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1.
三峡库区不同水文类型支流大型底栖动物对蓄水的响应   总被引:1,自引:0,他引:1  
为探究三峡水库修建对库区不同水文类型支流大型底栖动物的影响,于2015年7月和2016年1月对三峡水库四条支流的大型底栖动物进行调研,分别对周期性受蓄水影响支流的非回水区与回水区和长期受蓄水影响支流的非回水区与回水区大型底栖动物群落结构进行比较研究,结果表明:⑴7月份三峡水库145米低水位时期共采集到底栖动物655头计59种(属),在受蓄水影响河段采集到底栖动物4种共40头,优势种为日本沼虾(占受蓄水影响区域的57.5%); 1月份三峡水库175米蓄水时期共采集到底栖动物1123头计69种(属),在受蓄水影响河段采集到16种238头,优势种为锯齿新米虾(占受蓄水影响区域的14.2%)。⑵周期性受蓄水影响支流的非回水区与回水区底栖动物密度、生物量和多样性指数无显著差异(P0.05);长期受蓄水影响支流的非回水区与回水区之间底栖动物密度和Pielou均匀度指数无显著差异(P0.05),但非回水区底栖动物生物量显著高于回水区(P0.05),底栖动物多样性和丰富度极显著高于回水区(P0.01)。⑶7月份影响底栖动物分布的主要环境因子共6个,分别是水深、流速、硝态氮、溶解氧、水温和电导率; 1月份影响底栖动物分布的主要环境因子共7个,分别是水温、溶解氧、总磷、流速、深度、电导率和透明度。  相似文献   

2.
Biodiversity of constructed wetlands for wastewater treatment   总被引:3,自引:0,他引:3  
Constructed wetlands are often built for wastewater treatment to mitigate the adverse effects of organic pollution in streams and rivers caused by inputs of municipal wastewater. However, there has been little analysis of biodiversity and related factors influencing the ecosystem functioning of constructed wetlands. The purpose of this study was to evaluate the biodiversity of two free-water-surface integrated constructed wetlands in subtropical Taiwan by analyzing the water quality, habitat characteristics, and biotic communities of algae, macrophytes, birds, fish, and aquatic macroinvertebrates in the treatment cells. Our results indicated that the two integrated constructed wetlands (Hsin-Hai II and Daniaopi Constructed Wetlands) achieved good performance in reducing the concentrations of total nitrogen (TN) and total phosphorus (TP), and loadings of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) from municipal sewage. In total, 58 bird species, 7 fish species, and 34 aquatic macroinvertebrate taxa were recorded in the two wetlands. The results of stepwise multiple regressions showed that the richness, abundance, and diversity of birds increased with wetland area. Fish richness and abundance respectively increased with wetland area and dissolved oxygen, while the diversity decreased with increases in TP concentrations. The richness and density of aquatic macroinvertebrates increased with the cover of aquatic macrophytes, while the diversity increased with wetland area. Ordination analyses indicated that variations in the community structures of birds, fishes, and aquatic macroinvertebrates were respectively best explained by water temperature, wetland area, and species richness of fish. Our results suggest that wetland area, cover of aquatic macrophytes, and water quality were the most important factors governing the diversity in the constructed wetlands, and that the factors influencing community structures varied among different taxonomic groups. In addition to improving water quality, this study implied that the biodiversity of constructed wetlands for wastewater treatment can be enhanced through proper design and management.  相似文献   

3.
Summary The longitudinal distribution of macroinvertebrates and fish in a lower Niger delta river (R. Sombreiro) was studied from November 1979 to June 1982.When combined with an earlier study on the physico-chemical features of the river (NWADIARO, 1984), two zones could be discerned. These are (a) an upstream, soft, acid freshwater reach, approximately 86 km long, inhabited mainly by insects, with the dwarf cichlid fishPelvicachromis/Chromidotilapia complex as the distinctive fish type and (b) a downstream, hard, neutral to slightly alkaline brackish water zone, about 30 km long, populated mainly by Crustacea (shrimps and crabs) and molluscs, withMonodactylus sebae as the characteristic fish.The diversity of macroinvertebrates and fish in the upstream zone was togher than in the downstream zone.  相似文献   

4.
Changes in species composition and diversity of benthic macroinvertebrates during summer and fall were compared in an area of a lake artificially destratified and in an arm not destratified. Numbers of species, diversity, and density were significantly correlated with the concentration of dissolved oxygen, while none of the biotic variables were correlated with temperature.Research supported with funds from the Oklahoma Water Resources Research Institute  相似文献   

5.
The concept of spatial scale is at the research frontier in ecology, and although focus has been placed on trying to determine the role of spatial scale in structuring communities, there still is a further need to standardize which organism groups are to be used at which scale and under which circumstances in environmental assessment. This paper contributes to the understanding of the variability at different spatial scales (reach, stream, river basin) of metrics characterizing communities of different biological quality elements (macrophytes, fishes, macroinvertebrates and benthic diatoms) as defined by the Water Framework Directive. For this purpose, high-quality reaches from medium-sized lowland streams of Latvia, Ecoregion 15 (Baltic) were sampled using a nested hierarchical sampling design: (river basin → stream → reach). The variability of metrics within the different groups of biological quality elements confirmed that large-bodied organisms (macrophytes and fish) were less variable than small-bodied organisms (macroinvertebrates and benthic diatoms) at reach, stream and river basin scales. Single metrics of biological quality elements had the largest variation at the reach scale compared with stream and basin scales. There were no significant correlations between biodiversity indices of the different organism groups. The correlation between diversity indices (Shannon’s and Simpson’s) of the biological quality elements (macrophytes, fish, benthic macroinvertebrates and benthic diatoms) and a number of measured environmental variables varied among the different organism groups. Relationships between diversity indices and environmental factors were established for all groups of biological quality elements. Our results showed that metrics of macrophytes and fish could be used for assessing ecological quality at the river basin scale, whereas metrics of macroinvertebrates and benthic diatoms were most appropriate at a smaller scale.  相似文献   

6.
A field experiment was conducted to examine the influence of variable density (complexity) of small patches of woody debris on the abundance and taxonomic richness of macroinvertebrates and fishes in the Brazos River, a meandering lowland river in east-central Texas. Woody debris patches contained bundles of either 8 or 16 sticks of two sizes, and reference plots contained no woody debris. The experiment was conducted in the littoral zone in the river channel and a nearby oxbow lake. Organisms were collected from each patch after 14 days. Abundance and taxonomic assemblage structure of macroinvertebrates in both the river channel and oxbow were significantly and positively influenced by complexity of woody debris. For fish in the oxbow, abundance and species richness were greater in woody debris than sites lacking structure, but the opposite trend was observed for fish in the river channel. This difference could be associated with isolation from source habitats and low colonization of the constructed woody debris patches in the river by fishes with affinities for complex habitats. Small lotic-adapted minnows were captured from reference habitats in the channel, but these species were rare in woody debris patches. This was in contrast to aquatic insects in the river channel, such as caddisfly and midge larvae, that efficiently colonized the small isolated patches of woody debris. In a lotic environment, woody debris provides vertical surfaces that intercept drifting insect larvae and provides protection from the water current. We speculate that greater abundance of macroinvertebrates in woody debris patches in both habitats results from the combined influence of high food resource availability and refuge from predation provided by structurally complex habitats. Handling editor: R. Bailey  相似文献   

7.
Meanders are complex aquatic environments exhibiting different flow and sediment characteristics that influence macroinvertebrate distribution. Differences in macroinvertebrate composition, freshwater mussel density (mainly Castalia ambigua Lamarck, 1819) and habitat variables were investigated, using uni‐ and multivariate analyses, in two zones, the margin and thalweg, of the meanders of a 7‐km stretch of a morphologically unaltered tropical alluvial lowland river. Clear differences were found between meander zones, with greater taxonomic and functional diversity of macroinvertebrates and greater freshwater mussel densities in the meander margin. A total of 12 families of macroinvertebrates were exclusive to the meander margin, and macroinvertebrate indicators of zones were Philopotamidae and Leptoceridae (meander margin) and Chironomidae and Elmidae (meander thalweg). In the meander margin, there were no differences in macroinvertebrate abundance, and taxonomic and functional group diversity among areas with low, medium and high mussel density. Macroinvertebrate abundance did not vary between zones, but in both, abundance was associated with lower pH and higher electrical conductivity. Low shear velocity, which stabilises the river bed, high organic matter content and percentage silt in the meander margin were associated with higher taxonomic and functional macroinvertebrate diversity, as well as the presence of freshwater mussels. Natural unaltered meanders are spatially heterogeneous in both habitat and biodiversity and, similar to restored meanders, support greater macroinvertebrate taxonomic and functional diversity, as well as maintain freshwater mussel beds, mainly by stabilising the river bed. The meander margin may also be important for attracting mussel host fish that feed on macroinvertebrates and aid mussel dispersal. Thus, the meander margins, and other similar riparian habitats with low shear velocity, for example, side channels and pools, have potentially high conservation value and should be afforded due protection.  相似文献   

8.
In this research, structural and functional responses of benthic macroinvertebrates to mitigation measures (carried out in the dammed and polluted Duraton River, Central Spain, during the 1990s and 2000s) were examined by comparing physicochemical and biological data from the summer of 1987 with data from the summer of 2014. Mitigation measures resulted in significant increases in dissolved oxygen concentrations, as well as in significant reductions of fluoride (F) pollution and short-term flow fluctuations. The macrobenthic community responded positively to improvements in river environmental conditions, exhibiting significant increases in abundance (total density, total biomass and EPT density) and diversity (total family richness and EPT richness) at impacted sampling sites. Furthermore, the presence of relatively sensitive benthic macroinvertebrates after mitigation measures (as indicated by increased values of BMWQ biotic indices) also was the main cause for observed reductions in the environmental impact caused by disturbance points (as indicated by decreased values of the EI index), and for the observed recovering of the trophic structure of the macrobenthic community, with macroinvertebrate scrapers as the functional feeding group most favored. These macroinvertebrate responses to mitigation measures were more marked at sampling sites that initially were more impacted (i.e., nearest to disturbance points), and less apparent at the sampling site that initially was less impacted (i.e., farthest to disturbance points). Within the hydropsychid assemblage, improvements in river environmental conditions clearly favored the presence of Hydropsyche pellucidula and Cheumatopsyche lepida at the expense of the other hydropsychid species. In spite of all monitored environmental improvements and macroinvertebrate positive responses, the need for additional mitigation measures was evident, particularly to reduce high turbidity levels and sedimentation of fine inorganic matter negatively affecting benthic macroinvertebrates downstream from the industrial effluent. Overall, it is concluded that the multimetric approach is an effective technique to assess macroinvertebrate responses to mitigation measures in river ecosystems.  相似文献   

9.
The river Woluwe in Brussels and Flanders (Belgium) is a small tributary of 15 km length that drains an area of 9400 ha in the Schelde river basin. The headwaters of the Woluwe are highly fragmented by diverse pond systems and are vaulted in the Brussels agglomeration. Hyporheic zones locally influence the water quality. The downstream stretch of the river receives sewage waters from households and industry. As the river Woluwe within a short distance represents a typical gradient from groundwater-fed sources in the forest towards severely polluted water, a comparative monitoring using diatoms, macroinvertebrates and macrophytes was done. The saprobic index based on diatoms, the Belgian Biotic Index (BBI) for macroinvertebrates and a macrophyte index based on the N-values of Ellenberg were used in this comparison and for estimating the correlation with the bimonthly measured chemical variables in 16 sampling stations. The diatom saprobic index and the macrophyte index were strongly correlated. Both groups showed strong correlations with phosphate, ammonium and chemical oxygen demand. The Belgian Biotic Index showed lower correlations with the nutrient variables, but was slightly better correlated to chemical oxygen demand, chloride and dissolved oxygen. None of the indices showed a correlation with nitrate. Local substrate or light conditions could interfere with the indicator system, especially for the macrophytes and occasionally for the macroinvertebrates. It was concluded that at least in this particular river system, the indices based on the primary producers were more indicative for the trophic status, whereas the BBI showed a broader relationship to the general degree of pollution. Therefore, these three indices are considered as complementary for monitoring the biological quality and the ecological status of a river system.  相似文献   

10.
The effects of introducing a zooplanktivorous fish, three-spined stickleback, (Gasterosteus aculeatus) and a benthivorous fish, tench (Tinca tinca) separately and in combination to replicated experimental enclosures with two density levels of white water lily (Nymphaea alba) were studied in Little Mere, UK. Numbers of Daphnia hyalina were high and only slightly diminished at reduced lily densities, probably due to stickleback predation, but there was no consequential effect on phytoplanktonic chlorophyll a concentrations. Tench reduced the numbers of gastropods but not of other macroinvertebrates, and in turn increased the biomass of periphyton growing on artificial substrata within the enclosures. The higher lily density reduced oxygen concentrations and pH values and increased total phosphorus and soluble reactive phosphorus concentrations but otherwise had little effect on water chemistry. There was little interactive effect of the fish species. The results are integrated with those of six other such enclosure experiments carried out in Little Mere since 1992.  相似文献   

11.
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   

12.
Mediterranean streams are characterised by seasonal droughts, the frequency and intensity of which vary spatially and are expected to increase with global change. We studied the potential effects of drought and climate change on the fish assemblage and its trophic ecology in a Mediterranean stream by comparing an intermittent tributary with two more permanent neighbouring reaches. Although the three sites were dominated by the same two fish species, Mediterranean barbel (Barbus meridionalis) and chub (Squalius laietanus), the intermittent tributary had a lower overall fish density and fewer eel (Anguilla anguilla). The intermittent tributary had macroinvertebrates with lower density, smaller taxa and higher diversity. Fish in the intermittent tributary had significantly lower biomasses in their gut contents (adjusted for fish length) and more negative electivities than those in the permanent reaches, as well as significantly lower taxonomic diversity. These results indicate that there was reduced resource availability in the intermittent tributary, which resulted in significantly lower condition and gonadal weight (adjusted for length) of barbel and chub. The data obtained in this Mediterranean stream support the observation that reduced water flow may affect fish at both individual and assemblage levels.  相似文献   

13.

In recent decades, the Eurasian beaver (Castor fiber) has once again become the keystone species in small river ecosystems in Russia. In many places, beaver activity has resulted in a significant change in lotic habitats, affecting the diversity, density, and biomass of aquatic organisms, including fish. While many studies have considered the ecosystem impacts of beavers, relatively few have focused on understanding the influence of beaver activity on steppe rivers. We conducted the first quantitative study of beaver impacts on fish assemblages in beaver-influenced and beaver-free sites on two small steppe rivers in the Don River basin in Russia. The presence of beavers altered the habitats in small steppe rivers and affected the diversity, density, and biomass of fish. A comparison of the number of species, density, and biomass of fish in six types of river habitats showed that these parameters were lower in beaver ponds than at riverine sites without beaver activity. Three fish species primarily preferred a single habitat type. Barbatula barbatula was found in riffles, Misgurnus fossilis in old beaver ponds, and Eudontomyzon mariae in abandoned beaver ponds. Beavers impacted fish distribution and density by changing dissolved oxygen, pH, and water current velocity. Overall, our results showed that the presence of beavers led to a temporary homogenization of fish habitats at a local scale in the valleys of small steppe rivers because beavers occupied these rivers only for a short period. However, habitat heterogeneity may increase if the beaver population stays stable or expands in the future.

  相似文献   

14.
Studies of trophic networks and the evaluation of processes that occur along altitudinal gradients in river systems are of great importance because they allow an understanding of energy flow dynamics and provide scientific tools for the planning and management of river ecosystems. This research describes the trophic network of aquatic macroinvertebrates along an altitudinal gradient of the Gaira River, a mountain Neotropical watercourse located in the Sierra Nevada de Santa Marta in northern Colombia. The organisms were collected in the upper, middle and lower reaches of the river during the rainy and dry seasons (between 2010 and 2013). Trophic relationships were evaluated through gut content analysis. The contents were determined and quantified using photographs and expert review, and a binary consumption matrix was used to determine the characteristics of the trophic network. We characterized the diet composition at each site for each season using discriminant analysis. Trophic networks during the dry seasons showed higher trophic species richness and linkage density, and the predominance of coarse particulate organic matter (CPOM) and fine particulate organic matter (FPOM) in the high and medium sections of the river. During the dry seasons the diets had a lower number of basal species, but in the low river section there was a high percentage of fungi and microalgae. During the rainy seasons, no patterns were observed for the percentage of resources. Results indicated a direct relation between periods of hydrologic stability and an increase of CPOM during dry seasons and an increase of resource diversity consumed by macroinvertebrates at all sites during the rainy season, showing that changes in trophic networks of the Gaira River were more important during seasonal periods than along the altitudinal gradient.  相似文献   

15.
屈霄  刘晗  阳敏  辛未  王伟民  陈宇顺 《生态学报》2022,42(24):10029-10040
理解城镇的快速发展对河流鱼类群落结构的影响,是城镇河流科学管理和生物多样性保护的关键基础。本研究于2019年丰水期(8月)和枯水期(11月),选取我国城镇化典型城市-深圳域内两个处于不同城镇化程度的代表性流域,应用多重统计方法比较分析了流域间鱼类群落结构的差异,并探讨了驱动鱼类群落变异的关键环境要素。结果发现,城镇化程度高的观澜河流域其鱼类种类组成、优势类群、生物多样性指数与城镇化程度低的坪山河流域有明显差别。 具体表现为:城镇化程度高的流域土著敏感种类如异鱲、吸鳅等几近消失,优势类群为外来入侵耐受种类,其物种多样性显著低于城镇化程度低的流域(P<0.05)。同时,外来鱼类在城镇河段其数量占比平均达92.5%,广泛分布于深圳城镇河流中。在环境因素方面,城镇化程度高的观澜河流域水体理化指标总氮、总磷、氨氮、化学需氧量、生化需氧量、高锰酸盐指数均显著性高于城镇化程度低的坪山河流域(P<0.05)。基于Bray-Curtis距离的冗余分析显示:城镇用地占比和总氮是影响观澜河和坪山河流域鱼类群落差异的主要因素。城镇化进程中河流生境的改变已影响到土著鱼类的生物多样性。因此,推动以恢复土著鱼类生物多样性的河流生态治理与保护是今后水生态目标管理的重要方向。  相似文献   

16.
研究河流生境时空变化对大型底栖动物功能摄食类群的影响,分析底栖动物功能摄食类群对环境因子的响应关系,对评估河流生态系统健康具有重要意义。以长江支流桥边河为研究对象,基于2020年8月、2021年1月和2021年4月对桥边河大型底栖动物和水体理化因子的调查数据,分析了大型底栖动物功能摄食类群的构成以及时空分布特征。结果表明:共采集到大型底栖动物3门38种,包括节肢动物门23种、软体动物门13种、环节动物门2种。桥边河大型底栖动物功能摄食类群中滤食者占绝对优势,其次为刮食者、捕食者、撕食者和收集者。滤食者的优势种为闪蚬和河蚬,刮食者的优势种为方格短沟蜷、铜锈环棱螺和卵萝卜螺,捕食者的优势种为河蟌,撕食者的优势种为秀丽白虾,收集者的优势种为黄色羽摇蚊。冗余分析(RDA)表明,影响桥边河大型底栖动物功能摄食类群的主要环境因子为溶解氧(DO)、氨态氮(NH4+-N)、水深(Dep)、pH、温度(T)和硝态氮(NO3--N)。研究大型底栖动物功能摄食类群组成和时空分布特征,可为河流生态系统修复提供参考依据。  相似文献   

17.
Biomass and species diversity (richness and evenness) of littoral organisms were explored in 27 sites in three basins of the large Lake Saimaa system in eastern Finland. The basins differed in degree of nutrient loading and trophic status. Six organismal groups, i.e., phytoplankton, periphyton, macrophytes, crustacean zooplankton, benthic macroinvertebrates and fish were studied. Factors affecting the biomass and diversity of these groups were explored by multiple stepwise regression analysis. The biomass of different groups was explained by the same variables, mainly nutrients, while diversity was associated with different environmental factors among the studied groups. The biomass of periphyton, phytoplankton, zooplankton, and fish correlated significantly with each other. There was also an apparent association between the biomass of macrophytes and that of benthic invertebrates. However, no significant correlations were found among the diversity of the studied groups. In accordance with previous studies, our results did not support the existence of species-rich hotspots or the possibility of using any surrogate taxon to reveal overall biodiversity. Thus, for conservation planning, biological surveys should include extensive collection of taxonomic groups and organisms at all trophic levels.  相似文献   

18.
刘麟菲  谭冰冰  殷旭旺  张远  孟伟 《生态学报》2014,34(22):6613-6621
2009年8—9月,对辽宁省太子河流域67个点位进行采样调查,以硅藻群落为研究对象,比较硅藻属级水平与种级水平相对多度、物种丰富度以及生物多样性指数间的相关性,并比较硅藻属级与种级属性与环境因子的相关性。实验结果表明,太子河流域硅藻属级水平的相对多度、丰富度和多样性指数与硅藻种级水平都极显著相关。Pearson相关性分析表明,硅藻属级水平的丰富度与环境显著相关的因子与种级水平丰富度与环境显著相关的因子相一致。Mantel-Test相关性分析表明,硅藻属级水平的相对多度与环境因子的相关性弱于种级水平与环境因子相关性。典范对应分析结果显示,影响硅藻属级和种级群落结构分布的主要环境因子均为悬浮物。基于硅藻生物评价指数的流域健康评价结果表明,应用硅藻属级和种级属性对太子河流域进行健康评价,其评价结果相一致。  相似文献   

19.
Authors index     
Darrigran  Gustavo  Martin  Stella M.  Gullo  Bettina  Armendariz  Laura 《Hydrobiologia》1998,367(1-3):223-230
An analysis was made of specific richness (S), specific diversity (H), equitability (J), frequency (F), dominance (Dm) and density (D) of the macroinvertebrates associated with the invasive species Limnoperna fortunei (Dunker, 1857), was made. Limnoperna fortunei caused an increase in the specimen number on the rocky environment studied. The species richness and abundance of different taxa of macroinvertebrates, except mollusks was positively related to the presence and density of L.fortunei. Autochthonous gastropod species conversely, tended to be displaced. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
雅鲁藏布江流域底栖动物多样性及生态评价   总被引:4,自引:0,他引:4  
雅鲁藏布江起源于喜马拉雅山,是世界上海拔最高的河流之一,是流经我国西藏境内重要的国际河流,其河流生态系统具有特殊地貌及生态条件。研究该流域底栖动物多样性分布特征及其影响因子,是科学评价该区域河流生态系统健康状况,实现资源可持续开发利用的基础。2009年10月—2010年6月期间,以底栖动物作为指示物种,对雅江流域干支流及堰塞湖的14个采样断面进行河流生态评价。采用Alpha及Beta生物多样性指数分别指示局部采样河段及全区域的底栖动物多样性。对采样断面底栖动物组成分析发现:14个采样断面共采集到底栖动物110种,隶属57科102属。雅江干流底栖动物种类数最高为29,平均为19。支流年楚河种类数为17。支流拉萨河,尼洋河,帕龙藏布的最高种类数分别为25,33,36;平均种类数分别为21,21,22,生物多样性普遍高于干流。整个流域中底栖动物平均种类数相差不大,但种类组成和密度相差较大。调查区域的Beta多样性指数β高于低海拔地区的相似的山区河流,说明雅江流域内底栖动物群落差异性高于正常海拔地区。对14个采样断面的物种组成进行除趋势对应分析表明:影响雅江流域底栖动物多样性的主要因素为河型,河床阻力结构,堤岸结构,水流流速。保持稳定的阶梯-深潭结构和自然堤岸结构,以及适宜的流速有利于保护雅江河流生态。  相似文献   

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