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Tatiane Mary Gogola Pitgoras Augusto Piana Pedro Rogrio Leandro da Silva Dhyego Amilton Topan Paulo Vanderlei Sanches 《Ecology of Freshwater Fish》2022,31(1):154-163
The reproductive activity of the fish assemblage in a large Neotropical reservoir was evaluated by surveying the occurrence of ichthyoplankton in response to spatial and temporal variation in environmental factors. Fish reproduction was investigated by capturing larvae along representative spatial gradients in the main body (longitudinal) and arms (lateral) of the reservoir. After identification, the captured larvae were classified into different groups according to the functional traits of their parental stock. Sampling occurred monthly at night from October to March over five reproductive periods between 2009 and 2016, using conical-cylindrical plankton nets with flowmeter. Water samples were taken simultaneously allowing the measurement of environmental factors related to reproductive activity. The relationship between the environmental factors and the functional traits was assessed using RLQ and fourth-corner analyses. An evaluation of 51,995 larvae revealed there was greater larval abundance in the lacustrine and transition zones of both longitudinal and lateral gradients. Occurrences often correlated with temporal instead of spatial gradients. Higher rainfall correlated with abundances of detritivorous and migratory species. Higher water levels correlated with higher abundances of non-native species, species without parental care, with external fecundation, and partial spawning. Dry periods, with lower water and higher dissolved oxygen, correlated with higher abundances of insectivores and sedentary species. Although the presence of a dam-free stretch of river upstream of the reservoir had a positive influence on fish larvae in the fluvial zone, the results did not show differentiation along either gradient. Thus, the composition of the functional groups of fish species that reproduce in the Itaipu Reservoir appears to be predominantly influenced by the temporal variation in environmental factors rather than the formation of spatial gradients. 相似文献
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C. N. Gibbins C. Soulsby M. J. Jeffries & R. Acornley 《Fisheries Management and Ecology》2001,8(6):463-485
Kielder Reservoir and the Kielder water transfer scheme have been operational since the early 1980s. The hydro-ecological changes that occur in the River North Tyne and the River Wear as a result of Kielder operations are highlighted and release policy changes designed to minimize impacts on salmonid fish are described. The Kielder Reservoir release regime results in sudden and marked changes in flow in the North Tyne. These changes affect the availability of suitable habitat for newly emerged 0+ Atlantic salmon Salmo salar L. and potentially lead to the drying out of areas used for spawning. Physical Habitat Simulation (PHABSIM) models suggest that the reservoir compensation flow provides adequate habitat for older 0+ fish but limits the availability of spawning habitat. A seasonally variable compensation and hydroelectric power (HEP) release regime that limits impacts and increases suitable spawning and 0+ habitat is described. Transfers of water to the River Wear result in short-term changes in the abundance of certain invertebrate species, although there is no evidence that the river's invertebrate fauna has been permanently altered. Consequently, it is unlikely that fish are affected indirectly by transfers through reductions in the abundance of their invertebrate prey. Transfers allow abstractions for potable and industrial water supply to continue without breaching the river's statutory Minimum Maintained Flow (MMF). The PHABSIM models suggest that this augmentation helps avoid the loss of salmonid habitat during summer dry periods. Simulation of the impacts of some alternative regimes indicates that salmonid habitat could be increased further but at the expense of natural flow and habitat variation. Research findings do not suggest the need for changes to the transfer release regime. 相似文献
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We hypothesised and tested a hierarchical organisation model where riparian landcover would influence bank composition and light availability, which in turn would influence instream environments and control fish assemblages. The study was conducted during the dry season in 11 headwater tributaries of the Sorocaba River in the upper Paraná River Basin, south‐eastern Brazil. We focused on seven environmental factors each represented by one or multiple environmental variables and seven fish functional traits each represented by two or more classes. Multivariate direct gradient analyses suggested that riparian zone landcover can be considered a higher level causal factor in a network of relations that control instream characteristics and fish assemblages. Our results provide a framework for a hierarchical conceptual model that identifies singular and collective influences of variables from different scales on each other and ultimately on different aspects related to stream fish functional composition. This conceptual model is focused on the relationships between riparian landcover and instream variables as causal factors on the organisation of stream fish assemblages. Our results can also be viewed as a model for headwater stream management in that landcover can be manipulated to influence factors such as bank composition, substrates and water quality, whereas fish assemblage composition can be used as indicators to monitor the success of such efforts. 相似文献
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Tatiane M. Gogola Paulo V. Sanches Éder A. Gubiani Pedro R. L. da Silva 《Ecology of Freshwater Fish》2013,22(1):95-105
For understanding the reproductive dynamics of fish assemblages and their relationship with environmental conditions, we need to know more about spawning areas and periods. Studies on temporal and spatial patterns of occurrence of fish eggs and larvae are important for obtaining this kind of information quickly and accurately. In this study, we analysed spatial and temporal patterns of fish larvae in different biotopes in a stretch of the floodplain of Upper Parana River, in Ilha Grande National Park, southern Brazil. We carried out night sampling during six spawning periods, from 2001 to 2008. We selected 18 sampling sites distributed in the mainstream, tributaries and lagoons, encompassing several types of biotopes. We observed significant spatial and temporal differences among biotopes in the composition and structure of the fish larvae assemblages. Lentic environments favoured the development of sedentary and migratory species, whereas tributaries were used as migratory routes and spawning areas. The assemblage in period I differed from the assemblages of other periods, probably because of the presence of dams in the Parana River. No association was observed between environmental variables and spatial and temporal patterns of the ichthyoplankton assemblages. Hence, conservation measures are essential to maintain the environmental integrity of spawning (tributaries) and development areas (lagoons) for the maintenance of biodiversity in the floodplain of Upper Paraná River. 相似文献
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长江口青草沙水库正式供水前的鱼类群落结构特征 总被引：7，自引：0，他引：7
为研究上海青草沙水库的鱼类物种组成、多样性及其空间变化,2010年7--10月在该水库共捕获鱼类993尾,隶属5目,18种,其中淡水鲤形目鱼类最多,占总物种数的72.2％.群落优势种为贝氏(鳖)、刀鲚、鲫、光泽黄颡鱼.聚类分析表明,鱼类群落类型存在较显著的空间差异,刺网网目大小对渔获物物种组成有较显著的影响.物种多样性与丰富度和均匀度均显著正相关,但更多地受丰富度的影响.单因素方差分析表明,鱼类物种多样性在空间上无显著差异.4种摄食功能群中,无脊椎动物食性(44.4％)和杂食性(33.3％)鱼类物种数比例较高;4种生态类群中,定居性鱼类占绝对优势(77.8％).青草沙水库鱼类群落表现出淡水或长江口低盐淡水区鱼类区系的主要特征,与以近海鲈形目鱼类为优势的长江口邻近水域的鱼类群落差异巨大,推测水库建设导致的隔离与盐度下降是形成该水库鱼类群落趋于淡水区系的主要原因. 相似文献
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Jennifer L Kelley Pauline F Grierson Shaun P Collin Peter M Davies 《Fish and Fisheries》2018,19(4):716-728
Aquatic ecosystems are facing escalating threats from urbanization, habitat loss and projected impacts of climate change, which both individually and in combination have the potential to fundamentally alter ecosystem functioning. While it is well established that habitat disturbances can affect the composition and diversity of aquatic communities, only recently have studies considered whether such impacts result in changes in species’ functional traits. We consider how functional traits of freshwater and marine fishes respond to environmental change, and how shifts in the expression of these traits can impact community dynamics and key ecological processes, including trophic interactions and nutrient transfer. We find that a multitude of functional traits, including behavioural and sensory traits, is sensitive to habitat disturbances. We demonstrate how these trait changes can be used to reveal hidden “ecological diversity” as well as serving as early indicators of environmental perturbation. We conclude that management strategies that consider the fundamental biological responses of fishes to habitat disturbance will be particularly effective in determining causal relationships within the ecological network. While detailed information on trait function is often lacking, even some general understanding of trait function and importance will facilitate targeted and efficient ecosystem management. We urge fisheries biologists and aquatic ecosystem managers to consider the role of functional traits in facilitating effective habitat restoration and management. 相似文献
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渤海鱼类群落功能群及其主要种类 总被引：9，自引：3，他引：6
根据2009年8月和10月对渤海渔业资源的底拖网调查,采用胃含物分析、聚类分析和功能群划分的方法研究了渤海鱼类群落的功能群组成及其主要种类。结果表明,渤海夏、秋季鱼类群落包括7个功能群,分别为浮游动物食性功能群、杂食性功能群、底栖动物食性功能群、虾食性功能群、虾/鱼食性功能群、鱼食性功能群和广食性功能群;其中主要功能群为浮游动物食性功能群、杂食性功能群和虾/鱼食性功能群;主要种类有小黄鱼、蓝点马鲛、斑、赤鼻棱鳀、银鲳和黄鲫。圆筛藻、中华哲水蚤、太平洋磷虾、长额刺糠虾、中国毛虾、甲壳类幼体、日本鼓虾、六丝矛尾虎鱼、小黄鱼、双壳类和腹足类是当前渤海夏、秋季鱼类群落的主要饵料种类。 相似文献
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Studies on fish eggs and larvae are important for understanding the recruitment dynamics of fish assemblages and their relationships with environmental conditions. Located in the upper reaches of the Yangtze River, China, the Three Gorges Reservoir (TGR) is one of the largest reservoirs in the world, where the fish resource ecology has drawn great attention. With the purpose of evaluating fish recruitment in the TGR, in the present study, samples of fish eggs and larvae were collected at Luoqi County, the upper end of the TGR, from April 15th to July 29th 2011. From the samples collected, we identified 46 fish species belonging to nine families and five orders. The most abundant species were in the Cultrinae, Gobiidae, and Gobioninae. An estimated 12.4 billion fish eggs and larvae drifted into the TGR. There were approximately 2.6 billion Pseudolaubuca sinensis, 1.9 billion Hemiculter leucisculus, and 1.8 billion Gobiidae. The spawning grounds of fishes that release pelagic eggs are in the reaches 13–162 km upstream from our sampling site. More attention should be paid to protecting the habitat in large free stretches upstream of the reservoir, since these areas are important spawning grounds for many fishes. Also, an ample natural flooding regime should be retained in this region. 相似文献
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Jose Luis Poveda-Cuellar Edwin Orlando Lpez Delgado Pamela Tatiana Zúiga-Upegui Francisco Antonio Villa Navarro 《Ecology of Freshwater Fish》2022,31(1):87-101
Understanding the mechanisms that structure communities have been a major challenge in ecological theory. Functional trait-based approaches are increasingly used for studying the processes underlying community assembly. However, species-poor systems of Andean streams these processes are largely unknown. Tropical Andean streams are highly variable in space-time and characterised by the harsh or stable environment, resulting in a high taxonomic and ecological diversity. In this study, we tested the influence of environmental variables on the fish functional structure. We proposed that in ecosystems with harsh environments, environmental filtering will structure fish assemblages, and in ecosystems with a more stable environment, limiting similarity will prevail, increasing functional diversity. We analysed fish assemblages using functional diversity indices, fourth-corner RLQ analyses and multiple regression models. Environmental variables such as altitude, stream width, sub-Andean vegetation and pH influenced functional diversity. For instance, high values of functional redundancy were registered at high elevation streams, reflecting fish assemblages composed of highly dominant species with similar functional traits such as species of the genus Astroblepus. However, we found differences between Astroblepus species in the number and distance of gill rakers which might indicate resource partitioning and coexistence. On the other hand, our results show both stochastic dynamics and environmental filtering are structuring fish assemblages in low and high elevation Andean streams respectively. 相似文献
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大型水库实施生态调度是修复河流水文情势、维持河流生态系统健康的重要手段。江垭水库位于溇水干流下游的张家界慈利县，是澧水流域具有重要防洪意义的大型水库。本研究通过环境DNA采样、IHA水文指标变动分析和文献资料总结等方法，开展了江垭坝下水文情势及鱼类繁殖需求的关系研究，提出了江垭水库生态调度需求及建议。2021年9月在溇水干支流综合调查到鱼类55种，与上世纪90年代相比，流水性种类在干流江段显著减少了51.35%；按照生态调度优先等级评估原则，确定江垭水库生态调度的主要目标物种为产漂流性卵的银鲴、银鮈、贝氏?和产粘沉性卵的鲤、鲫；江垭建坝前后下游水文情势变化较大，发生高度改变且对鱼类洄游产卵及鱼卵发育有重要作用的水文指标包括：年最大1日、3日平均流量指标，年出现高流量脉冲事件的次数和持续时间，以及连续日流量上涨率。以促进坝下不同产卵类型的鱼类繁殖为目标，江垭水库生态调度一方面需要恢复一定的高流量脉冲次数和历时，另一方面需要控制下游的水位日降幅，通过泄放合理的生态流量来维持下游鱼类的生物多样性。 相似文献
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为探讨金沙江下游溪洛渡和向家坝水电站蓄水运行对下游江段鱼类早期资源群聚动态的影响,基于2016-2020年宜宾江段鱼类早期资源调查数据,探究其资源种群结构与年际变化趋势。使用半圆弶网采集漂流性卵,通过分子生物学方法进行种类鉴定,并计算鱼卵丰度。结果表明,宜宾江段共计采集鱼卵20种,主要优势种为吻鮈(Rhinogobio typus)和寡鳞飘鱼(Pseudolaubuca engraulis);估算出鱼卵年均径流量为15.07×106粒,其中漂流性卵为9.89×106粒,年际间总体呈增加趋势;推算采样点以上分布有产漂流性卵鱼类产卵场3处;从多样性指数和相似度指数看,宜宾江段鱼卵种类组成结构较为稳定,年际间变化不大。尽管受金沙江下游水电工程开发的影响,宜宾江段作为长江上游珍稀特有鱼类国家级自然保护区的重要组成部分,仍是产漂流性卵鱼类产卵繁殖的重要分布区,但以小型鱼类为主,圆口铜鱼(Coreius guichenoti)、长鳍吻鮈(Rhinogobio ventralis)等长距离洄游性鱼类鱼卵没有监测到。建议继续加强圆口铜鱼、长鳍吻鮈等鱼类的增殖放流;针对产漂流性卵小型鱼类的生态需求,开展... 相似文献
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Environmental and spatial processes: what controls the functional structure of fish assemblages in tropical rivers and headwater streams? 
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下载免费PDF全文 In this study, we investigated functional structure patterns of tropical headwater and river fish assemblages. We hypothesised that environmental conditions are primarily structuring headwater streams leading to functionally clustered assemblages, whereas processes that favour functional overdispersion would guide river assemblages. For 27 headwater streams and 22 rivers, we used eight functional traits for calculating two functional indexes: mean pairwise distance (MPD) and net relatedness index (NRI). We performed linear regressions between indexes and species richness, a multiple regression between NRI and eight environmental variables and a variation partitioning to disentangle the role of environment and space on NRI. Our findings indicate that fish assemblages of headwaters are structured by environmental conditions as most assemblages in this habitat displayed a tendency to clustering and MPD/NRI were not correlated with species diversity, whereas the opposite pattern was observed for river habitat. Four environmental variables (channel depth, water velocity, dissolved oxygen and turbidity) explain 56% of functional structure variation. These variables seem to function as selective filters in headwaters, whereas channel depth may be determinant for functional overdispersion of river fish assemblages. Components associated with space are also influencing the functional structure. Limitations of species dispersal through space (between both habitat types) appear as a possible cause to this. In this sense, both environmental conditions and processes linked with space are capable of influencing the functional structure of tropical headwater streams and river fish assemblages. 相似文献
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基于红水河流域开发特点和鱼类群聚组成特征，构建红水河鱼类生物完整性评价指标体系，评价梯级开发对红水河不同生境类型的鱼类生物完整性的影响。河流参照状态和基准值由1982—1994年鱼类历史监测数据分析得到；监测值是2013年调查的鱼类数据；现状值为2018年鱼类数据。针对红水河鱼类区系特点和高强度水电开发特征，选取总种类数占期望值比例、鲤科鱼类所占比例、鲿科鱼类所占比例、鲇科鱼类所占比例、耐受性鱼类个体所占比例、渔获物中出现的科数所占比例、杂食性鱼类个体所占比例、底栖动物食性鱼类个体所占比例、顶级肉食性鱼类所占比例和外来种个体所占比例等10个指标构建红水河IBI指标体系。结果表明：2013年25个采样江段的IBI值为38 ~ 80分，均值62分。其中，24%的江段生物完整性等级为“好”；32%的江段生物完整性等级为“一般”；44%的江段生物完整性等级为“差”。从生境类型来看，支流生物完整性明显优于水库、库尾回水区。此外，现状数据评价的结果为：2018年红水河IBI值为64分，高于2013年均值62分，生物完整性均处于“一般”等级。 相似文献
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东海生态系统中鱼卵、仔稚鱼种类组成、数量分布及其与环境因素的关系 总被引：5，自引：3，他引：2
为了解当前东海生态系统中鱼卵、仔稚鱼种类组成和数量分布的现状及其变化与物理环境因素的关系,根据2006年11月—2008年6月5个航次的鱼卵、仔稚鱼和物理环境调查资料,对鱼卵、仔稚鱼种类组成、数量分布与产卵场物理环境进行分析,探讨不同季节、不同年份鱼卵、仔稚鱼种类组成和数量分布的变化及其与物理环境的关系。结果显示,5个航次采集到74 813粒鱼卵、16 826尾仔稚鱼,共有135个种类。其中,鉴定到种的有109种,隶属于15目67科99属,还有17个种类仅能鉴定到属、6个种类仅能鉴定到科和3个种类仅能鉴定到目。2006年—2007年秋季、冬季和春季鱼卵、仔稚鱼的种类和数量随着季节变化逐渐增多;2008年春季的种类和数量较2007年春季明显偏少;2008年初夏种类的数量与2008年春季基本相近,但鱼卵的数量明显增多,仔稚鱼的数量基本相近。42种优势种类、重要种类和主要种类构成当前东海生态系统中鱼卵、仔稚鱼种类组成的主要成分。东海表层水温和盐度分布有显著的季节变化。秋、冬季表层水温锋面强度最强,春季次之,初夏最弱;锋面的位置秋季离岸最近,冬季次之,春季和初夏离岸最远,冬季偏南,初夏季节北移。表层盐度锋面主要分布在近岸区域,与岸线大致平行,其强度冬季最强,春、秋季次之,初夏季节最弱。秋、冬季节陆架深水海域的水温较沿岸海域高,鱼类生殖群体在陆架深水高温区产卵;春季和初夏季节沿岸海域明显升温,鱼类生殖群体由深水区向近岸海域进行生殖洄游,产卵场分布由陆架中部向近岸海域扩展,并在近岸海域形成了中心产卵场。鱼卵和仔稚鱼的分布与温、盐锋面和种类的温、盐属性的关系密切,主要分布在温度锋面暖水一侧,并有各自最适宜的温度和盐度范围。水温、盐度与种类的繁殖生物学特性是导致鱼卵和仔稚鱼种类组成与数量发生变化的主要因素;适宜的温度和盐度范围、锋区的辐聚和卷夹作用以及种类的生物学属性是影响鱼卵和仔稚鱼数量分布以及密集分布区形成的主要因素。 相似文献
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为了解西部内陆水库放牧式养殖西伯利亚鲟的生产潜力,以甘肃省酒泉市的红砂墩水库为例,调查了水库中底栖动物的资源以及西伯利亚鲟的食物组成和季度摄食量。结果显示:水库中底栖动物12种,其中,腹足类3种,寡毛类3种,水生昆虫3种,甲壳类2种。2龄西伯利亚鲟的食物组成包括调查所得的全部底栖生物,以甲壳类、腹足类、寡毛类和昆虫幼虫为主要食物,随着鲟鱼的生长,秋冬季后开始逐渐摄食小型底栖鱼类。研究表明2龄西伯利亚鲟食谱范围较广,适合在此类水库中养殖。另对底栖动物的鱼产潜力进行估算,该水库底栖动物每年提供给鲟鱼生长的鱼产潜力为18.55 t。 相似文献
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Luciana L. Santos Naraiana L. Benone Bruno E. Soares Ronaldo B. Barthem Luciano F. A. Montag 《Ecology of Freshwater Fish》2019,28(3):424-433
Studies of trait–environment relationships provide important tools for the prediction of the response of biological communities to environmental alterations. The Amazon basin presents enormous potential for the development of research on this type of relationship, given the diversity of both its fish fauna and the aquatic ecosystems this fauna inhabits. The present study investigated the association between local environmental variables and the functional traits of fish in 54 streams of six major Amazonian basins. We identified the relationship between the characteristics of the streams (channel morphology, channel habitat units, riparian vegetation cover, large woody fragments and instream cover for aquatic organisms) and fish traits related to locomotion, habitat use and feeding behaviour. The fish fauna of the broader, deeper and more slowly flowing streams was dominated by nektobenthic species that exploit autochthonous resources such as fish and invertebrates. In narrow, fast‐flowing streams, by contrast, there was a predominance of benthic fishes with varying feeding habits, including periphytivorous and invertivorous species. Narrow, shady streams were inhabited by nektonic species adapted for the exploitation of resources from the marginal vegetation. The results of this study contribute to the understanding of the association between the functional structure of fish assemblages and local environmental variables in Amazonian streams. We hope that these findings will stimulate further research into the natural variation in stream fish assemblages that will ensure the development of more effective management strategies that better protect these important aquatic ecosystems. 相似文献