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1.
吕光俊  熊邦喜  刘敏  杨学芬  覃亮  陈朋  徐微  刘俊利 《生态学报》2009,29(10):5339-5349
2006~2007年对湖北省4座不同营养类型水库的大型底栖动物群落结构和多样性进行周年研究,并进行了水质评价.共采集到底栖动物39种,其中寡毛类14种、水生昆虫19种、软体动物6种.以金沙河的底栖动物种类最多,达24种,其次为徐家河19种,道观河和桃园河各10种.4座水库优势种类各异,金沙河为多毛管水蚓(Aulodrilus pluriseta)、隐摇蚊(Cryptochironomus sp.)、多足摇蚊(Polypedilum sp.);徐家河为瑞士水丝蚓(Limnodrilus helveticus)、前突摇蚊(Procladius sp.);桃园河为多毛管水蚓(Aulodrilus pluriseta)、长跗摇蚊(Tanytarsus sp.);水质污染比较严重的道观河水库优势种类为霍甫水丝蚓(Limnodrilus hoffmeisteri)、大红德永摇蚊(Tokunagayusurika akamusi).各库底栖动物年平均密度和生物量分别为:金沙河316 8ind · m-2,1294.3mg · m-2 ;道观河318.2ind · m-2,430.7mg · m-2 ;徐家河330.3ind · m-2,517.4mg · m-2;桃园河209ind · m-2,325 3mg · m-2 .TN、TP、COD平均含量变幅分别为0.392~1.018、0.011~0.042、3.505~9.166mg · L-1;采用理化分析、Goodnight-Whitley指数、Shannon-Wiener指数、Margalef指数、Simpson指数、Pielou均匀度指数对水库的水质进行了综合评价,结果表明:金沙河水库属中营养型;徐家河和桃园河属中-富营养型;道观河水库属富营养型.对水库主要的物理化学因子与寡毛类、水生昆虫、软体动物密度,以及各类底栖动物之间进行矩阵分析,发现水生昆虫与水深呈负相关关系,随着水深的增加,其密度和种类下降,水深超过10m,下降的幅度更明显;寡毛类有从属于TN和TP含量的趋势, TP变化对底栖动物的影响更大;寡毛类、水生昆虫、软体动物三者之间无相关性.  相似文献   

2.
新疆额尔齐斯河是中国唯一流入北冰洋的河流,整个流域有着极为丰富的底栖动物资源。2012年7月、8月、10月与2013年5月分别对额尔齐斯河干流、5条主要支流以及附属水库的大型底栖动物群落结构特征进行了调查。结果表明:共采集大型底栖动物117种,其中水生昆虫106种(90.6%),软体动物6种(5.1%),寡毛类3种(2.6%),其他大型底栖动物2种(1.7%);优势种主要为似动蜉(Cinygmula sp.)、四节蜉(Baetis sp.)、直突摇蚊(Orthocladius sp.)、蜉蝣科(Ephemeridae sp.)、多足摇蚊(Polypedilum sp.)、摇蚊(Apedilum sp.)、霍甫水丝蚓(Limnodrilus hoffmeisteri)、短脉纹石娥(Cheumatopsyche sp.)、小蜉(Ephemerella sp.)、寡角摇蚊(Diamesa sp.);大型底栖动物的密度(P=0.558)与生物量(P=0.464)季节性差异不显著,年平均密度与生物量分别为519.05 ind·m-2、3.30g·m-2,大型底栖动物密度存在明显的空间差异,整体上上游(604.53 ind·m-2)高于下游(447.82 ind·m-2);大型底栖动物年平均Margalef指数、Shannon指数、Simpson指数、Pielou指数分别为1.12、0.53、0.65、0.52;聚类分析显示,多样性指数较低的185团北湾、布尔津河口、盐池、小635采样点聚为一类,其余各点聚为一类;利用科级生物指数(FBI)、Beck指数、Chandler生物记分制(CS)以及BMWP指数评价额尔齐斯河各段水质,整体上水质属轻度污染;Spearman相关性分析显示,水生昆虫的分布与水体透明度呈显著正相关,而寡毛类的分布与盐度、电导率和矿化度呈显著正相关,与电阻呈显著负相关,软体动物的分布与环境因子的关系不显著。  相似文献   

3.
高原深水湖泊抚仙湖大型底栖动物群落结构及多样性   总被引:6,自引:0,他引:6  
云南抚仙湖是我国典型的高原深水湖泊,20世纪80年代以来,随着人类活动的加剧,其水体营养水平不断提高,生态系统发生了显著变化。为揭示该湖底栖动物的群落特征及其对生态系统变化的响应,2005年正7月对大型底栖动物群落进行了调查。在抚仙湖18个断面110个样点中共采集大型底栖动物19属27种,大型底栖动物出现率为97.3%,平均密度为855ind./m^2,平均生物量为58.01g/m^2。在密度组成上软体动物(50.3%)〉摇蚊幼虫(32-3%)〉寡毛类(17.4%),优势种为花纹前突摇蚊(Procladius choreus)、长角涵螺(Alocinma tongicornis)和方形环棱螺(Bellamya quadrata),三者共占总密度的51.4%。寡毛类和摇蚊幼虫全湖性分布,而软体动物主要分布在沿岸区,各类群优势种均呈聚集分布。底栖动物在沿岸区生物量显著大于湖心区(P〈0.01),但两者之间密度差异不显著(P〉0.05);南区和北区之间的密度(P〉0.05)和生物量(P〉0.05)差异均不显著。相关分析表明,表层沉积物总有机碳、底层水体溶解氧是影响底栖动物密度分布的关键理化因子,而底层水体溶解氧是影响底栖动物生物量分布的关键理化因子。抚仙湖大型底栖动物群落的Pielou均匀度指数、Margalef丰富度指数、Simpson优势度指数、Shannon-Wiener多样性指数及改进的Shannon-Wiener多样性指数分别为0.74、2.88、0.87、2.40和20.84。沿岸区底栖动物多样性明显高于湖心区,主要是由于沿岸区分布有各种沉水植物,提高了底栖动物生境的异质性。与1980年调查结果相比,抚仙湖底栖动物多样性呈上升趋势,这与水体营养水平不断提高,沉水植物分布面积扩大有关。  相似文献   

4.
武汉东湖水网区底栖动物群落特征及其水质的生物学评价   总被引:5,自引:0,他引:5  
2008年4-9月间三次对武汉东湖水网区15个水体的底栖动物进行调查,共采集到大型底栖动物50种,隶属于16科41属,其中严东湖底栖动物种数最多,有28种;北湖、青潭湖和杨春湖仅2-3种,其他水体介于以上两者之间.定量分析表明,在超富营养及富营养湖泊中,优势类群均为寡毛类和水生昆虫摇蚊科种类,只是所占比例有所差异:中营养湖泊严东湖,密度上水生昆虫占优势,为总量的59.1%,生物量上软体动物占优势,为总量的96.4%;青山港中,密度上寡毛类占优势,为总量的63.6%,生物量上软体动物占绝对优势,为总量的99.1%.采用Shannon-Weaver多样性指数(H)、Goodnight-Whitley指数(GI)及Biotic Index 生物指数(BI)对东湖水网区水体及武汉周边的南北咀、肖四海的水质进行评价,结果显示BI的评价结果与湖泊现实情况基本相符,推荐Biotic Index生物指数作为东湖水网区底栖动物生物评价的指标.  相似文献   

5.
芦康乐  杨萌尧  武海涛  管强  张科 《生态学报》2020,40(5):1637-1649
分别于2018年5月和8月对黄河三角洲芦苇湿地19(淡水补给区11处,石油开采区8处)处采样点的底栖无脊椎动物和水体理化指标进行调查采样,运用统计方法分析两个区域物种组成、优势种、多样性、群落结构以及与环境因子的关系。结果表明:两季共采集到底栖无脊椎动物54种,主要以水生昆虫、腹足纲和软甲纲为主,淡水补给区和石油开采区各类群组成差异明显。独立样本T检验表明淡水补给区和石油开采区水体理化指标间差异显著(P0.05)。双因子方差分析显示,昆虫纲和腹足纲密度在两区域差异显著(P0.05),软甲纲和腹足纲密度在季节上差异明显(P0.05)。底栖无脊椎动物优势种共10种,淡水补给区指示物种8种,而石油开采区未发现有指示物种。聚类和非参数多维排序(nM DS)显示,底栖无脊椎动物群落结构相似性较低; RDA结果表明:淡水补给区底栖无脊椎动物群落结构主要受Cond,TDS,Sal,pH,Eh,HCO_3~-,SO_4~(2-)等环境因子的影响。石油开采区底栖无脊椎动物群落结构影响较大的环境因子为HCO_3~-、NH_4-N。  相似文献   

6.
于2015年4月(春季)、2015年6月(夏季)、2015年10月(秋季)、2016年1月(冬季),在海南东寨港红树林保护区潮间带进行多次采样,分选小型底栖动物,并测定沉积物中有机质和叶绿素a含量,分析不同季节东寨港红树林小型底栖动物丰度与有机质、Chla的相关性。研究结果,沉积物中小型底栖动物主要包括自由生活线虫、桡足类、涡虫、多毛类、寡毛类,线虫为优势类群;有机质含量为25.22%—93.41%,平均值为46.6%; Chla含量为0.188—6.303μg/g,平均值为1.731μg/g。相关性分析显示,春季小型底栖动物的丰度和Chla含量呈显著正相关(Pearson's r=0.684; P0.05),夏季小型底栖动物的丰度与有机质含量呈显著负相关(Pearson's r=-0.518; P0.05)。  相似文献   

7.
滇池大型无脊椎动物的群落演变与成因分析   总被引:3,自引:0,他引:3  
Wang CM  Xie ZC  Song LR  Xiao BD  Li GB  Li L 《动物学研究》2011,32(2):212-221
该文综合滇池大型无脊椎动物的历史资料,并结合2009—2010年的现场调查数据,对其群落演替进行了研究,并对群落衰退的成因进行了探讨。物种数下降明显,由20世纪80年代的57种降为现在的32种,群落的物种损失率高达44%。其中软体动物损失率高达75%:其次是水生昆虫(39%)。滇池全湖底栖动物密度为1776ind/m2(其中寡毛类1706ind/m2;摇蚊科68ind/m2)。近20年滇池全湖底栖动物的丰度比较发现,寡毛类的密度和生物量呈一种先急剧上升,而后明显下降的过程,而摇蚊科的密度和生物量呈现出减少的趋势。寡毛类中的耐污种相对丰度增加,如霍甫水丝蚓(Limnodrilus hoffmeisteri)成为绝对优势种,其平均相对丰度达到了74.1%。摇蚊科相对丰度减少,以前广泛分布的异腹鳃摇蚊(Einfeldiasp.)基本消失,取而代之的是羽摇蚊(Chironomus plumosus)、细长摇蚊(Ch.attenuatus)、中国长足摇蚊(Tanypus chinensis)等耐污种;软体动物种类变得单一,许多高原湖泊特有的软体动物均已消失,螺蛳(Margarya melanioides)、牟氏螺蛳(M.mondi)、光肋螺蛳(M.mansugi)在2009年被世界自然保护联盟列入了极危物种,滇池圆田螺(Cipangopaludina dianchiensis)也被列入了濒危物种。滇池的Shannon-Wiener多样性指数显著降低,尤其是草海物种多样性从20世纪50年代的2.70降到现在的0.30。半个多世纪以来总氮、总磷与物种数和多样性呈现显著负相关。底栖动物群落衰退的成因主要是生境破坏、水质恶化、蓝藻爆发、沉水植物消失、种质库匮乏等。  相似文献   

8.
大型底栖动物在人工湿地生态系统的物质循环和能量流动过程中发挥着重要作用,是保持湿地结构稳定、高效运行的重要因素。为了解大型底栖动物在人工湿地内的群落特征,于2013年8月—2014年5月对盐龙湖芦苇(Phragmites communis)、茭草(Zizania latifolia)、狭叶香蒲(Typha angustifolia)表流人工湿地的大型底栖动物群落进行调查。结合相对重要性指数(IRI)、多样性指数(Shannon-Wiener多样性指数,Pielou均匀度指数,Margalef丰富度指数)与相关性分析等手段,研究了不同植物配置下人工湿地大型底栖动物群落特征及其与环境因子的关系。调查共采集到大型底栖动物14种,主要优势物种为纹沼螺(Parafossarulus striatulus)、霍普水丝蚓(Limnodrilus hoffmeisteri)、长角涵螺(Alocinma longicornis)、摇蚊幼虫(Tendipes sp.),但不同植物配置下优势物种有所差别。芦苇、茭草及狭叶香蒲湿地的年均大型底栖动物密度分别为285、330、266个/m2,年均生物量分别为25.6、104.0、32.3 g/m2。茭草湿地的大型底栖动物群落在物种数量、均匀程度上要高于芦苇及狭叶香蒲湿地,而后两者多样性水平相当。茭草湿地底栖动物群落生物量与软体动物密度呈极显著(P0.01)正相关,总密度与水深呈显著(P0.05)负相关,环节动物的密度与全氮(STN)、有机质(SOM)之间分别呈极显著(P0.01)、显著(P0.05)正相关。研究为今后人工湿地生态系统的设计、管护以及长效运行提供新的思路。  相似文献   

9.
于2014和2015年7月对新疆伊犁河支流喀什河和巩乃斯河共14个采样点的大型底栖无脊椎动物进行了调查研究, 比较分析了自然、受损、坝下和保护区4种生境的大型底栖动物群落结构特征。共采集大型底栖动物14435头, 属10目39科81属(种), 其中水生昆虫、软体动物、寡毛类分别占93.8%、2.5%和3.7%。对不同生境大型底栖动物群落结构特征进行了分析比较, 结果表明: 自然生境在物种数、优势物种数、EPT物种数、密度和物种多样性方面均高于其他3种生境, 而坝下生境均最低, 保护区生境底栖动物群落结构优于受损生境和坝下生境。冗余分析(RDA)结果共解释了物种数据累计方差的54.1%, 流速、电导率、水温和海拔是影响伊犁河底栖动物分布的主要因素(F=2.28—4.34, P<0.05)。  相似文献   

10.
对徐州市京杭运河市区段和市区湖泊云龙湖进行了大型底栖动物群落结构及影响因子的比较研究。结果显示:城市河流和湖泊生态系统中,大型底栖动物种类较少、群落结构相对简单,其中城市河流大型底栖动物的组成主要为水栖寡毛类和软体动物,城市湖泊大型底栖动物主要组成为水栖寡毛类和摇蚊幼虫。除Margalef物种丰富度指数外,河流与湖泊的其他群落指数相差不大。聚类分析将两类生态系统中的大型底栖动物群落明显分为两组。CCA结果显示云龙湖大型底栖动物群落的主要影响因子是p H和溶解氧,京杭运河徐州市区段大型底栖动物群落的主要影响因子是总磷和化学需氧量。  相似文献   

11.
应用底栖动物完整性指数B-IBI评价溪流健康   总被引:68,自引:15,他引:53  
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   

12.
2011年夏秋季,在上海市全境83个河道断面开展了大型底栖无脊椎动物采样,共获取底栖动物20个分类单位(种).9个极严重污染断面未采集到活体大型底栖生物,生境基本丧失.其余74个有活体生物断面,采用三种常用生物指数:Shannon-Wiener多样性指数、Hilsenhoff耐污指数、Goodnight修正指数分别进行计算及评价.Shannon-Wiener多样性指数判别为25个严重污染和49个重污染断面;Hilsenhoff耐污指数划分38个重污染、5个中污染和31个轻污染断面;Goodnight修正指数划分33个重污染、2个中污染和39个轻污染断面.与典型河道断面的水质理化指标监测值进行对照,Shannon-Weiner多样性指数对河道水质评价的准确度较低,Hilsenhoff生物指数和Goodnight修正指数的水质评价效率及准确度均较高,断面污染等级与水质理化指标基本对应.  相似文献   

13.
基于B-IBI指数的温榆河生态健康评价   总被引:10,自引:0,他引:10       下载免费PDF全文
杨柳  李泳慧  王俊才  杨玉格  丁振军 《生态学报》2012,32(11):3313-3322
基于温榆河底栖动物和水质采样数据,采用底栖动物完整性指数(B-IBI)方法,进行温榆河生态健康评价,并探求河流水质与B-IBI指数的相关性。通过分布范围、判别能力以及相关性分析等,确定研究区B-IBI指标体系,包括总分类单元数、总生物量、优势分类单元个体相对丰度、敏感类群分类单元数、生物指数和粘附者个体丰度6个指标。根据参照点25%分位数确定温榆河底栖动物完整性评价标准,即B-IBI>1.821为健康,1.366—1.821为亚健康,0.910—1.366为一般,0.455—0.910为较差,0—0.455为极差。结果表明,温榆河27.3%河段处于健康状态,9.1%河段处于亚健康状态,13.6%河段处于一般状态,50%河段处于较差和极差状态。河流水质与B-IBI指数的相关系数为-0.549,表明生物指标作为水体评价的补充指标十分必要。  相似文献   

14.
Canonical correspondence analysis (CCA) was used to explore the relationship between measured environmental variables and surficial diatom (Bacillariophyceae) assemblages in alkaline lakes from southeastern Ontario. Total nitrogen (TN), watershed area, alkalinity, and maximum depth each explain significant (P ≤ 0.05) directions of variance in the distribution of diatom taxa. TN was highly correlated to total phosphorus (TP) (r = 0.92), chlorophyll a (r = 0.86), and Secchi depth (r =0.77). When a series of CCAs were run with the first axis constrained to each of these variables in turn, the ratio of the eigenvalue of the first axis to that of the second axis (λ1/λ2) was highest for TN, indicating that TN best explained the distribution of the diatom assemblages in this set of lakes. Furthermore, results of Monte Carlo permutation tests indicated that these four variables did not act independently on the diatom assemblages. Therefore, TN was selected to represent these four closely related variables to infer lake trophic status. Weighted-averaging regression and calibration (with classical deshrinking) were used to develop transfer functions to infer TN from the relative abundances of 83 diatom taxa recovered from the surficial sediments of 51 lakes. There was a good correlation between diatom-inferred TN concentrations and measured TN concentrations (r2= 0.75, n = 51). The weighted-averaging regression and calibration model was used to infer lake trophic status (represented by TN) from diatom assemblages presented in the sediments from Little Round Lake, Ontario. These data were used in conjunction with historical land-use data in order to quantify the sequence and extent of nutrient enrichment related to human activity in the watershed area.  相似文献   

15.
The spatial and temporal distribution of planktonic, sediment-associated and epiphytic diatoms among 58 sites in Biscayne Bay, Florida was examined in order to identify diatom taxa indicative of different salinity and water quality conditions, geographic locations and habitat types. Assessments were made in contrasting wet and dry seasons in order to develop robust assessment models for salinity and water quality for this region. We found that diatom assemblages differed between nearshore and offshore locations, especially during the wet season when salinity and nutrient gradients were steepest. In the dry season, habitat structure was primary determinant of diatom assemblage composition. Among a suite of physicochemical variables, water depth and sediment total phosphorus (STP) were most strongly associated with diatom assemblage composition in the dry season, while salinity and water total phosphorus (TP) were more important in the wet season. We used indicator species analysis (ISA) to identify taxa that were most abundant and frequent at nearshore and offshore locations, in planktonic, epiphytic and benthic habitats and in contrasting salinity and water quality regimes. Because surface water concentrations of salts, total phosphorus, nitrogen (TN) and organic carbon (TOC) are partly controlled by water management in this region, diatom-based models were produced to infer these variables in modern and retrospective assessments of management-driven changes. Weighted averaging (WA) and weighted averaging partial least squares (WA-PLS) regressions produced reliable estimates of salinity, TP, TN and TOC from diatoms (r2 = 0.92, 0.77, 0.77 and 0.71, respectively). Because of their sensitivity to salinity, nutrient and TOC concentrations diatom assemblages should be useful in developing protective nutrient criteria for estuaries and coastal waters of Florida.  相似文献   

16.
Current bioassessment efforts are focused on small wadeable streams, at least partly because assessing ecological conditions in non-wadeable large rivers poses many additional challenges. In this study, we sampled 20 sites in each of seven large rivers in the Pacific Northwest, USA, to characterize variation of benthic diatom assemblages among and within rivers relative to environmental conditions. Analysis of similarity (ANOSIM) indicated that diatom assemblages were significantly different among all the seven rivers draining different ecoregions. Longitudinal patterns in diatom assemblages showed river-specific features. Bray–Curtis dissimilarity index values did not increase as a function of spatial distance among the sampled reaches within any river but the Malheur. Standardized Mantel r of association between assemblage similarity and spatial distance among sites ranged from a high of 0.69 (Malheur) to a low of 0.18 (Chehalis). In the Malheur River, % monoraphids, nitrogen-tolerant taxa, and beta-mesosaprobous taxa all decreased longitudinally while % motile taxa, especially Nitzschia, showed an opposite trend, reflecting a strong in-stream water quality gradient. Similar longitudinal trends in water quality were observed in other rivers but benthic diatom assemblages showed either weak response patterns or no patterns. Our study indicated that benthic diatom assemblages can clearly reflect among-river factors. The relationships between benthic diatom assemblages and water quality within each river may depend on the strength of the water quality gradients, interactive effects of water quality and habitat conditions, and diatom sampling design.  相似文献   

17.
To reconstruct sea‐level history from changes in tidal environments using diatom assemblages, we need to better understand the relations among brackish diatom assemblages and changing environments along elevational gradients from diverse coastal sites. Our statistical analysis reveals relations between environmental variables and brackish benthic diatom assemblages in the little studied region of south‐central Chile. Along four transects across salt marshes at two sites, we identified 224 diatom taxa in 112 samples. Detrended canonical correspondence analysis showed that tidal exposure time index and salinity were appropriately regressed against the abundance of diatom species using unimodal‐based methods. Our tests of classical and inverse regressions of weighted average and weighted averaging partial least squares (WA‐PLS) showed that WA‐PLS resulted in the highest coefficient of determination and the lowest root‐mean square of the error of prediction. Our regression will be useful in reconstructing environmental variables from fossil diatom assemblages in Chile.  相似文献   

18.
Monitoring changes in population levels of a wide range of species in biodiversity research and conservation requires practical, easy-to-use and efficient assessment and monitoring methods. Dragonflies (Insecta: Odonata) are a valuable tool for assessing aquatic systems and have been used as indicators of ecological health, ecological integrity, and environmental change, including climatic change, as well as indicators of habitat recovery. We field-tested a freshwater ecological integrity index, the Dragonfly Biotic Index (DBI), based on dragonfly assemblages at the local scale, and compared the DBI to a biodiversity index (average taxonomic distinctness, AvTD) as well as to a standard freshwater benthic macroinvertebrate-based freshwater health index (South African Scoring System, using Average Score Per Taxon, ASPT). We sampled 20 river sites, selected a priori. Adult dragonflies and benthic macroinvertebrates were collected using standardized methods. Environmental variables were collected in situ, and water samples taken. Temperature and pH were the most important physical environmental variables in explaining the assemblage structure, and we found significant abiotic–biotic relationships, as well as biotic–biotic relationships. Overall, dragonflies were more sensitive to changes in river condition than were macroinvertebrates, in part because they were responding at the species rather than higher taxonomic level. AvTD scores did not show any significant relationship with changes in river condition. Furthermore, sites with low biotic scores (indicating disturbance) had high AvTD values. In contrast, DBI site value and ASPT scores were highly significantly correlated. We conclude that dragonfly assemblages in the form of a DBI are an excellent tool for environmental assessment and monitoring freshwater biodiversity, with the potential to replace labour-intensive benthic macroinvertebrate-based freshwater quality assessments, such as SASS.  相似文献   

19.
Littoral benthic macroinvertebrates of 45 mountain lakes in the Tatra Mountains were sampled using a semi-quantitative method in September 2000. A total of 32,852 specimens were identified to 93 taxa belonging to 14 higher taxonomic groups. Multivariate statistics (CCA, RDA) and nine biotic metrics (AQEM/STAR) were used to explain relationships between macroinvertebrate assemblages and environmental variables. Up to 57% of the ecological position of littoral macroinvertebrate assemblages were explained by variance of environmental variables divided into chemical, trophic, physical, catchment and location. Five types of Tatra lakes were recognized using CCA: A — strongly acidified lakes (small catchment, low pH, high concentration of TP, DOC, highest amount of POM in littoral); B — alpine acidified lakes (low amount of POM, low values of biotic metrics); C — alpine non-acidified lakes (high value of diversity index, predominance of Diptera); D — subalpine acidified lakes (high values of biotic metrics: number of families, proportion of crenal and rhithral taxa/total taxa); E — subalpine non-acidified lakes (high values of biotic metrics: number of families, number of genera, BMWP score, number of taxa and abundance of EPT taxa). RDA was used to design five levels of macroinvertebrate taxa acidification tolerance. The Tatra Acidification Index (TAI) was established to assess the acidification status of the lakes in the Tatra Mts.  相似文献   

20.
城市溪流中径流式低坝对底栖动物群落结构的影响   总被引:2,自引:0,他引:2  
调查了浙江省安吉县内具径流式低坝的城市溪流(6个样点)和参照溪流(3个样点)的底栖动物群落,目的是了解城市溪流底栖动物群落结构退化规律和径流式低坝(2—3 m)对城市溪流底栖动物群落组成与结构的影响。结果表明,参照样点的底质组成以大石块(35.92%)和卵石(33.66%)为主,城市溪流以砾石为主(57.97%)。城市溪流水温和电导率显著高于参照溪流,TN和TP高于参照溪流。底栖动物总分类单元数和EPT分类单元数显著低于参照溪流。城市溪流河道内水坝上下游之间的流速(P=0.273)和宽深比(P=3.92)无显著差异。坝下游水体中的TP高于坝上游,电导率、溶解氧、pH值和水温在坝上下游之间几乎一致。除BI指数坝下游高于坝上游外,坝上下游间底栖动物总分类单元数、EPT分类单元数以及多样性指数、优势度和均匀度指数没有显著差异。但坝下游的耐污类群比例显著高于坝上游,敏感类群比例则显著低于坝上游。与坝上游相比,坝下游捕食者比例上升和集食者比例下降。NMDS结果进一步表明,城市溪流内水坝的建设导致坝上下游底栖动物群落物种组成明显改变。  相似文献   

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