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1.
本文介绍了新西兰常用的大型无脊椎动物群落指数(MCI)和大型无脊椎动物群落数量指数(QMCI)的原理及使用方法,并利用MCI和QMCI对新西兰惠灵顿地区40条河流53个监测点进行评价.结果表明:MCI和QMCI均与河流营养指标呈极显著相关关系,可用来监测和评价水体的营养污染状况;二者快速准确地监测出惠灵顿地区河流水质总体良好,但部分河流污染严重,并分析了污染的原因.MCI与QMCI存在极显著相关关系,但MCI与营养指标间的相关关系大于QMCI,可以准确地反映出水体中营养元素的富集状况. 相似文献
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2011年夏、秋季在上海市全境主要河流的83个断面进行大型底栖动物的采样, 共获取底栖动物20个分类单位(种), 其中软体动物、环节动物和节肢动物分别占50%、30% 和20%。选取常见的28个生物指数分别进行计算, 并采用非参数统计检验方法筛选出8个敏感生物指数。通过记分法对8种敏感生物指数统一量纲后, 获得数值范围为8-40的综合生物指数, 运用四分法划分了判别河道水环境质量的生物基准: 32-40, 较好(Good); 24-31, 一般(Fair); 16-23, 污染(Poor); 8-15, 严重污染(Very poor)。9个断面未发现活体生物, 定为超严重污染(Super poor)。依照生物基准比较上海市41个代表性断面近5年主要水质理化指标, 基本反映出水质理化指标的空间差异性, 该综合生物指数及判别基准也可适用于评价平原河网地区的河道水质状况。 相似文献
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底栖生物完整性指数(B-IBI)是最为广泛应用的水生态系统健康评价指数之一。根据2009-2010年期间赣江流域60个采样点的底栖动物数据(15个参照点, 45个受损点), 对17个生物参数进行分布范围、判别能力和Pearson相关性分析, 确定了B-IBI指数体系由总分类单元数、甲壳和软体动物分类单元数、甲壳和软体动物%和BI指数构成。采用比值法统一各生物参数量纲, 将各个生物参数分值加和得到B-IBI指数值。根据参照点的B-IBI值的25%分位数值最终确定赣江流域河流健康评价标准。评价结果表明, 赣江流域60个采样点中19个为健康, 19个为亚健康, 14个为一般, 8个较差。综合来看, 赣江流域河流处于健康-亚健康状态: 上游各支流中绵水、贡江、上犹江和桃江为健康状态, 章水、濂水、梅江和平江为较差状态; 中游各支流健康评价结果多为健康-亚健康状态, 而乌江为较差状态; 下游各支流为健康-亚健康状态; 赣江干流上健康评价的结果均为健康。 相似文献
4.
基于不同生物指数的罗源湾生态环境质量状况评价 总被引:4,自引:0,他引:4
将国外已经成功应用的两类生态环境质量状况评价指数:严格基于底栖生物敏感度分类的AZTI海洋生物指数(AZTI marine biotic index,AMBI)和BENTIX指数,以及包含AMBI、香农多样性指数(H ')和物种丰度的复合指数——多因子AZTI海洋生物指数(multivariateAMBI,M-AMBI)应用于罗源湾,并将这两类指数的评价结果与我国常用的基于群落结构的H '进行相互校准,探讨这些指数在罗源湾的适用性,以期为我国近岸海域生态环境质量状况评价指数的选择提供一定的参考.结果表明:AMBI和BENTIX、M-AMBI和H'的评价结果基本一致.这3类指数在大部分站位的评价结果是一致的(13/16),不一致的站位都是AMBI和BENTIX的评价等级(优或良)高于M-AMBI和H'的评价等级(中).综合考虑物种丰度、个体丰度以及生物群组组成等信息,M-AMBI和H'的评价等级梯度明显(从中到优),评价结果更为合理.对于富营养化程度较高、沉积物有机富集程度低以及底栖生物组成以敏感种为主的罗源湾,选择H'和M-AMBI指数能够合理地评价生态环境质量状况. 相似文献
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生物完整性指数整合了多个单指标对干扰的响应特征,因此在综合评价水生态健康状况时具有良好的指标稳定性和响应敏感性。使用生物完整性指数开展自然河流水生态健康评价案例较多,但由于水体特征差异性导致指标选取存在不同,因此针对城市河流的评价研究案例并不多见。在参考以往研究基础上,结合城市河流的独有特征,将可以反映生态系统功能的功能多样性指标纳入备选指标体系,构建了天津市城市河流大型底栖动物完整性评价指数并开展了水生态健康评价。基于2023年4月和9月的水生态监测数据,分析了天津市城市河流大型底栖动物群落结构在枯水期和丰水期之间的变化情况。结果表明,大型底栖动物群落组成表现出显著的季节差异(ANOSIM: P=0.006, R=0.107),枯水期物种数要高于丰水期。梨形环棱螺(Bellamya purificata,Y枯水期=0.208,Y丰水期=0.192)、环棱螺属一种(Bellamya sp.,Y枯水期=0.045,Y丰水期=0.074)和纹沼螺(Parafossarulus striatulus,Y枯水期=0.033,Y丰水期=0.163)均是优势种,表现出季节稳定性。本研究构建了以水生昆虫分类单元数、BMWP指数、功能丰富度和功能分异度等为核心评价指标的天津市城市河流大型底栖动物生物完整性指数(IBI)。评价结果体现了在生物完整性的构建时引入功能参数的重要性。从空间分布看,上游河道保持了较好的生物完整性特征,而由于人类活动的介入导致中下游河道普遍偏差。从季节变化来看,不同地区的完整性变化存在差异,栖息地完整、植被覆盖度高和功能多样性高的参考点位对外部干扰的抵抗力和恢复力较好,因此受到的水文扰动小,而受损点位生物完整性普遍降低。营养盐和有机污染均影响了两个季节的IBI指数,而对于丰水期的大型底栖动物群落,水文变化也是不容忽视的重要因素。本研究结果从生物完整性角度为天津市河流生态系统的评价和保护修复提供了参考依据,同时也为其它类似河流生态系统提供了借鉴。 相似文献
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B-IBI指数是溪流生态系统健康评价常用指标之一。据安徽黄山地区溪流的33个底栖动物样点数据(11个参照点,22个受损点),对21个生物参数进行分布范围、Pearson相关性和判别能力分析,确定B-IBI指数由总分类单元数、EPT分类单元数、前3位优势分类单元%、粘附者%、敏感类群%和BI指数构成。分别用3分制、4分制和比值法统一各参数量纲,B-IBI指数值即为累加各构成指数的分值或比值。B-IBI箱线图分析表明,上述3种方法计算出的B-IBI值有较高判别能力(IQ=3),能很好地判别参照水体和受损水体,且3者之间具高相关性(r>0.90)。分别依据参照样点和所有样点B-IBI值建立健康评价标准,比较3分制、4分制和比值法对评价结果的准确性,表明用比值法统一各参数量纲并依据所有样点的B-IBI值建立的健康评价标准的准确性优于3分制和4分制法。建立了适合祁门县溪流生态系统健康评价B-IBI标准B-IBI>3.59健康,2.7~3.59亚健康,1.8~2.69一般,0.9~1.79差,B-IBI<0.9极差。祁门县21个样点的水体,14个健康,6个亚健康,1个一般。B-IBI与电导率(r=-0.62,p<0.01)和生境质量(r=0.65,p<0.01)显著相关。 相似文献
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湿地生态健康评价对于掌握湿地的健康状况、理解人类活动干扰对其影响及实施生态预警等有重要意义。鄱阳湖对于维持其流域甚至长江中下游的生态平衡十分重要,目前尚未建立起其较完善的生态健康评价指标体系。大型底栖无脊椎动物完整性指数(benthic macroinvertebrate-based index of biotic integrity, B-IBI)是广泛应用的湿地生态健康评价方法。基于30个采样点(7个参照点,23个受损点)的大型底栖无脊椎动物采样数据,构建鄱阳湖湿地的B-IBI指数,采用自然断点法划分非常健康、健康、一般、差和极差5个健康等级标准,据此评价湿地生态健康状况。研究表明:(1)基于B-IBI指数的鄱阳湖湿地生态健康评价结果为一般;(2)就采样点B-IBI分值而言,呈现出西部健康状况优于东部的格局,其中国家级自然保护区内状况较好,而工业区、城镇、农田及河流入湖口附近状况较差;(3)B-IBI指数与前期构建的景观发展强度指数(LDI)、栖息地环境质量指数(QHEI)以及植被完整性指数(V-IBI)具有显著相关性,表明基于不同指数的评价结果较为一致。本研究构建的B-IBI指数能为鄱阳湖湿地的生态健康评价和监测提供重要方法。 相似文献
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为了解石油开采对湿地生态系统的影响,2009年10月调查了黄河三角洲东营湿地34个样点的水体物理化学属性和大型底栖无脊椎动物群落结构。共获得3门6纲12目41科70属84个大型底栖无脊椎动物分类单元。Shannon-Wiener多样性指数(r=-0.446,P=0.02)和TN显著负相关,BI指数与理化指标无显著相关性;软体动物分类单元数与盐度(r=-0.422,P=0.028)显著负相关,与pH值(r=0.435,P=0.023)显著正相关;软体动物个体百分数同样与盐度(r=-0.395,P=0.041)呈显著负相关,与pH值(r=0.565,P=0.002)呈极显著正相关;寡毛类分类单元数与TN(r=0.524,P=0.005)极显著正相关。水体石油含量与生物指数无显著相关性。典范对应分析(CCA)显示,TN、pH、盐度是影响东营湿地底栖动物群落结构的主要环境变量,水体石油污染并不是主要的胁迫因子。寡毛类和软体动物是该地区对环境变化的主要指示生物类群。Shannon-Wiener多样性指数水质生物评价结果显示,溢洪河支流、广利河上游、挑河上游、东张水库属于清洁;轻污点位有9个,其余点位为中污或重污。 相似文献
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于2018年10—11月,对独龙江水系干流及支流的河流物理生境、水体理化性质和大型底栖动物进行调查,并根据独龙江自身特点,运用改进的河流健康综合评价指数对该地区生态系统健康状况进行了评价。结果表明:该地区调查样点中85.2%的样点处于健康状况,仅人口密集的乡镇附近健康状况处于亚健康水平,其中旅游业发达的独龙江乡健康状况最差。河流是水资源的重要载体,随着当地旅游业的不断发展,科学评价当地河流的健康状况可以为独龙江河流生态系统修复、水资源的合理开发利用及可持续发展提供重要的科学依据。 相似文献
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1. When using benthic macroinvertebrate communities for bioassessment, temporal variation may influence judgement as to whether or not a site is degraded.
2. In a survey of sixteen reference and sixteen test sites in the upper Thames River catchment area (UTRCA) in south-western Ontario, Canada, consistent differences between summer and winter samples were found for taxon richness (increase; P = 0.06) and the Family Biotic Index (decrease; P = 0.11). A bioassessment based on these results would indicate better water quality in the same streams in winter relative to summer. No consistent pattern of seasonal difference was detected for Simpson's Diversity and Equitability, or percentage Dominant Taxon.
3. The Reference Condition Approach to bioassessment uses predictive modelling to explain variation in reference communities with the environmental conditions at these sites as predictors. The community at a test site is compared with that predicted by the model. Several predictive models were constructed using simple geographic and habitat characteristics (i.e. catchment area, distance to source, stream width, substrate and habitat diversity) as predictors. By including season of sampling in the models, we increased their predictive power and the ability of the bioassessment to detect degradation. The best results were achieved when separate predictive models were built for each sampling season. 相似文献
2. In a survey of sixteen reference and sixteen test sites in the upper Thames River catchment area (UTRCA) in south-western Ontario, Canada, consistent differences between summer and winter samples were found for taxon richness (increase; P = 0.06) and the Family Biotic Index (decrease; P = 0.11). A bioassessment based on these results would indicate better water quality in the same streams in winter relative to summer. No consistent pattern of seasonal difference was detected for Simpson's Diversity and Equitability, or percentage Dominant Taxon.
3. The Reference Condition Approach to bioassessment uses predictive modelling to explain variation in reference communities with the environmental conditions at these sites as predictors. The community at a test site is compared with that predicted by the model. Several predictive models were constructed using simple geographic and habitat characteristics (i.e. catchment area, distance to source, stream width, substrate and habitat diversity) as predictors. By including season of sampling in the models, we increased their predictive power and the ability of the bioassessment to detect degradation. The best results were achieved when separate predictive models were built for each sampling season. 相似文献
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1. Semi‐aquatic birds may be sensitive to altered water quality. While avian species are not used in the bioassessment of streams, they may complement the more common use of benthic macroinvertebrates and fish. We estimated the extent to which water quality can predict attributes of the populations of one common semi‐aquatic bird, the American dipper (Cinclus mexicanus). 2. First, we estimated dipper presence/absence in relation to water quality as measured by a multimetric assessment index and individual bioassessment metrics. Second, we estimated dipper territory area and reproductive success in response to variation in water quality. We studied the diet, territory area and fecundity of dippers and sampled benthic macroinvertebrates, water chemistry and physical variables at 32 sites with and 17 sites without nesting dippers. 3. Dipper presence was only weakly related to chemical, physical and commonly recorded bioassessment metrics such as per cent Ephemeroptera, Plecoptera and Trichoptera (%EPT). Dippers were strongly related to the abundance of their common prey, Drunella and Heptageniidae, which are only a small component of the commonly recorded bioassessment metrics. The variances in territory area and reproductive success were weakly predicted by water quality variables. 4. Dipper presence reflected disturbance as measured by their common prey, showing that lower abundance of these stream invertebrates affected this semi‐aquatic bird. We suggest dipper presence/absence might be used in multimetric indices of biotic integrity for the bioassessment of streams. 相似文献
13.
Use of Phytoplankton Assemblages for Monitoring Ecological Status of Lakes within the Water Framework Directive: The Assemblage Index 总被引:7,自引:0,他引:7
The ingress of an urban stream carrying high contaminant loads into a large coastal river originates a “dispersion plume”
subject to the hydrological conditions of a river affected by tidal influences. In the present study 21 sites within the “contaminant
plume” of the Riachuelo River in the Rio de la Plata were analysed on the same date in order to evaluate the biological status
of the area which receives this strong environmental impact, and to examine its effect on the zoobenthic communities. Diversity,
taxonomic richness, abundance, physico-chemical parameters and a biological index (IMRP) were used to assess the responses
of the macroinvertebrates. The correlation between exposure and effect was calculated by means of the exposure index (IEX).
The relationship between the macroinvertebrate communities and environmental variables was examined using CCA analysis. Conductivity,
Cr, BOD and COD, were most strongly correlated with Axis 1, suggesting the existence of a gradient of environmental degradation.
The most severely contaminated sites (IMRP= 1.1–2.5; IEX = 100–78%) were all characterized by a reduced community dominated
by Nematoda and Oligochaeta. A moderate response was observed between 1400 and 1600 m from the coast (IMRP = 2.6–3.9; IEX
= 36%) largely owing to the physico-chemical characteristics of the recipient river which contributed to moderating the effect
of the anthopogenic perturbation. For statistical validation, this area was compared with historical physico-chemical and
biological data, where OD and COD showed the same tendency throughout the 10-year period. 相似文献
14.
通过2011年滦河流域38个河段大型底栖无脊椎动物采集,探讨了河段尺度和流域尺度环境因子对大型底栖无脊椎动物分布的影响。其中,河段尺度因子包括水体/底质特征、河岸带特征和水质,流域尺度因子包括采样位置、流域土地利用结构和缓冲区土地利用结构。RDA(冗余分析)结果表明,河段尺度影响大型底栖无脊椎动物分布的关键因子为:细粒物质比例、河岸带植被盖度、河岸带人类干扰程度、河岸带农田比例、水面宽度和河道改造程度,总解释量为42%;流域尺度影响大型底栖无脊椎动物分布的关键因子为:纬度、海拔、流域内耕地面积百分比和流域面积,总解释量为32%。研究结果表明,河段尺度因子比流域尺度因子对于指示大型底栖无脊椎动物分布更为重要,在环境因子监测中应给以更多的重视。 相似文献
15.
【目的】松花江流域是中国最早的工业基地之一,其水生态环境遭到严重破坏,环境保护工作面临巨大挑战。开展松花江流域水质评价及典型生物类群多样性状况调查,可为松花江流域生态系统的保护和修复提供依据。【方法】于2016年7月调查整个松花江流域近岸的大型底栖动物群落组成和测定水质理化指标,开展其水质理化特征评价和生物指数评价,并探讨底栖动物群落分布与水环境因子间的关系。【结果】理化指标评价结果显示,南源松花江水质状况最差,处于中度污染;北源松花江处于轻度污染;梧桐河水质最好,处于良好状态。松花江流域3个河段的底栖动物群落结构存在空间差异性。另外,梧桐河的物种多样性最高,北源松花江次之,南源松花江最低。溶解氧和营养元素K的浓度是驱动底栖动物群落组成发生显著性差异的主要环境因子。生物指数评价结果显示,3个河段水质均处于轻度污染状态。【结论】松花江流域水质处于轻度到中度污染状态。有机污染是松花江流域面临的主要水质环境问题,对松花江流域底栖动物群落结构产生了显著影响。因此,控制有机质的输入是维持松花江流域水生态系统平衡的重要举措之一。 相似文献
16.
耐受值表现为水生生物在一定水平的干扰作用下生存和繁殖的相对能力,在生物学评价中起着不可或缺的重要作用。通过查阅文献资料、野外采样和实验室分析与鉴定,获得大沽夹河23个采样点1998~2007年环境要素数据和2006~2007年底栖大型无脊椎动物数据。应用等标指数法和算术平均法计算环境梯度值,利用加权加和法估算底栖大型无脊椎动物的耐受值,建立底栖大型无脊椎动物44个分类单元的耐受值谱。研究表明:(1)根据环境要素值和底栖大型无脊椎动物数据、采用数学方法估算底栖大型无脊椎动物耐受值,比专家经验或以生物多样性划分环境梯度等方法,更加客观;(2)耐受值谱表明,大沽夹河底栖大型无脊椎动物以敏感性和耐受性类型为主,过渡性类型较少。(3)与前人研究成果对比,耐受值在目、科分类单元比较一致,在属、种分类单元存在差异;(4)限于条件,底栖大型无脊椎动物分类鉴定有些粗略,环境梯度计算未包含底质、水文要素,需进一步改进。 相似文献
17.
Filipa M. S. Martins Mafalda Galhardo Ana F. Filipe Amílcar Teixeira Paulo Pinheiro Joana Pauprio Paulo C. Alves Pedro Beja 《Molecular ecology resources》2019,19(4):863-876
DNA metabarcoding can contribute to improving cost‐effectiveness and accuracy of biological assessments of aquatic ecosystems, but significant optimization and standardization efforts are still required to mainstream its application into biomonitoring programmes. In assessments based on freshwater macroinvertebrates, a key challenge is that DNA is often extracted from cleaned, sorted and homogenized bulk samples, which is time‐consuming and may be incompatible with sample preservation requirements of regulatory agencies. Here, we optimize and evaluate metabarcoding procedures based on DNA recovered from 96% ethanol used to preserve field samples and thus including potential PCR inhibitors and nontarget organisms. We sampled macroinvertebrates at five sites and subsampled the preservative ethanol at 1 to 14 days thereafter. DNA was extracted using column‐based enzymatic (TISSUE) or mechanic (SOIL) protocols, or with a new magnetic‐based enzymatic protocol (BEAD), and a 313‐bp COI fragment was amplified. Metabarcoding detected at least 200 macroinvertebrate taxa, including most taxa detected through morphology and for which there was a reference barcode. Better results were obtained with BEAD than SOIL or TISSUE, and with subsamples taken 7–14 than 1–7 days after sampling, in terms of DNA concentration and integrity, taxa diversity and matching between metabarcoding and morphology. Most variation in community composition was explained by differences among sites, with small but significant contributions of subsampling day and extraction method, and negligible contributions of extraction and PCR replication. Our methods enhance reliability of preservative ethanol as a potential source of DNA for macroinvertebrate metabarcoding, with a strong potential application in freshwater biomonitoring. 相似文献
18.
Biological and ecological traits of benthic freshwater macroinvertebrates: relationships and definition of groups with similar traits 总被引:14,自引:0,他引:14
Philippe Usseglio-Polatera† Michel Bournaud† Philippe Richoux† Henri Tachet† 《Freshwater Biology》2000,43(2):175-205
- 1 Relating species traits to habitat characteristics can provide important insights into the structure and functioning of stream communities. However, trade‐offs among species traits make it difficult to predict accurately the functional diversity of freshwater communities. Many authors have pointed to the value of working with groups of organisms as similar as possible in terms of relationships among traits and have called for definition of groups of organisms with similar suites of attributes.
- 2 We used multivariate analyses to examine separately the relationships among 11 biological traits and among 11 ecological traits of 472 benthic macroinvertebrate taxa (mainly genera). The main objective was to demonstrate (1) potential trade‐offs among traits; (2) the importance of the different traits to separate systematic units or functional groupings; and (3) uniform functional groups of taxa that should allow a more effective use of macroinvertebrate biological and ecological traits.
- 3 We defined eight groups and 15 subgroups according to a biological trait ordination which highlighted size (large to small), reproductive traits (K to r strategists), food (animal to plant material) and feeding habits (predator to scraper and/or deposit feeder) as ‘significant’ factors determining the ordination of taxa. This ordination partly preserved phylogenetic relationships among groups.
- 4 Seven ecological groups and 13 ecological subgroups included organisms with combinations of traits which should be successively more adequate in habitats from the main channel to temporary waters, and from the crenon to the potamic sections of rivers, and to systems situated outside the river floodplain. These gradients corresponded to a gradual shift from (1) rheophilic organisms that lived in the main channel of cold oligotrophic mountain streams to (2) animals that preferred eutrophic habitats of still or temporary waters in lowlands. The groups with similar ecological traits had a more diverse systematic structure than those with similar biological traits.
- 5 Monitoring and assessment tools for the management of water resources are generally more effective if they are based on a clear understanding of the mechanisms that lead to the presence or absence of species groups in the environment. We believe that groups with similar relationships among their species traits may be useful in developing tools that measure the functional diversity of communities.
19.
底栖大型无脊椎动物作为水环境监测的重要指示生物, 其群落结构和多样性能够有效地反映水环境的健康状况。为了更好地了解扬州宝应湖大型底栖动物的群落多样性, 本文于2015-2019年对扬州宝应湖底栖大型无脊椎动物进行野外调查和采样, 联合经典形态学和高通量测定DNA条形码方法进行物种鉴定, 进一步分析了这些大型无脊椎动物群落结构和多样性的年度变化, 并应用Shannon-Wiener指数(H′)和污染生物指数(biotic index, BI)对水质状况进行生物评价。结果显示: 共记录大型底栖动物3门5纲57种, 其中软体动物门23种, 隶属2纲9科(腹足纲7科15种, 双壳纲2科8种); 环节动物门寡毛纲12种, 隶属2科; 节肢动物门22种, 隶属2纲6科(软甲纲4科5种, 昆虫纲2科17种)。腹足纲是优势类群, 5年间的密度占比均在65%以上。优势种是赤豆螺(Bithynia fuchsiana)、槲豆螺(B. misella)和长角涵螺(Alocinma longicornis)。Margalef丰富度指数(2.27 ± 0.28)、Simpson优势度指数(0.82 ± 0.02)和Pielou均匀度指数(0.78 ± 0.08)在5年间呈现明显的波动变化。对水质状况的生物评价结果表明, 湖区水体环境在5年间均呈现不同程度的污染状态, 这与过度围湖水产养殖等经济活动引起水体富营养化有一定关系。 相似文献
20.
Structure and Dynamics of a Benthic Invertebrate Community in an Intertidal Area of the Tagus Estuary, Western Portugal: A Six Year Data Series 总被引:1,自引:0,他引:1
Gilda Silva José Lino Costa Pedro Raposo de Almeida Maria José Costa 《Hydrobiologia》2006,572(1):115-128
A predictive model, incorporating macroinvertebrate and environmental data, similar to that developed for Australian rivers (AUSRIVAS) and British rivers (RIVPACS) was constructed using a dataset collected from 23 reference (least altered) wetlands on the Swan Coastal Plain, Western Australia, sampled in summer and spring, 1989 and spring, 1990. Four main groups of reference wetlands were identified by UPGMA classification (using the Bray–Curtis dissimilarity measure). Distinguishing environmental variables identified by Stepwise Multiple Discriminant Function Analysis were: calcium, colour (gilvin), latitude, longitude, sodium and organic carbon. Observed to expected ratios of taxa with a >50% chance of occurrence (OE50) derived from the model for a suite of 23 test wetlands sampled in spring, 1997, were significantly correlated with pH and the depth of the sampling sites. Greater discrimination between the test wetlands was provided by the OE50 ratios than either raw richness (number of families) or a biotic index (SWAMPS). Results obtained for a subset of 11 test wetlands sampled with both a rapid bioassessment protocol (incorporating field picking of 200 invertebrates collected in 2 min sweeps from selected habitats) and a semi-quantitative protocol (incorporating laboratory picking of all invertebrates collected in sweeps along 10 m transects at randomly allocated sites) were not significantly different, indicating that the former could be used to reduce the time and costs associated with macroinvertebrate-based wetland monitoring programs. In addition to providing an objective method of assessing wetland condition, predictive modelling provides a list of taxa expected to occur under reference conditions, which can be used as a target in wetland restoration programs. The probable impediment to widespread adoption of predictive modelling for wetland bioassessment is the need to produce models tailored to specific geographic regions and specific climatic conditions. This may incur significant costs in countries, such as Australia, which span a wide range of climatic zones. 相似文献