样性指数，ＥＰＴ种类丰富度，生     

海南省文澜江底栖动物群落结构及其水质生物学评价

为了解海南省临高县文澜江流域底栖动物群落结构特征,探索适宜的水质生物学评价方法,为文澜江流域环境监测、环境评价和科学管理提供数据参考。于2014年11月对文澜江流域17个点位底栖动物群落结构进行调查,并采用5种生物指数对水质现状进行了评价。结果表明,文澜江流域共采集底栖动物56种,隶属4门、7纲、29科,其中水生昆虫占绝对优势,共38种,占总数的67.86%;底栖动物密度和生物量分别为376.11个/m~2和200.79 g/m~2;多足摇蚊属(Polypedilum sp.)、米虾属(Caridina sp.)和环棱螺属(Bellamya sp.)为优势种,优势度分别为0.16、0.04和0.03。采用Goodnight-Whitley修正指数(GBI)和生物指数(BI)对文澜江流域水质整体评价结果均为清洁;采用Shannon-Wiener多样性指数、Margalef丰富度指数和生物学污染指数(BPI)的流域水质整体评估结果均为轻污染,3种水质生物指数评估结果基本相似,并与常规水质监测结果基本吻合。以水产养殖为主的水库出水口和流经临高县县城河道的水质处于中度污染程度,表明水产养殖废水、城市生活污水等对底栖动物的物种组成和群落结构造成了一定影响。     

梵净山自然保护区马槽河秋季水生昆虫调查及水质评价

水生昆虫属于节肢动物门(Arthropdoda)昆虫纲(Insecta).为了了解梵净山水生昆虫资源的现状及梵净山水质状况,2013年10月对梵净山马槽河进行实地调查.共采集水生昆虫标本419个,共计13种,分别属于6目10科12属.其中,蜉蝣目(Ephemeroptera)、鞘翅目(Plecoptera)和毛翅目(Trichoptera)个体数量之和占水生昆虫标本总数量的95.94％,为3大优势类群.对马槽河的水质现状进行评价,利用科级水平生物指数FBI(Family-Level Biotic Index)以及Shannon-Wiener(香农-维纳)多样性指数两种水质生物学评价方法,分析得出马槽河水质状况为清洁.     

茂兰喀斯特森林溪流水生昆虫群落构成及水质生物评价

对茂兰国家级自然保护区6条溪流中水生昆虫进行采集与鉴定,分析水生昆虫群落组成、结构、特征和ETP昆虫季节变化.共采集到水生昆虫11 783个,分别隶属7目41科,蜉蝣目、半翅目和毛翅目为三大优势类群,其个体数占总个体数的58.55％;香农—威纳多样性指数水质评价表明西竹溪流水质为轻度污染外,其余5条溪流的水质都能达到清洁标准;科级水平生物指数（FBI）的评价表明6条溪流均为清洁标准以上.     

Assessing electric fishing sampling effort to estimate stream fish assemblage attributes

The EU Water Framework Directive (WFD) obligates authorities to assess the ecological status of rivers. The sampling of the fish assemblage must be based on a reliable and cost‐effective monitoring programme, and it should be optimised to measure the ecological quality cost‐effectively. The efficiency of single‐pass versus three‐pass backpack electric fishing was measured to assess ecological status. The data included 295 electric fishing samplings from 137 rivers in Finland and a 5‐year data series from six small forest streams in mid‐eastern Finland. Compared with three‐pass electric fishing, single‐pass electric fishing in the same area increased the risk of missing rare fish species and species with low catchability. The concordance of the calculated fish metrics (e.g. proportion of tolerant and intolerant species) between one‐ and three‐pass measurements was, however, high, suggesting that single‐pass electric fishing was a suitable sampling procedure to evaluate ecological status. Increasing the area sampled by single‐pass removals stabilised the variances in the fish metrics and similarity indexes. It was concluded that in small streams electric fishing an area 24–27 times the stream width and in general a minimum of 300 m², but preferably more than 450 m², was adequate to estimate fish assemblage attributes reliably in boreal streams.