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1.
基于河流网络体尺度的皖河河源溪流鱼类群落的空间格局 总被引：2，自引：0，他引：2
2013年7-8月对大别山皖河河源1～3级溪流的鱼类进行了调查,着重从河流网络体空间尺度研究了鱼类多样性及群落结构的空间格局,探讨了局域栖息地条件和支流空间位置对鱼类群落的影响.1～3级溪流间,鱼类物种数随溪流级别增大显著增多,但个体数无显著变化(P＞0.05);长河、潜水和皖水3条支流间鱼类物种数和个体数均无显著差异(P＞0.05).鱼类物种数受局域栖息地条件(海拔)和支流空间位置(河流级别和下游量级)的联合影响,但鱼类个体数仅受局域栖息地条件(海拔)的影响.不同溪流级别和不同支流间的群落结构均无显著差异(P＞0.05).同物种数类似,鱼类群落结构也受局域过程(海拔)和空间过程(汇合量级和下游量级)的联合影响.本研究表明,总体上皖河河源溪流网络体中的鱼类群落是局域过程和空间过程联合作用的产物.因此,为合理保护和管理皖河河源的溪流鱼类物种,有必要兼顾局域栖息地条件与河流网络连通性的保护和恢复. 相似文献
2.
Pander J, Geist J. Seasonal and spatial bank habitat use by fish in highly altered rivers – a comparison of four different restoration measures.
Ecology of Freshwater Fish 2010: 19: 127–138. © 2009 John Wiley & Sons A/S
Abstract – River regulations have resulted in substantial modifications of the characteristics and the diversity of stream ecosystems. Fish habitat use in the context of species life histories and temporal habitat dynamics are crucial for the development of sustainable measures of habitat restoration in degraded rivers. The objective of this study was to compare the effects of introducing four different in-stream structures (bank ripp-rapp, benched bank ripp-rapp, successively grown riparian wood and artificial dead wood, nine replicates each) on the seasonal fish community distribution in a heavily modified stream ecosystem. Species richness and diversity, fish biomass and density showed strong variation (i) between habitat types, (ii) among replicates of the same habitat type, and (iii) in different seasons. The current low abundance of historical widespread rheophilic and migratory fish species in the study stream suggests that technical bank habitat restoration measures are only of limited use for the restoration of highly specialised target species in conservation such as Barbus barbus and Chondrostoma nasus . However, introduction of particular artificial stream structures (in particular of artificial dead-wood fascines) was found to concentrate biomass and density of none-specialised fish species like Squalius cephalus , Alburnus alburnus , Gobio gobio or Rutilus rutilus . 相似文献
Ecology of Freshwater Fish 2010: 19: 127–138. © 2009 John Wiley & Sons A/S
Abstract – River regulations have resulted in substantial modifications of the characteristics and the diversity of stream ecosystems. Fish habitat use in the context of species life histories and temporal habitat dynamics are crucial for the development of sustainable measures of habitat restoration in degraded rivers. The objective of this study was to compare the effects of introducing four different in-stream structures (bank ripp-rapp, benched bank ripp-rapp, successively grown riparian wood and artificial dead wood, nine replicates each) on the seasonal fish community distribution in a heavily modified stream ecosystem. Species richness and diversity, fish biomass and density showed strong variation (i) between habitat types, (ii) among replicates of the same habitat type, and (iii) in different seasons. The current low abundance of historical widespread rheophilic and migratory fish species in the study stream suggests that technical bank habitat restoration measures are only of limited use for the restoration of highly specialised target species in conservation such as Barbus barbus and Chondrostoma nasus . However, introduction of particular artificial stream structures (in particular of artificial dead-wood fascines) was found to concentrate biomass and density of none-specialised fish species like Squalius cephalus , Alburnus alburnus , Gobio gobio or Rutilus rutilus . 相似文献
3.
M. C. Quist K. R. Pember C. S. Guy & J. L. Stephen 《Fisheries Management and Ecology》2004,11(2):107-116
Understanding spatial and temporal patterns in larval fish distributions is important for investigating factors related to recruitment variability and for developing sampling methodologies. Variation in species diversity (Shannon index) and density (number 100 m?3) of larval fishes from nearshore and pelagic habitats in Glen Elder Reservoir, KS, USA, was assessed during 1999 and 2000. Species diversity and densities of individual taxa were significantly higher (P < 0.05) in nearshore habitats than pelagic habitats during both years. Larval fish densities were generally higher in the year 1999 with higher spring water levels. Gizzard shad Dorosoma cepedianum (Lesueur) was the most abundant taxon in nearshore and pelagic habitats during both years. In addition, larval gizzard shad was sampled for the longest duration in the upper water column and overlapped with all taxa collected. High densities of gizzard shad in both habitats suggested that the potential for competitive interactions was high, especially given the lack of aquatic vegetation and habitat heterogeneity in littoral habitats. Most of the variation in larval fish diversity and density was because of temporal variation. If sampling effort must be limited and the purpose of sampling is to monitor larval diversity or density, attention should focus on sampling the same location over long time periods rather than across a variety of sampling locations. 相似文献
4.
D. F. Pires A. M. Pires M. J. Collares-Pereira M. F. Magalhães 《Ecology of Freshwater Fish》2010,19(1):74-86
Pires DF, Pires AM, Collares-Pereira MJ, Magalhães MF. Variation in fish assemblages across dry-season pools in a Mediterranean stream: effects of pool morphology, physicochemical factors and spatial context. Ecology of Freshwater Fish 2010: 19: 74–86. © 2009 John Wiley & Sons A/S
Abstract – Knowledge of patterns of refuge use by fish is critical for maintaining biodiversity in drought-prone streams. In this study, the fish assemblages of 21 dry-season pools in a Mediterranean stream were characterised and related to three sets of factors reflecting pool morphology, physicochemistry and spatial context. Fish were associated with the three sets of variables, with variation partitioning indicating that overall species richness and abundance were primarily related to pool morphology but relative species abundances were mainly associated with physicochemical contexts. In general, species richness was the highest but overall fish abundance was the lowest in large pools. Pools well shaded by riparian canopy held the highest richness and abundance of native fish, but relative species abundances and assembly structure varied among pools contingent on canopy cover, substrate composition and spatial location. These results suggested that conservation of fish diversity in Mediterranean streams requires networks of pools with diverse sizes and physicochemical contexts. 相似文献
Abstract – Knowledge of patterns of refuge use by fish is critical for maintaining biodiversity in drought-prone streams. In this study, the fish assemblages of 21 dry-season pools in a Mediterranean stream were characterised and related to three sets of factors reflecting pool morphology, physicochemistry and spatial context. Fish were associated with the three sets of variables, with variation partitioning indicating that overall species richness and abundance were primarily related to pool morphology but relative species abundances were mainly associated with physicochemical contexts. In general, species richness was the highest but overall fish abundance was the lowest in large pools. Pools well shaded by riparian canopy held the highest richness and abundance of native fish, but relative species abundances and assembly structure varied among pools contingent on canopy cover, substrate composition and spatial location. These results suggested that conservation of fish diversity in Mediterranean streams requires networks of pools with diverse sizes and physicochemical contexts. 相似文献
5.
东海中北部小眼绿鳍鱼食性的季节变化 总被引：2，自引：0，他引：2
根据2008年5月~2009年2月收集到的小眼绿鳍鱼胃含物样品,对其摄食习性的季节变化进行了研究。结果表明,小眼绿鳍鱼全年摄食的饵料种类数共有93种,磷虾类、长尾类和鱼类为其主要饵料类群。其食物组成存在季节差异,春季小眼绿鳍鱼以太平洋磷虾、脊腹褐虾和鳀鱼为主要食物;夏季以细巧仿对虾、脊腹褐虾、口虾姑和葛氏长臂虾为主要食物;秋季以太平洋磷虾、戴氏赤虾、细螯虾和鳀鱼为主要食物;冬季以鳀鱼、细螯虾、褐菖鲉和对虾为主要食物。摄食强度的季节变化呈显著差异(P0.05),春季最高,夏季最低;各个季节的主要饵料类群组成存在差异,但长尾类和鱼类在四个季节都有分布。通过与历史资料进行比较发现,东海小眼绿鳍鱼的食物组成与饵料生物的季节变化息息相关。 相似文献
6.
Generalist feeding strategies in Arctic freshwater fish: A mechanism for dealing with extreme environments 
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下载免费PDF全文 Sarah M. Laske Amanda E. Rosenberger Mark S. Wipfli Christian E. Zimmerman 《Ecology of Freshwater Fish》2018,27(3):767-784
Generalist feeding strategies are favoured in stressful or variable environments where flexibility in ecological traits is beneficial. Species that feed across multiple habitat types and trophic levels may impart stability on food webs through the use of readily available, alternative energy pools. In lakes, generalist fish species may take advantage of spatially and temporally variable prey by consuming both benthic and pelagic prey to meet their energy demands. Using stomach content and stable isotope analyses, we examined the feeding habits of fish species in Alaska's Arctic Coastal Plain (ACP) lakes to determine the prevalence of generalist feeding strategies as a mechanism for persistence in extreme environments (e.g. low productivity, extreme cold and short growing season). Generalist and flexible feeding strategies were evident in five common fish species. Fish fed on benthic and pelagic (or nektonic) prey and across trophic levels. Three species were clearly omnivorous, feeding on fish and their shared invertebrate prey. Dietary differences based on stomach content analysis often exceeded 70%, and overlap in dietary niches based on shared isotopic space varied from zero to 40%. Metrics of community‐wide trophic structure varied with the number and identity of species involved and on the dietary overlap and niche size of individual fishes. Accumulation of energy from shared carbon sources by Arctic fishes creates redundancy in food webs, increasing likely resistance to perturbations or stochastic events. Therefore, the generalist and omnivorous feeding strategies employed by ACP fish may maintain energy flow and food web stability in extreme environments. 相似文献
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Seasonal variation in habitat use by marsh fishes 总被引：1，自引：0，他引：1
Abstract— We used I-m2 throw traps to examine habitat use by smallsized fishes within a mosaic of wet prairies and sloughs in the headwaters of the St. Johns River, Florida between August 1992 and November 1995. Estimates of total fish density and biomass varied temporally, but did not differ significantly between habitats. Patterns of habitat use, however, differed among the five numerically dominant species. Bluefin killifish, mosquitofish, and golden topminnows were more abundant in sloughs than in wet prairies. In contrast, Everglades pygmy sunfish were more abundant in wet prairies than in sloughs. Finally, the abundance of least killifish did not differ between habitats. Fish densities were positively correlated with plant biomass (i. e., habitat complexity) and negatively correlated with water depth (i. e., hydrology). Species richness and composition were similar among habitats. However, consistent differences in the relative abundance of numerically dominant species between habitats indicated some degree of habitat-specific assemblage structure. Most species were concentrated into deeper sloughs during drying events. This assemblage of small-sized fishes appears to respond relatively rapidly to changes in habitat structure and hydrologic conditions. We therefore recommend that resource managers consider using fishes as indicator taxa to evaluate the efficacy of ongoing restoration and management efforts in wetland systems. 相似文献
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底栖硅藻能够较好地响应河流水环境变化,其群落物种组成与分布已被广泛应用于河流水质与生态状况的指示与评估。为了解流溪河底栖硅藻群落结构的时空异质性及其受河流水文与水质的影响,从上游到下游共设置了 20个样点,于2018年3月、6月、9月和12月进行季节采样和观测,采集底栖硅藻,同步测定了水体理化因子;在分析群落组成的基础上,进一步探究河流环境变量和空间变量对流溪河底栖硅藻群落的影响。结果表明,4次调查共检 出底栖硅藻276种,隶属于2纲、6目、9科、55属,底栖硅藻多样性具有明显的时空差异。在季节上,丰水期的物种丰 富度和真辛普森多样性指数高于枯水期。枯水期曲壳藻科的相对丰度超过50%,高于丰水期;而舟形藻科在丰水期 时相对丰度比枯水期高。在空间上,三级河流物种多样性最高,一级河流物种多样最低;一级河流和二级河流的优 势种主要以曲丝藻属的种类为主,三级河流的优势种主要以菱形藻属的种类为主。随着河流等级增加,曲壳藻科相 对丰度降低,而菱形藻科的相对丰度逐渐升高。冗余分析（RDA）表明,环境选择和空间要素对流溪河硅藻群落结构 均有显著影响,但营养盐水平比空间要素有更高的解释率。 相似文献
11.
Montaña CG, Winemiller KO. Local‐scale habitat influences morphological diversity of species assemblages of cichlid fishes in a tropical floodplain river.Ecology of Freshwater Fish 2010: 19: 216–227. © 2010 John Wiley & Sons A/S Abstract – We examined the taxonomic and morphological diversity of cichlid fish assemblages in a floodplain river in Venezuela during the dry season at two spatial scales: macrohabitats (lagoons, main channels and creeks) and mesohabitats (leaf litter, sand banks, rocky shoals and woody debris). Nonmetric multidimensional scaling did not reveal differences for species assemblages among macro and mesohabitats. The first two axes from canonical correspondence analysis based on 19 species and six physical variables modelled >61% of the taxonomic variation in assemblages from rock shoals and woody debris, and 55% of variation in assemblages from sand banks and leaf litter. Principal components analysis based on 22 morphological variables yielded two dominant axes that explained >86% of variation in the cichlid assemblages. Morphological diversity was analysed to test the idea that assemblage structure is nonrandom, with structurally complex habitats supporting more species with more functional morphological diversity than simple habitats. Average and standard deviation (SD) of the morphological Euclidean distances of local assemblages among mesohabitats tended to decrease or be constant as the number of species increased. Regressions of the average nearest neighbour distance (NND) and SD of NND with species richness resulted in low and negative slopes of species assemblages among mesohabitats. These relationships suggest that when more species are added to a habitat patch, assemblage morphospace remains approximately constant, species average similarity increases and species dispersion in morphological space becomes more uniform. Results support that cichlids partition habitat at the local scale but not at the macrohabitat scale. 相似文献
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David Kazyak Benjamin H. Letcher Joseph Zydlewski Matthew J. O'Donnell 《Ecology of Freshwater Fish》2014,23(4):516-526
Brook charr inhabit a wide variety of habitats and exhibit considerable growth variation within and among populations. We used biannual mark–recapture electrofishing surveys and PIT tags at two streams in coastal Maine to examine spatial and temporal variability in brook charr growth. We documented considerable stream‐to‐stream and year‐to‐year variation in the growth of coastal brook charr. Based on 2892 recaptures between 2006 and 2010, we developed a suite of linear mixed models to examine variation in individual growth rates at Stanley Brook as a function of environmental variables. We distilled physical habitat data from surveys in 2010 into principle components for entry into the growth model. Growth was related primarily to an interaction between season and body length, mean water temperature, and instream location. Growth rates were highest in the summer, and smaller individuals grew more rapidly than larger conspecifics in the same stream. Individuals using habitats closer to the head of tide grew faster than those in upstream locations. Physical habitat variation was not an important control of individual growth variation within Stanley Brook. We suggest local variability in growth rates should be considered when developing management strategies for coastal populations. 相似文献
13.
Influence of agriculture on in-stream habitat and fish community structure in Piedmont watersheds of the Chattahoochee River System 总被引：4，自引：0，他引：4
Abstract– Historical and contemporary fish collections were used to examine the influence of agricultural land use on fish communities in the central Chattahoochee River, USA. In-stream habitat data were also collected to examine the relationship between agricultural land use and stream habitat structure. We found a significant positive relationship between agricultural land use and in-stream sediment ( r 2 =0.43, P =0.01). Stream depth heterogeneity decreased significantly with increased sediment ( r 2 =0.39, P =0.02). Mainstream reaches draining agricultural lands had significantly lower levels of fish diversity than forested reaches ( r 2 =0.47, P < 0.01). Agriculture also explained significant variation in mainstream species abundances but was not a significant predictor of species diversity or species abundances in headwater reaches. Most pool species that use coarse substrates decreased in relative abundance with increasing agriculture in the watershed. Our results suggest that mainstream environments and their associated communities are more susceptible than headwater reaches to the effects of agriculture. This finding has important consequences for conservation, since mainstream reaches are reported to function as species refugia during pulse disturbance events (e. g., floods, droughts). 相似文献
14.
为了解长江口盐沼湿地优势鱼类群落结构及其种间关系,采用插网调查,利用2019年5—10月的调查数据,基于生态位宽度和生态位重叠度指数对长江口崇明东滩（31°27''N,121°56''E）和九段沙盐沼湿地（31°10''N,121°57''E）鱼类群落的优势种生态位进行研究。研究结果表明,春、夏、秋3个季节共采获10个优势种,其中鮻（Liza haematocheila）、花鲈（Lateolabrax maculatus）和拉氏狼牙虾虎鱼（Odontamblyopus rubicundus）在3个季节中均为优势种。在10个优势种中,时间生态位宽度值变化范围为0.11~1.70,其中拉氏狼牙虾虎鱼时间生态位宽度值最大,小黄鱼（Larimichthys polyactis）值最小;空间生态位宽度值变化范围为0.57~1.53,其中棱鮻（Liza carinatus）空间生态位宽度值最大,小黄鱼值最小。长江口盐沼湿地鱼类优势种生态位宽度呈现显著的季节性变化趋势。长江口盐沼湿地鱼类优势种的时空生态位重叠值较高,其中具重叠意义的鱼种对（species pairs）高达73.33%,具有显著重叠意义的鱼种对高达48.89%。结论认为,长江口盐沼湿地鱼类优势种的时空分布具有相似性,存在明显的竞争关系。 相似文献
15.
Abstract – Stream-fish assemblage and environmental data for 13 sites in the upper Brazos River, Texas, USA during 1997 and 1998 were used to assess the relationship between environmental conditions, and seasonal and spatial variation in fish species abundance and distribution patterns. There was considerable spatial variation in environmental conditions among sites. Spatial variation in species diversity and species composition was related to variation in conductance (salinity), depth and current velocity among sites and streams. Species diversity increased downstream and species composition shifted from primarily cyprinodontids upstream to cyprinids downstream. Among all dominant species, spatial components of variation in fish abundance were greater than seasonal components, suggesting that assemblage structure is determined more by average or persistent differences in environmental conditions among sites than by seasonal variation in environmental conditions. 相似文献
16.
Abstract Data from Lake Ontario tributaries were used to evaluate the efficacy of single-pass backpack electric fishing for stream fish monitoring by: testing the relationship between single-pass catch-per-unit-effort (CPUE) and multiple-pass-based population estimates; comparing species richness estimates derived from single-pass and multiple-pass data and assessing the concordance of fish assemblage patterns described using single-pass and multiple-pass data. Significant correlations were calculated between single-pass CPUE and removal-based population estimates for total catch, 15 species, six taxonomic families, five feeding and four reproductive guilds and tolerant/intolerant species. Strong correlations were more commonly associated with the abundance of individual species than other metrics. Capture probability was not affected by stream size or habitat complexity for most measures. Species accumulation curves and significant correlations ( r 2 = 0.9) between single-pass and multiple-pass electric fishing indicate that single-pass surveys provide a representative index of species diversity. In addition, within and among-site variation in fish community composition based on single-pass and multiple-pass data were similar. 相似文献
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Freshwater river mouths in large lakes are centres of biological activity, yet little is understood about the spatial and temporal dynamics of fish communities in these systems. In the Laurentian Great Lakes, we sampled littoral fishes over 3 years in six drowned (i.e., protected) river mouths to: (i) quantify spatial (among river mouths) and temporal (among years) variation, (ii) evaluate associations with environmental conditions and (iii) assess spatial patterns of community similarity. We sampled 6787 fish representing 43 species over the course of the study. Multivariate analyses indicated that variation in fish species composition was more strongly partitioned among river mouths than among years. Fish communities across the six river mouths were partitioned into three groups, a pattern we attribute to variability in anthropogenic disturbance and environmental conditions. Canonical correspondence analysis showed that fish species composition was associated with specific conductivity, vegetation cover, turbidity and pH, suggesting species–environment relationships are similar to those shown for Great Lakes coastal wetlands. Finally, we found a negative relationship between geographic distance and community similarity, suggesting that dispersal and/or environmental gradients play a role in shaping these river mouth fish assemblages. We conclude that Great Lakes drowned river mouths can harbour diverse and spatially variable fish assemblages that are driven by a combination of local and regional factors. 相似文献
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- To assess the impacts of human activity on fishes and fish habitat, impact assessment tools use single‐ and multi‐species approaches depending on the ecological and socio‐economic objectives. In Canadian aquatic ecosystems, single‐ and multi‐species impact assessments are guided by the Species at Risk Act and Fisheries Act, respectively. Yet, for species protected under the Species at Risk Act, the sparse data often require alternative approaches to risk assessment.
- The goal of this study was to evaluate whether a database‐derived multi‐species tool – the Habitat Ecosystem Assessment Tool (HEAT) – can be used for single‐species impact assessments. Using an empirical example of proposed drain maintenance in a tributary of Lake St. Clair, the net loss of suitable habitat was evaluated across six conservation targets, ranging from single species, such as the pugnose shiner (Notropis anogenus) and the yellow perch (Perca flavescens), to the entire fish assemblage. Model outcomes were compared across various habitat suitability indices, spatial resolutions, and environmental habitat layers.
- The net loss of suitable habitat varied widely across conservation targets and was greatest for the rare specialist species (pugnose shiner). Single‐species conservation targets were more sensitive to variation in spatial resolution and uncertainty in model input parameters. The results of this study emphasize that single‐ and multi‐species conservation targets should not be considered equal, especially when species differ in abundance and niche breadth.
- This study demonstrates the flexibility of HEAT for evaluating potential impacts of human disturbance on fishes and their habitat. Future development of this tool should expand beyond physical habitat, to include other factors relevant to species distribution and survival (e.g. biotic interactions).
20.
Abstract – Ecological models for stream fish range in scale from individual fish to entire populations. They have been used to assess habitat quality and to predict the demographic and genetic responses to management or disturbance. In this paper, we conduct the first comprehensive review and synthesis of the vast body of modelling literature on the brown trout, Salmo trutta L., with the aim of developing the framework for a demogenetic model, i.e., a model integrating both population dynamics and genetics. We use a bibliometric literature review to identify two main categories of models: population ecology (including population dynamics and population genetics) and population distribution (including habitat–hydraulic and spatial distribution). We assess how these models have previously been applied to stream fish, particularly brown trout, and how recent models have begun to integrate them to address two key management and conservation questions: (i) How can we predict fish population responses to management intervention? and (ii) How is the genetic structure of fish populations influenced by landscape characteristics? Because salmonid populations tend to show watershed scale variation in both demographic and genetic traits, we propose that models combining demographic, genetic and spatial data are promising tools for improving their management and conservation. We conclude with a framework for an individual‐based, spatially explicit demogenetic model that we will apply to stream‐dwelling brown trout populations in the near future. 相似文献