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1.
The Nord/Pas-de-Calais region located in the North of France has been submitted, for several decades, to important pollution due to intensive industrialization. The present study reports on the effects of the metal and organic content of sediments in different streams on the benthic fauna, using multivariate analyses (PCA, CA, co-inertia analysis). Benthic macroinvertebrate communities present different assemblages along the Canal à Grand Gabarit and the river Aa, both in its natural and in its canalized stretches. These differences are more specifically due to anthropic factors such as the regulation of waterways and urban and industrial contamination. Co-inertia analysis enables to bring to the light the existence of a significant co-structure between environmental and faunistic data. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   

2.
贺湛斐  童春富 《生态学报》2023,43(11):4619-4631
太浦河连接东太湖和黄浦江,是东太湖向下游行洪的主河道,也是黄浦江上游重要的引水水源。分别于2017年10月、12月和2018年3月、6月在太浦河沿程设置的5个站点开展了大型底栖动物季节频次的取样调研,分析了太浦河大型底栖动物群落的结构特征及其主要影响因子。调查期间共采集到大型底栖动物25种,隶属于3门6纲14科,其中以河蚬(Corbicula fluminea)为代表的双壳类和以铜锈环棱螺(Bellamya aeruginosa)为代表的腹足类处优势地位。太浦河大型底栖动物群落的密度、生物量及多样性特征在不同站点间均存在显著差异(P<0.05);而在不同季节间均不存在显著差异(P>0.05)。聚类排序分析表明,太浦河大型底栖动物群落在空间上的差异较季节间的变化更为明显。太浦河大型底栖动物群落的物种组成特征与太浦河、东太湖的水文连通格局密切相关;而沿程不同程度人为干扰下的水体营养水平以及底质类型与生境异质性等生境条件对太浦河大型底栖动物群落的分布特征具有重要影响,其综合作用机理有待进一步研究。  相似文献   

3.
4.
巢湖流域水质生物学评价——以大型底栖动物为例   总被引:4,自引:0,他引:4  
由于长期暴露在自然环境中,底栖动物可整合不同时间尺度的物理、化学及生物信息,能反映污染物质对其造成的协同危害特征,因而被广泛应用于水体健康评价。为了弄清巢湖流域水体污染状况,于2009年4月对巢湖流域大型底栖动物进行采样调查。59个采样点中,鉴定出大型底栖动物共23种,其中:环节动物门6种,占26.1%;节肢动物门8种,占34.8%;软体动物门9种,占39.1%。尽管不同栖息环境中底栖动物的优势种有较大变化,但霍甫水丝蚓(Limnodrilus hoffmeisteri)、苏氏尾鳃蚓(Branchiura sowerbyi)和铜锈环棱螺(Bellamya aeruginosa)为整个巢湖流域优势物种。河流综合生物污染指数评价结果表明,巢湖流域水体均已受到不同程度的污染,南淝河的污染程度>白石山河>派河>巢湖湖体>柘皋河>杭埠河>裕溪河>丰乐河,这一结果与水质指标评价结果基本一致。  相似文献   

5.
1. Few studies have evaluated the effectiveness of riparian buffers in the tropics, despite their potential to reduce the impacts of deforestation on stream communities. We examined macroinvertebrate assemblages and stream habitat characteristics in small lowland streams in southeastern Costa Rica to assess the impacts of deforestation on benthic communities and the influence of riparian forest buffers on these effects. Three different stream reach types were compared in the study: (i) forested reference reaches, (ii) stream reaches adjacent to pasture with a riparian forest buffer at least 15 m in width on both banks and (iii) stream reaches adjacent to pasture without a riparian forest buffer. 2. Comparisons between forest and pasture reaches suggest that deforestation, even at a very local scale, can alter the taxonomic composition of benthic macroinvertebrate assemblages, reduce macroinvertebrate diversity and eliminate the most sensitive taxa. The presence of a riparian forest buffer appeared to significantly reduce the effects of deforestation on benthic communities, as macroinvertebrate diversity and assemblage structure in forest buffer reaches were generally very similar to those in forested reference reaches. One forest buffer reach was clearly an exception to this pattern, despite the presence of a wide riparian buffer. 3. The taxonomic structure of macroinvertebrate assemblages differed between pool and riffle habitats, but contrasts among the three reach types in our study were consistent across the two habitats. Differences among reach types also persisted across three sampling periods during our 15‐month study. 4. Among the environmental variables we measured, only stream water temperature varied significantly among reach types, but trends in periphyton abundance and stream sedimentation may have contributed to observed differences in macroinvertebrate assemblage structure. 5. Forest cover was high in all of our study catchments, and more research is needed to determine whether riparian forest buffers will sustain similar functions in more extensively deforested landscapes. Nevertheless, our results provide support for Costa Rican regulations protecting riparian forests and suggest that proper riparian management could significantly reduce the impacts of deforestation on benthic communities in tropical streams.  相似文献   

6.
Flow disturbances and conversions of land‐use types are two major factors that influence river ecosystems. However, few studies have considered their interactions and separated their individual effects on aquatic organisms. Using monthly monitoring data from two streams with different land‐use types (i.e. forest and agriculture) in the subtropical Central China over three years, we accurately predicted the changes of macroinvertebrate communities under flood disturbances and land‐use type conversions. The dominant taxa and main community metrics significantly declined following flash floods. Several mayflies and chironomid had rapid rates of recovery, which could reach high abundance in three months after floods. And most of the community metrics recovered more rapidly in the forested river than that in the agricultural river. Stepwise multiple regression (SMR) models were used to investigate the relationships between biotic metrics and hydrological and temporal variables. For example, SMR revealed that floods reduced the stability of benthic communities, and the length of low flow period was of considerable importance to the recovery of the fauna. Two‐way ANOVA indicated that intra‐annual fluctuation had more (e.g. the total abundance and wet biomass), equal (e.g. total richness, EPT richness, percent EPT abundance, and Margalef index), or less (e.g. tolerant value) influence on macroinvertebrate communities than land‐use types. Consequently, the effects of floods on macroinvertebrates should be taken into account when macroinvertebrates are used as indicators for assessing river ecosystem. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

7.
Conceptually, tolerance values represent the relative capacity of aquatic organisms to survive and reproduce in the presence of known levels of stressors. Operationally, they represent the relative abundance and co-location of organisms and stressors. These numeric values are then used for calculating tolerance metrics. Defensibility of biological assessments using tolerance metrics is compromised if the origins of the tolerance values or technical foundations of metrics are unknown. To minimize circularity and maximize objectivity, we define stressed conditions using physical and chemical factors. Also, since single, isolated stressors in stream systems are rare, we used an approach that combines multiple physical and chemical characteristics into a single general stressor gradient. In this paper, we describe development of tolerance values for benthic macroinvertebrate taxa collected from 455 wadeable stream sites throughout Mississippi, USA, except the Alluvial Plain. Principal components analysis (PCA) was used to develop a gradient that incorporated direct (instream physical and chemical) and indirect (land use) stressors, which was then scaled from 0 to 10. Weighted averaging of the relative abundance of each taxon was used to assign tolerance values based on the point of greatest relative abundance along the stressor gradient. Tolerance values were derived for 324 of the 567 taxa collected from the study sites, and primarily represented sensitivity to agricultural influences including degradation of physical habitat and nutrient enrichment, the dominant stressors within the state. We suggest that this approach could be used in other areas of the country to develop new tolerance values, refine existing ones, and may be a useful approach for other taxonomic groups.  相似文献   

8.
通过对滦河流域66个河段大型底栖动物采集和生境指标监测,基于大型底栖动物完整性评价和13种景观指数构建,探讨了不同景观指数对于大型底栖无脊椎动物完整性的解释能力。景观指数类型包括流域及欧式距离缓冲区土地利用百分比、水流路径缓冲区土地利用百分比、局部区域土地利用百分比和基于水流路径的反距离权重指数。基于多元线性逐步回归模型,根据调整R2(Square of the coefficient)来判断不同指数的解释能力。研究结果表明基于水流路径的反距离权重指数对于大型底栖动物完整性的解释能力最好,其次为基于水流路径的缓冲区和局部区域的土地利用百分比指数,全流域及欧氏距离缓冲区内土地利用百分比解释能力最差。农田是影响大型底栖动物完整性最重要的景观类型,距离河流越近的农田对大型底栖动物完整性的影响越大,因此流域及河岸带农田的控制和管理对于滦河流域大型底栖动物完整性的恢复具有重要的作用。  相似文献   

9.
Intensification of permafrost thaw has increased the frequency and magnitude of large permafrost slope disturbances (mega slumps) in glaciated terrain of northwestern Canada. Individual thermokarst disturbances up to 40 ha in area have made large volumes of previously frozen sediments available for leaching and transport to adjacent streams, significantly increasing sediment and solute loads in these systems. To test the effects of this climate‐sensitive disturbance regime on the ecology of Arctic streams, we explored the relationship between physical and chemical variables and benthic macroinvertebrate communities in disturbed and undisturbed stream reaches in the Peel Plateau, Northwest Territories, Canada. Highly disturbed and undisturbed stream reaches differed with respect to taxonomic composition and invertebrate abundance. Minimally disturbed reaches were not differentiated by these variables but rather were distributed along a disturbance gradient between highly disturbed and undisturbed sites. In particular, there was evidence of a strong negative relationship between macroinvertebrate abundance and total suspended solids, and a positive relationship between abundance and the distance from the disturbance. Increases in both sediments and nutrients appear to be the proximate cause of community differences in highly disturbed streams. Declines in macroinvertebrate abundance in response to slump activity have implications for the food webs of these systems, potentially leading to negative impacts on higher trophic levels, such as fish. Furthermore, the disturbance impacts on stream health can be expected to intensify as climate change increases the frequency and magnitude of thermokarst.  相似文献   

10.
盐沼植物对大型底栖动物群落的影响   总被引:4,自引:0,他引:4  
杨泽华  童春富  陆健健 《生态学报》2007,27(11):4387-4393
2005年5月下旬在崇明东滩中潮区相同高程上的裸地(ld)、海三棱藨草(Scirpus×mariqueter)地(hs)、芦苇(Phragmites australis)地(lw)、互花米草(Spartinaalterniflora)地(hh)里取样研究了大型底栖动物群落。ld物种数、总个体数、Shannon-Wiener指数、Margalef物种丰富度指数、平均密度和平均生物量都是最低的;平均密度在裸地和3种盐沼植物地间都存在显著差异(P<0.05,LSD检验);平均生物量在海三棱藨草地与裸地间存在极显著的差异(P<0.01,LSD检验);等级聚类分析(Cluster)表明,裸地和盐沼植物地间大型底栖动物群落差异明显。hs、lw、hh中的优势种都是底上附着型的软体动物,而ld中则以穴居型的甲壳动物占优势;hs、lw、hh、ld的面上群与面下群的比值分别为0.56、0.63、0.63、0.75。3种盐沼植物地间大型底栖动物群落相似性程度较高,但非度量多维标度(MDS)排序仍然揭示出可以区分的差异。这些差异体现了盐沼植物对大型底栖动物群落的明显影响。盐沼植物是通过直接改变生境结构或间接影响水动力和沉积物扰动等作用进而明显地影响大型底栖动物群落,盐沼植物也是影响潮间带大型底栖动物群落的重要生态因子。  相似文献   

11.
1. This study investigated the spatiotemporal dynamics of benthic invertebrate communities located close to the mouths of the Kalambo and Lunzua Rivers, at the southern end of Lake Tanganyika, and subject to varying degrees of sediment load. 2. Metrics of exposure to riverine sediments were associated inversely with abundance and diversity of benthic organisms at sampling locations adjacent to both river mouths, indicating a major effect of riverine sediments on the structure of near‐shore benthic communities. 3. A lower abundance of benthos was found at the mouth of the Lunzua River, which exports significantly higher sediment loads than the Kalambo. 4. Seasonal cycles of abundance and diversity in the benthos varied with distance from river mouths. This has important implications for monitoring programmes investigating benthic communities close to the mouths of rivers. 5. Our findings suggest that recent increases in the sediment loading of Lake Tanganyika, owing to anthropogenic catchment disturbance, impact significantly on biological diversity throughout the lake littoral, which provides habitat for the majority of species in the lake.  相似文献   

12.
海洋沉积物中重金属对底栖无脊椎动物的生物有效性   总被引:1,自引:0,他引:1  
汪飞  黄小平 《生态学杂志》2012,31(1):207-214
海洋沉积物是重金属的重要贮库,而海洋底栖无脊椎动物主要从沉积物中摄取重金属,这些被摄取的重金属能够通过食物链进行传递,进而影响到人类健康。本文总结了近些年来在海洋沉积物中重金属对底栖无脊椎动物生物有效性方面的研究进展,包括海洋底栖无脊椎动物对重金属的吸收途径、沉积物地球化学性质和底栖无脊椎动物生理等生物因素对沉积物中重金属生物有效性的影响。在此基础上,展望了未来研究重点,主要包括近海富营养化对沉积物中重金属生物有效性的影响,海洋底栖无脊椎动物消化道中的物理消化过程对沉积物中重金属生物有效性的影响,海洋底栖无脊椎动物整个生活史过程中沉积物中重金属生物有效性的变化等。  相似文献   

13.
The composition (% relative abundance) of diatom assemblages from soft bottom sediments was studied at 75 sites situated in 46 rivers, brooks, and ditches in the islands of Hiiumaa and Saaremaa and in the lowland of West Estonia. Although the total number of recorded taxa was 205, the studied diatom assemblages consisted of 54, 55, 48, and 50 constant species in the drainage basin of Moonsund, the Gulf of Riga, Hiiumaa, and Saaremaa, respectively. The habitats of the dominating taxa were heterogenous and the most widespread species were Achnanthidium minutissimum, Martyana martyi, Meridion circulare, Cocconeis placentula, Planothidium lanceolatum, and Amphora pediculus. The Shannon–Weaver diversity (H) index varied from 2.09 to 4.63. Multivariate analyses were used to identify the environmental variables governing the composition and structure of the benthic diatom assemblage. Principal Component Analysis (PCA) and Redundancy Analysis (RDA), based on 56 most abundant taxa, indicated differences in the composition and structure of diatom assemblages between different drainage basins as well as between the upper and lower stream courses. In the headwaters there prevailed small epipsammic diatoms (Martyana, Planothidium, Staurosira, Staurosirella). Different motile epipelic species from the genera Amphora, Navicula, Nitzschia, etc. were distributed abundantly in the lower courses of the streams. There was a positive correlation between order of the stream site and trophic level of water (R=0.35; p<0.05). Along a river system, the increasing order of the stream was accompanied by higher trophic level of water.  相似文献   

14.
李晋鹏  董世魁  彭明春  吴宣  周芳  于音 《生态学杂志》2017,28(12):4101-4108
底栖动物是对水生态系统退化和生境条件改变最为敏感的生物类群之一,同时也是开展梯级水坝水生态系统变化和演替研究的指示生物.本研究以国际生物多样性保护及水电梯级开发生态影响研究的热点地区澜沧江中下游为例,以澜沧江干流兴建的第一座水坝漫湾库区为研究区域,分别于2011和2016年开展底栖动物定点采样,并结合其蓄水前(自然河段,1996年)和单级水坝蓄水初期(1997年)的历史调研数据,全面分析了梯级水坝运行前后漫湾库区底栖动物群落的结构、分布格局及演变趋势.结果表明: 漫湾库区底栖动物群落的优势种组成逐渐由寡毛纲和昆虫纲种类演变为软体动物门类占绝对优势;沿库区生境的纵向梯度变化,底栖动物密度和生物量均表现为升高的趋势,而静水区增加更为显著;对底栖动物功能摄食群的分析表明,静水区由掠食者和收集者占优势演变为滤食者类占绝对优势;梯级水坝运行后,采用生物指数评价结果表明,2016年库区综合水质指标明显优于2011年.漫湾库区底栖动物群落的演变与上游梯级小湾水坝的调度运行及库区的水文状况和泥沙淤积情况密切相关,并随着梯级水坝的运行处于动态变化之中.  相似文献   

15.
王璐  杨海军  李玲  南晓飞  张振兴  李昆 《生态学杂志》2017,28(11):3775-3783
长白山森林源头溪流每年11月至次年4月有约70%的河面被冰覆盖,季节性冻融过程特征明显.为了揭示溪流冻结初期凋落叶分解与底栖动物定殖的关系,在长白山地区1条源头溪流中,利用2种孔径(5和0.3 mm)的尼龙分解袋对色木槭、紫椴、蒙古栎的单一及混合凋落叶进行了为期35 d的分解研究.结果表明: 凋落叶质量损失率在单一树种间差异显著,表现为:色木槭>紫椴>蒙古栎,而在4种混合凋落叶间差异不显著;除紫椴和3树种混合凋落叶外,粗、细分解袋间凋落叶质量损失率差异不显著;凋落叶混合效应仅出现在紫椴-蒙古栎混合的粗分解袋内;定殖在不同凋落叶分解袋内的底栖动物群落结构差异较大,但撕食者密度在3种凋落叶间差异不显著,撕食者对凋落叶混合效应的响应也不显著.由结果可知,溪流冻结初期微生物是凋落叶的主要分解者,底栖动物的贡献率较低.虽然撕食者密度较低,但撕食者的活动是凋落叶混合效应出现的必要条件.底栖动物对食物和栖息地有一定的选择性,但由于定殖时间较短,凋落叶对撕食者定殖的影响不显著.本研究对源头溪流生态系统的冬季生态过程研究及生态系统管理具有一定的理论意义.  相似文献   

16.
【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   

17.
水体富营养化是一个全球性的问题,中国也面临严重威胁.目前,中国的水体富营养化研究主要集中在湖泊和水库,对河流的研究极少.根据大型底栖无脊椎动物的群落结构对营养盐胁迫的响应,运用非参数转变点分析方法计算西苕溪上游营养盐浓度突变点.结果表明:总氮和总磷的突变点分别为1.409mg·mL-1和0.033~0.035mg·mL-1.参照点的总氮和总磷浓度基本都低于阈值,城市干扰点则全部高于阈值,而当总氮和总磷超过各自阈值时会导致大型底栖无脊椎动物群落结构的严重退化.通过建立与水生生物群落结构有关的水体营养盐标准,可充分发挥生物监测在水环境管理中的作用,为计算水体中总氮和总磷的最大日负荷总量提供科学数据.  相似文献   

18.
流溪河大型底栖动物群落的时空分布及其影响因子   总被引:1,自引:0,他引:1  
流溪河位于我国热带与亚热带过渡区,其底栖动物种类丰富,群落的物种组成结构具有明显的区域性,掌握该地区的物种组成特征及与环境要素的关系是建立生态监测与评估方法的基础。于2018年的枯水期(3月、12月)和丰水期(6月、9月),自流溪河上游至下游共计20个段面对底栖动物进行了定量采样,同时测定了相应的环境因子,采用多元统计方法对流溪河水环境与群落结构及其相关关系进行了分析。共检出底栖动物76个分类单元,隶属于7纲20目50科,其中水生昆虫相对丰度最高,占69.39%。在4个优势分类单元中,摇蚊族(Chironomini)相对丰度为20.19%,河蚬(Corbicula fluminea)、短沟蜷属的一种(Semisulcospira sp.1)、双突细蜉(Caenis bicornis),相对丰度在7%-9%之间。底栖动物丰度和种类多样性均与浊度呈显著负相关;枯水期底栖动物丰度与总磷呈显著负相关,丰水期则呈显著正相关。在丰水期,不同河流级别上底栖动物群落具有明显的差异,表现较强的分布格局,而在枯水期这种分布格局不明显。典范对应分析(CCA)表明,在丰水期,影响或解释流溪河底栖动物群落变化的主要因子为pH、溶解氧、水温、电导率和硅酸盐,而在枯水期则为pH和硝态氮。受电站与采沙的影响,部分河段发生非自然断流和底质的显著改变,导致底质与水深等数据的异常变化,反映了人类活动对该河流生境与环境的重要影响。  相似文献   

19.
From December 1996 to August 1997, beech litter breakdown and stream benthic macroinvertebrate communities were investigated to assess the effects of acidic precipitation on community structure and function in two second-order headwater streams of the Vosges Mountains (NE France). Because of microscale changes in bedrock mineral composition, one of the streams was acidified (mean pH=4.53, mean total Al=421 g.l-1) and the other circum-neutral (mean pH=7.23, mean total Al=36 g.l-1). Results showed that both litter breakdown rate and macroinvertebrate community structure were drastically affected under acidic conditions. The rate of leaf litter breakdown decreased by nine times in the acidic stream. Benthic sampling showed that scrapers were totally eradicated and both gathering and filtering collectors were drastically reduced. Such drastic effects appear to be the consequences of the toxicity of acid water including both proton and aluminum toxicity. A decrease in shredder abundance and a shift from the efficient acid-sensitive Amphipoda Gammarus fossarum to acid-tolerant Nemouroidea (mainly Leuctra sp.) was observed in the acidic stream. Our results indicate that freshwater acidification significantly alters the action of shredders processing leaf litter in the acidic stream. Consequently, interactions between structural and functional responses to acidification probably have profound consequences on the efficiency of acidified stream ecosystems, which in return may alter downstream functioning.  相似文献   

20.
A total of 76 taxa of benthic macroinvertebrates as collected from Ham's Lake, Oklahoma, during 1974 and 1975. The composition and density of the benthic assemblage was similar to that of other Oklahoma reservoirs. The number of species and density of macroinvertebrates decreased from March to the end of July, 1975 Species diversity and biomass did not change significantly with time. Number of species and species diversity decreased with depth on all sampling periods. The most pronounced changes occurred between 4 and 5 m during periods of thermal stratification and hypolimnion anoxia. Artificial destratification removed the thermocline from Ham's Lake within 2 wk. More gradually, the deep waters were reoxygenated. Destratification did not substantially alter the depth distribution of benthic macroinvertebrates until oxygen level of the deep water was increased. Research supported with funds from the Oklahoma Water Resources Research Institute and the Bureau of Reclamation.  相似文献   

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