Articles de revues : « Macroinvertebrate community assemblages »

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Jyväsjärvi, Jussi, Marko Järvinen et Heikki Hämäläinen. « Spatial community concordance of summer phytoplankton and profundal macroinvertebrates in boreal lakes ». Canadian Journal of Fisheries and Aquatic Sciences 71, n^o 12 (décembre 2014) : 1776–83. http://dx.doi.org/10.1139/cjfas-2014-0135.

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Reliance of profundal benthic macroinvertebrate assemblages on epilimnetic algal production — a key element of pelagic–benthic coupling — is a well-recognized phenomenon in the literature but the details are still poorly understood. In particular, the importance of taxonomic composition of algal communities and associated qualitative aspects of the settling material to benthic invertebrates is poorly known. We addressed this issue by investigating concordance of summer phytoplankton and profundal macroinvertebrate community composition using data from 47 boreal lakes. We examined community variation and environmental correlates of phytoplankton and macroinvertebrates with nonmetric multidimensional scaling ordinations. We also used cluster analysis to group sites according to their macroinvertebrate assemblages and evaluated the differences in phytoplankton composition and class-specific relative abundance among the clusters. Community concordance was evaluated with Procrustes rotation and partial Mantel tests, using oxygen concentration and phytoplankton biomass — the main drivers of macroinvertebrate community structure — as controlling factors. Procrustes and Mantel tests suggested congruence between macroinvertebrate and summer phytoplankton community composition. The concordance remained significant even after controlling for oxygen and biomass, by partial Mantel tests, suggesting a unique effect of phytoplankton species composition on macroinvertebrate assemblages. The four groups of lakes clustered by their macroinvertebrate assemblages also differed significantly in their phytoplankton taxa composition, and there were among-cluster differences in relative abundance of the seven most abundant phytoplankton classes. Our findings of community concordance of phytoplankton and profundal macroinvertebrates suggest a functional dependency of these two components, but further studies are needed to verify the actual causal mechanisms.

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Yan, Shengjun, Tao Sun, Xuan Wang, Dan Liu, Yunlong Zhang et Zhifeng Yang. « Responses of Macroinvertebrate Community Temporal Dissimilarity and Abundance to the Water Level Fluctuation Range in a Shallow Lake ». Water 13, n^o 23 (1 décembre 2021) : 3380. http://dx.doi.org/10.3390/w13233380.

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Variations in the hydrological regime are among the anthropogenic pressures affecting biological assemblage structure in shallow freshwater lakes. We estimated the effects of the water level fluctuation range on the temporal dissimilarity of the macroinvertebrate community by sampling benthic macroinvertebrate assemblages monthly in 2017 and bimonthly in 2018. Then, we applied a boosted regression trees (BRT) model to quantitatively analyzing the relationship between macroinvertebrate abundance and microhabitat factors in different seasons. To distinguish differences in water level fluctuations at the sample site scale, we proposed a variable, namely, the percentage of water level fluctuation range (PWLFR). The results were as follows. (1) An increased water level fluctuation range would lead to more temporally heterogeneous macroinvertebrate communities. Temporal dissimilarity of macroinvertebrates increased linearly in response to increasing water level fluctuation range. (2) Species abundance presented seasonal characteristics, and the dominant factors affecting species abundance varied with the seasons. PWLFR was the dominant variable explaining macroinvertebrate abundance in summer. Macroinvertebrate abundance showed positive effects with increasing PWLFR. (3) The interaction between chlorophyll a and PWLFR in summer promoted an increase in macroinvertebrate abundance. These findings may provide a basis for the formulation of effective ecological water replenishment management decisions aimed at maintaining the stability of shallow lake ecosystems in arid and semi-arid regions.

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Gething, Kieran J., Matthew C. Ripley, Kate L. Mathers, Richard P. Chadd et Paul J. Wood. « The influence of substrate type on macroinvertebrate assemblages within agricultural drainage ditches ». Hydrobiologia 847, n^o 20 (6 octobre 2020) : 4273–84. http://dx.doi.org/10.1007/s10750-020-04416-6.

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Abstract Artificial drainage ditches are common features in lowland agricultural catchments that support a wide range of ecosystem services at the landscape scale. Current paradigms in river management suggest activities that increase habitat heterogeneity and complexity resulting in more diverse floral and faunal assemblages; however, it is not known if the same principles apply to artificial drainage ditch systems. We examined the effects of four artificial substrates, representing increasing habitat complexity and heterogeneity (bricks, gravel, netting and vegetation), on macroinvertebrate community structure within artificial drainage ditches. Each substrate type supported a distinct macroinvertebrate community highlighting the importance of habitat heterogeneity in maintaining macroinvertebrate assemblages. Each substrate type also displayed differing degrees of community heterogeneity, with gravel communities being most variable and artificial vegetation being the least. In addition, several macroinvertebrate diversity metrics increased along the gradient of artificial substrate complexity, although these differences were not statistically significant. We conclude that habitat management practices that increase habitat complexity are likely to enhance macroinvertebrate community heterogeneity within artificial drainage channels regardless of previous management activities.

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Arce, Juan A., Fernando Alonso, Antonio Camacho et Eugenio Rico. « Do native white-clawed crayfish impact macroinvertebrate assemblages in Mediterranean limestone headwaters ? » Knowledge & ; Management of Aquatic Ecosystems, n^o 420 (2019) : 33. http://dx.doi.org/10.1051/kmae/2019024.

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Crayfish are among the largest aquatic macroinvertebrates in rivers and streams. Their trophic ecology is important for the understanding of the functioning of benthic communities. This is relevant in key areas, such as headwaters, as they partly condition the processes occurring downstream. To shed light on the effects of native white-clawed crayfish, Austropotamobius pallipes, on local macroinvertebrate assemblages from running headwaters, a three-month mesocosm-based field study was designed. Collection and subsequent analysis of benthic samples under different crayfish density levels yielded a set of metrics indicative of short-term impacts at general and taxonomic scales. Neither significant positive nor negative effects on the community were evident in terms of richness, diversity, dominance and biomass. A combination of highly patched distributions of macroinvertebrates along with a weak impact of crayfish foraging activity is considered to explain this lack of effects. Only temporal changes associated with particular biological cycles appeared for some of the main taxa. Based on the results, we are not able to determine whether the white-clawed crayfish perceptibly disturbs the structure and composition of the local macroinvertebrate assemblages in the short-term. Thus, its use in future restocking projects is supported.

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Minshall, G. Wayne, Todd V. Royer et Christopher T. Robinson. « Response of the Cache Creek macroinvertebrates during the first 10 years following disturbance by the 1988 Yellowstone wildfires ». Canadian Journal of Fisheries and Aquatic Sciences 58, n^o 6 (1 juin 2001) : 1077–88. http://dx.doi.org/10.1139/f01-056.

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We evaluated the effects of disturbance on stream benthic macroinvertebrates at the ecological scales of time, stream size, and burn extent in six segments of Cache Creek over the first 10 postfire years. Postfire changes in macroinvertebrate taxa richness, density, and dominant taxa in the burn streams were significantly different from those in the reference stream. Chironomidae and Baetis typically comprised 4060% of the macroinvertebrate assemblages of burned streams but only 1518% of the assemblage in the reference site. Coefficients of variation for the 10-year period indicated that richness, density, biomass, and Baetis abundance were more variable (1.23.5 times higher) in the burn streams than in the reference stream and that variability in Chironomidae abundance in burn sites increased with stream size. Fire effects were not attenuated progressively with increasing stream size, probably because the proportion of the catchment burned did not decrease. However, similar-sized streams in which 6871% of their catchments burned were more severely disturbed than those in which only 3947% burned. Long-term effects on the macroinvertebrate community were due largely to the loss of terrestrial vegetation and increased runoff, which caused severe alterations in stream channel conditions and large-scale bedload movement.

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Beasley, G., et P. E. Kneale. « Investigating the influence of heavy metals on macro-invertebrate assemblages using Partial Cononical Correspondence Analysis (pCCA) ». Hydrology and Earth System Sciences 7, n^o 2 (30 avril 2003) : 221–33. http://dx.doi.org/10.5194/hess-7-221-2003.

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Abstract. This paper defines the spectrum of impairment to stream macroinvertebrates arising from urban runoff. Field sampling of stream sediments at 62 sites across Yorkshire, UK was used to investigate the influence of heavy metals and habitat on macroinvertebrate family distribution using partial Canonical Correspondence Analysis (pCCA). Increasing urbanization and trafficking was associated with increasing levels of metal pollution but, even when traffic is light, family numbers can be reduced by 50%. Industrial areas and motorway runoff depress macroinvertebrate numbers but drainage from streets with no off-road parking in residential areas can have similar impacts. The heavy metals in the sediment accounted for approximately 24% of the variation in macroinvertebrate community composition while the physical habitat variables used in RIVPACS (River InVertebrate Prediction And Classification System) (Wright, 2000) accounted for an additional 30%. Zinc and nickel were the main metal influences regardless of the time of sampling; at these sites copper is less than critical. Results agree with those reported in other studies in which families mainly from the orders Ephemeroptera (mayfly), Plecoptera (stonefly) and Tricoptera (caddisfly) displayed metal sensitivity in that they were absent from metal polluted streams. However, within each of these orders, a continuum of sensitivity is evident: this highlights the risks of generalising on orders rather than using family or indeed species data. Keywords: macroinvertebrates, heavy metals, urban streams, tolerance, sensitivity

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Clements, Williams H., Donald S. Cherry et John Cairns Jr. « Impact of Heavy Metals on Insect Communities in Streams : A Comparison of Observational and Experimental Results ». Canadian Journal of Fisheries and Aquatic Sciences 45, n^o 11 (1 novembre 1988) : 2017–25. http://dx.doi.org/10.1139/f88-235.

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This research compares effects of heavy metals on macroinvertebrate communities in outdoor experimental streams with those observed at impacted field sites. Natural assemblages of aquatic macroinvertebrates were established on substrate-filled trays which were then transferred to outdoor stream mesocosms. Exposure of these communities to low levels of copper and zinc (target concentration = 12 μg/L) significantly reduced the number of taxa, number of individuals, and abundance of most dominant taxa within 4 d. After 10 d, control streams were dominated by Ephemeroptera and Tanytarsini chironomids, whereas treated streams were dominated by Hydropsychidae and Orthocladiini. Responses of benthic communities to metals observed at the Clinch River (Russell Co., Virginia), a system impacted by copper and zinc, were similar to those in experimental streams. Ephemeroptera and Tanytarsini, which comprised 38–46% of the macroinvertebrate community at upstream reference stations, were significantly reduced at all effluent sites. As in treated experimental streams, impacted stations were dominated by Hydropsychidae and Orthocladiini. The similarity of our experimental results to those obtained from Clinch River field sites suggests that outdoor stream mesocosms may be employed to predict macroinvertebrate community responses to heavy metals.

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Drost, Annemieke M., Andre R. Siebers, Amael Paillex, Benjamin Misteli, Edwin T. H. M. Peeters et Christopher T. Robinson. « Long-lasting effects of experimental flow intermittency on alpine stream macroinvertebrates (Val Roseg, Switzerland) ». Hydrobiologia 849, n^o 8 (29 mars 2022) : 1931–46. http://dx.doi.org/10.1007/s10750-022-04843-7.

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AbstractChanging weather patterns and receding glaciers are predicted to increase flow intermittency in alpine streams. If aquatic macroinvertebrate communities largely comprise taxa adapted to perennial flows, an increase in flow intermittency substantially reduces biodiversity and affects functional processes. We conducted a before-after-control-impact field experiment to examine how macroinvertebrate communities in an alpine headwater stream responded to and recovered from a repeated experimental increase in flow intermittency. Flow in one channel was manipulated to simulate increased summer intermittency (June–September) over two consecutive years, whilst an adjacent channel served as a control. We monitored the density of benthic macroinvertebrates, periphyton and organic matter at approximately monthly intervals over three years during the snow-free period. Before manipulation, both channels had similar ecological properties. The flow manipulation reduced the overall macroinvertebrate density, and especially the proportional rheophile density, across both years. Recovery of the macroinvertebrate community following experimental flow intermittency took more than a year, and longer than our study period. This could be due to long aquatic life stages, dispersal limitation and biotic interactions. We conclude that climate-induced changes in alpine stream flow regimes can lead to a fundamental shift in macroinvertebrate assemblages through local extinctions, mostly of rheophilic species.

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Jiang, Wanxiang, Baozhu Pan, Jing Chen, Xiaoming Jiang, Henglun Shen et Tianshun Zhu. « Macroinvertebrate Communities in a Lake of an Inter-Basin Water Transfer Project and Its Implications for Sustainable Management ». Water 12, n^o 7 (3 juillet 2020) : 1900. http://dx.doi.org/10.3390/w12071900.

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In the present study, we choose the Weishan Lake, one of important water transfer and storage lakes on the eastern route of the South-to-North Water Diversion Project (SNWD) in China, to clarify how the community structure and assemblage-environment relationships of macroinvertebrates varied across three typical habitats (the River Mouth, Canal and Lake regions) over the four seasons in 2012. A total of 72 taxa belonging to 3 phyla, 9 classes and 24 families were recorded, with tolerant oligochaetes and chironomids as the dominant taxa. The environmental conditions and macroinvertebrate assemblages were clearly separated at spatial and temporal scales. Assemblage structure showed both significant but larger spatial than seasonal variations, with a clear separation of sites from three regions in an ordination plot. Compared to the temporal scale, more indicator species were retained to be responsible for the regional differences according to the two-way cluster analysis. Different environmental variables were significant for distinguishing macroinvertebrate assemblages among four seasons, and among them, pH was the only variable which was retained in all models. Our study provided useful background information of environmental characteristics and macroinvertebrate communities in a typical water transfer and storage lake before the water transfer of the SNWD. After the operation of SNWD, we envisage inter-basin water transfer (IBWT), which is usually accompanied by water level rise, nutrient pattern change and biota succession, will seriously affect recipient basins. Therefore, we propose several management strategies for SNWD: (1) target and detailed data should be collected on a timely basis; (2) government should prevent water pollution and adopt effective measures to protect the water environment; (3) the environmental assessments and other aspects of IBWT planning should be coordinated; (4) an overall consideration of different basins should be given to achieve a greater range of water resources planning, scheduling, and allocation; and (5) the migration and invasion of species should be of concern during the operation of the project.

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Gillespie, B. R., L. E. Brown et P. Kay. « Effects of Impoundment on Macroinvertebrate Community Assemblages in Upland Streams ». River Research and Applications 31, n^o 8 (6 juin 2014) : 953–63. http://dx.doi.org/10.1002/rra.2785.

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Haggerty, S. M., D. P. Batzer et C. R. Jackson. « Macroinvertebrate response to logging in coastal headwater streams of Washington, U.S.A. » Canadian Journal of Fisheries and Aquatic Sciences 61, n^o 4 (1 avril 2004) : 529–37. http://dx.doi.org/10.1139/f04-014.

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We examined the effects of logging on macroinvertebrate assemblages in first-order streams of four coniferous watersheds in Washington's Coastal Mountain ranges. Each watershed contained three to four first-order streams that were placed into one of three treatment types: clear-cut logging, operational buffer-strip (2.521 m) logging, or uncut reference streams. Prelogging baseline data on macroinvertebrate assemblages, channel morphology, sediment composition, sediment accretion rates, and water temperatures were collected from each stream in summer 1998. Logging operations were conducted the next winter and spring. Streams were resampled in summer 1999, within 1 year of logging, and summer 2000, 1+ years after logging. Preexisting treatment differences did not exist in 1998, indicating that postharvest treatment differences could be attributed to logging operations. In 1999, densities of macroinvertebrate collectors, densities and biomass of macroinvertebrate shredders, and accretion rates of organic sediments were greater in clear-cut and buffered streams than uncut references. These differences diminished by 2000. An increase in collecting and shredding macroinvertebrate is not a typical response to logging and may reflect the fact that logged streams became buried under slash, increasing detrital food supplies for these organisms. The narrow buffers used for this study did not prevent macroinvertebrate community changes associated with logging.

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Bae, Mi-Jung, Jeong-Ki Hong et Eui-Jin Kim. « Evaluation of the Impacts of Abandoned Mining Areas : A Case Study with Benthic Macroinvertebrate Assemblages ». International Journal of Environmental Research and Public Health 18, n^o 21 (22 octobre 2021) : 11132. http://dx.doi.org/10.3390/ijerph182111132.

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Mining activities are among the most long-lasting anthropogenic pressures on streams and rivers. Therefore, detecting different benthic macroinvertebrate assemblages in the areas recovered from mining activities is essential to establish conservation and management plans for improving the freshwater biodiversity in streams located near mining areas. We compared the stability of benthic macroinvertebrate communities between streams affected by mining activities (Hwangjicheon: NHJ and Cheolamcheon: NCA) and the least disturbed stream (Songjeonricheon: NSJ) using network analysis, self-organizing map, and indicator species analysis. Species richness was lowest at sites where stream sediments were reddened or whitened due to mining impacts in NHJ and NCA. Among functional feeding groups, the ratio of scrapers was lower (i.e., NHJ) or not observed (i.e., NCA) in the affected sites by mining. The networks (species interactions) were less connected in NHJ and NCA than in NSJ, indicating that community stability decreased in the area affected by mining activity. We identified five groups based on the similarity of benthic macroinvertebrate communities according to the gradients of mining impacts using a self-organizing map. the samples from the reference stream (clusters 1 and 5), sites located near the mining water inflow area (cluster 4), sites where stream sediments acid-sulfated (cluster 2), and sites that had recovered from mining impacts (cluster 3). Among the 40 taxa selected as indicators defined from the five clusters in self-organizing map, only few (Physa acuta, Tipula KUa, and Nemoura KUb) indicator species were selected in each cluster representing the mining-impacted sites. Our results highlighted that the benthic macroinvertebrate community complexity was lower in streams affected by mining activity. Furthermore, the range of disturbed areas in the streams, where conservation and management plans should be prioritized, can be quantified by examining alterations in the benthic macroinvertebrate community.

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Waddington, Kris I., Jessica J. Meeuwig, Scott N. Evans et Lynda M. Bellchambers. « Assessment of the benthic biota of a deep coastal ecosystem by remote and in situ sampling techniques ». Marine and Freshwater Research 61, n^o 10 (2010) : 1164. http://dx.doi.org/10.1071/mf09273.

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Deep coastal ecosystems (>35 m) occur on the continental shelf of many regions and are poorly understood relative to shallow-water ecosystems. These ecosystems frequently support commercially important benthic-associated species, such as the western rock lobster – the most valuable single-species fishery in Australia. We used remote (towed video) and in situ (diver collection) sampling techniques to investigate the benthic biota of deep coastal ecosystems along the temperate west coast of Australia. We tested the hypotheses that (1) there is no difference in benthic assemblage structure between shallow and deep coastal ecosystems, (2) there is no difference in benthic assemblage structure between locations, and (3) both sampling techniques provide comparable descriptions of benthic assemblages. Deep coastal ecosystems were found to have significant algal and sponge assemblages, suggesting that a reduction in irradiance with depth is not constraining algal distribution. Differences in sponge, algal and macroinvertebrate community composition were detected at a regional scale between study locations. Both sampling techniques identified differences in the composition of benthic assemblages according to location, and yielded similar outcomes with respect to sponge and algal assemblages, suggesting that a single method of habitat classification can be used in future studies to determine broad scale patterns in benthic assemblage composition.

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Trott, Thomas J. « Mesoscale Spatial Patterns of Gulf of Maine Rocky Intertidal Communities ». Diversity 14, n^o 7 (11 juillet 2022) : 557. http://dx.doi.org/10.3390/d14070557.

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Community similarity among macroinvertebrate species assemblages from 12 exposed rocky headlands surveyed in 2004, 2007, and 2012 was examined to resolve mesoscale patterns along an east–west linear distance of 366 km in the coastal Gulf of Maine. The goals were: (1) detect latitudinal patterns of species assemblage similarity and (2) relate species assemblage similarities to environmental factors. Assemblage similarities were correlated with latitude. There was a distinguishable grouping of sampling sites fitting two Gulf regions that separate at mid-coast Maine. This pattern was uniquely intertidal and not shown by subtidal species assemblages. β diversity was high, did not differ between regions, and species turnover accounted for 91% of it. Molluscs and crustaceans, major components of surveyed communities, contributed most of the dissimilarity between regions. Satellite-derived shore and sea surface temperatures explained a significant amount of the variation responsible for producing regional patterns. The regions corresponded with the two principal branches of the Gulf of Maine Coastal Current. These hydrographic features and associated environmental conditions are hypothesized to influence community dynamics and shape the dissimilarity between Gulf regions. The predicted warming of the Gulf of Maine portend change in species turnover from species invasions and range shifts potentially altering rocky intertidal community patterns.

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Doretto, Alberto, Paolo Espa, Francesca Salmaso, Giuseppe Crosa et Silvia Quadroni. « Considering mesohabitat scale in ecological impact assessment of sediment flushing ». Knowledge & ; Management of Aquatic Ecosystems, n^o 423 (2022) : 2. http://dx.doi.org/10.1051/kmae/2021037.

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Benthic macroinvertebrates respond to several factors characterizing the physical habitats, as water depth, current and streambed substrate. Thus, anthropogenic disturbances altering these factors may have different effects on benthos, also depending on mesohabitats. These disturbances include sediment flushing operations, commonly carried out to recover reservoir capacity, and investigating their effects at mesohabitat scale could be relevant for an adequate ecological impact assessment of these operations. Here, we compared benthic macroinvertebrate communities sampled before and after a controlled sediment flushing operation in three different mesohabitats (a pool, a riffle and a step-pool) of an Alpine stream. Contrary from expectations, the composition of macroinvertebrate assemblages was not significantly different among mesohabitats. Moreover, the impact of sediment flushing was more significant in terms of density rather than in richness. Two stressor-specific indices were tested, but only one (the Siltation Index for LoTic EcoSystems − SILTES) clearly detected the impact of sediment flushing on the macroinvertebrate community structure. Finally, some differences in the temporal trajectories and recovery times to pre-flushing conditions were observed among mesohabitats, both if the three mesohabitats were considered separately and if all their possible combinations were accounted for. Particularly, riffle was the most sensitive mesohabitat, not fully recovering one year after the sediment disturbance.

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Bedini, Roberto, Francesca Batistini, Annalisa Nannelli et Luigi Piazzi. « Assessment of anthropogenic disturbance on soft-bottom macroinvertebrate assemblages across different spatial scales ». Journal of the Marine Biological Association of the United Kingdom 92, n^o 3 (30 août 2011) : 439–48. http://dx.doi.org/10.1017/s0025315411001184.

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The present study aimed at evaluating the influence of different gradients of disturbance on the structure of soft-bottom macroinvertebrate assemblages. The following hypotheses were tested: (i) the structure of benthic assemblages does not differ along a gradient of distance from a point-source of pollution; and (ii) this pattern was not influenced by the level of anthropogenic pressure that characterized the area. A combination of multivariate and univariate techniques was used to detect differences in the structure of assemblages among three areas characterized by different environmental conditions, among three distances from point sources of pollution within each area and in two different periods within one year. Differences among conditions in the structure of macroinvertebrate assemblages were evident independently from temporal changes. However, patterns of variability along gradients of disturbance were influenced by the environmental conditions of the studied areas. The total richness was similar in the three studied areas, while beta diversity showed patterns related to both area and distance from point sources of pollution. The results also underlined the suitability of multivariate analysis of the whole community to detect environmental changes.

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Minshall, G. Wayne, Christopher T. Robinson, Deron E. Lawrence, Douglas A. Andrews et James T. Brock. « Benthic macroinvertebrate assemblages in five central Idaho (USA) streams over a 10-year period following disturbance by wildfire ». International Journal of Wildland Fire 10, n^o 2 (2001) : 201. http://dx.doi.org/10.1071/wf01018.

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The effects of wildfire on benthic macroinvertebrate assemblages of streams in mixed-conifer forest were examined for 10 successive years following the Mortar Creek Fire of 1979. Changes in burned-catchment streams were evaluated relative to a paired set of reference-catchment streams. Taxa richness and total abundance tended to be lower in burn than in reference streams but to converge near the end of the study; increases in the final years in both burn and reference streams were associated with reduced flows due to drought. Total biomass and that of the scraper, filterer, and miner functional groups usually were greater in the burn streams. Lack of a strong relationship of macroinvertebrate metrics with weather conditions showed that factors specific to each stream also were influencing the biotic community. Mean among-year Jaccard similarity was lower for burn than for reference streams. Specific taxa responded differently to the effects of fire. Densities of disturbance-adapted forms (e.g. Chironomidae, Baetis) increased after the fire but not during the drought period of more stable flows at the end of the study; many other taxa showed the opposite response. Adverse effects of wildfire on the biotic community were largely the result of physical changes in habitat due to increased runoff. Timing and magnitude of effects differed widely among streams as a result of differences in stream size, burn severity, and specific storm or snow-melt events. Though major effects of the fire on the macroinvertebrates dissipated within 7 years, adjustment in the habitat and biotic conditions still were taking place at the end of 10 year and normal recovery patterns may have been obscured by the drought.

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Kinard, Sean, Christopher J. Patrick et Fernando Carvallo. « Effects of a natural precipitation gradient on fish and macroinvertebrate assemblages in coastal streams ». PeerJ 9 (1 octobre 2021) : e12137. http://dx.doi.org/10.7717/peerj.12137.

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Anthropogenic climate change is expected to increase the aridity of many regions of the world. Surface water ecosystems are particularly vulnerable to changes in the water-cycle and may suffer adverse impacts in affected regions. To enhance our understanding of how freshwater communities will respond to predicted shifts in water-cycle dynamics, we employed a space for time approach along a natural precipitation gradient on the Texas Coastal Prairie. In the spring of 2017, we conducted surveys of 10 USGS-gauged, wadeable streams spanning a semi-arid to sub-humid rainfall gradient; we measured nutrients, water chemistry, habitat characteristics, benthic macroinvertebrates, and fish communities. Fish diversity correlated positively with precipitation and was negatively correlated with conductivity. Macroinvertebrate diversity peaked within the middle of the gradient. Semi-arid fish and invertebrate communities were dominated by euryhaline and live-bearing taxa. Sub-humid communities contained environmentally sensitive trichopterans and ephemeropterans as well as a variety of predatory fish which may impose top-down controls on primary consumers. These results warn that aridification coincides with the loss of competitive and environmentally sensitive taxa which could yield less desirable community states.

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Dalu, Tatenda, Pretty Dlamini, Ryan J. Wasserman, Matjutla J. Mokgoebo, Thendo Mutshekwa, Farai Dondofema et Ross N. Cuthbert. « Effects of environmental variables on littoral macroinvertebrate community assemblages in subtropical reservoirs ». Chemistry and Ecology 37, n^o 5 (9 mars 2021) : 419–36. http://dx.doi.org/10.1080/02757540.2021.1892656.

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Berlajolli, Violeta, Mateusz Płóciennik, Olga Antczak-Orlewska et Vladimir Pešić. « The optimal time for sampling macroinvertebrates and its implications for diversity indexing in rheocrenes − case study from the Prokletije Mountains ». Knowledge & ; Management of Aquatic Ecosystems, n^o 420 (2019) : 6. http://dx.doi.org/10.1051/kmae/2018043.

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In most studies, sampling of springs has typically been undertaken over one season, which has raised the question what the most suitable time(s) to undertake sampling is. In this study, we report the results of macroinvertebrate monthly samplings performed in two springs in western Kosovo in order to determine the most appropriate time to undertake sampling to characterise biodiversity. Diversity indices have revealed that insect assemblages remain more diverse than assemblages of fully aquatic invertebrates. The results of SIMPER have revealed that winter communities remain the most dissimilar one another and also to other seasons. However, when Gammarus balcanicus is excluded, this pattern becomes blurred. To sum up, our results illustrate that (1) multiple surveys covering more than one season provide a comprehensive picture of total biodiversity, and (2) for appropriate characterising of the macroinvertebrate community in the studied rheocrenes at least winter and summer were required.

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Ayoade, A. A., et D. S. Adoh. « Environmental variables and benthic macroinvertebrates of Temidire Stream associated with an oil depot, Ibadan, southwest Nigeria ». Zoologist (The) 20, n^o 1 (25 novembre 2022) : 61–71. http://dx.doi.org/10.4314/tzool.v20i1.8.

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Streams are often recipients of pollution from agricultural, domestic and industrial sources though they are important sources of water supply and habitats of several aquatic species. Regular monitoring is required to protect this fragile but important ecosystem. Therefore, some physico-chemical parameters and macroinvertebrate assemblages of Temidire Stream, a perennial stream that flows through the Nigeria National Petroleum Corporation (NNPC) depot and Temidire community in Apata, Ibadan metropolis were investigated in order to determine the pollution status of the water and sediment and its impact on the biological community. Water and sediment samples were collected from five stations in the stream and from an adjacent stream monthly between August, 2019 and January, 2020 for physico-chemical parameter and benthic macroinvertebrate analyses. Dissolved oxygen, conductivity and total dissolved solids (TDS), and pH were determined in situ using EXTECH EC400 and C933 pH meters, respectively. Heavy metals were determined by atomic absorption spectrophotometry. Benthic macroinvertebrates were collected by kick sampling method. The results showed that TDS and conductivity of station 1 differed significantly from the other stations (p< 0.05). The concentrations of Pb, Ni and Cd exceeded the recommended levels for surface water and Pb and Cd in water and sediment correlated mostly with PC 1. The average Igeo class for the heavy metals in all the stations was >2 indicating uncontaminated to moderately/heavily contaminated sediment. Ninety-six (96) individuals of macroinvertebrates from seven families and six orders were encountered and aquatic insects were dominant (75%). Taxa richness (0-0.82) and diversity (0-0.59) were lower in all the stations compared to the control site. Exceedance of WHO limits by some heavy metals and paucity of macroinvertebrates, especially pollution-sensitive species in the stream suggests that it is polluted. Regular monitoring of the stream is advocated to minimize pollution.

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Lee, Da-Yeong, Dae-Seong Lee et Young-Seuk Park. « Taxonomic and Functional Diversity of Benthic Macroinvertebrate Assemblages in Reservoirs of South Korea ». International Journal of Environmental Research and Public Health 20, n^o 1 (30 décembre 2022) : 673. http://dx.doi.org/10.3390/ijerph20010673.

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Numerous community indices have been developed to quantify the various aspects of communities. However, indices including functional aspects have been less focused on. Here, we examined how community composition varies in response to the environment and discovered the relationship between taxonomic diversity and functional diversity while considering the environment. Macroinvertebrate communities were collected from 20 reservoirs in South Korea. To characterize functional diversity, functional traits in four categories were considered: generation per year, adult lifespan, adult size, and functional feeding groups. Based on their community composition, we classified the reservoirs using hierarchical cluster analysis. Physicochemical and land use variables varied considerably between clusters. Non-metric multidimensional scaling indicated differences between reservoirs and clusters in terms of structure, functional diversity, and environmental variables. A self-organizing map was used to categorize functional traits, and network association analysis was used to unravel relationships between functional traits. Our results support the characteristics of species’ survival strategies such as r- and K-selection. Functional richness exhibited a relationship with taxonomic diversity. Our findings suggest that different types of diversity could play complementary roles in identifying biodiversity. Our findings should prove useful in developing new criteria for assessing freshwater ecosystem health, as well as in evaluating and predicting future alteration of benthic macroinvertebrate communities facing anthropogenic disturbances.

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Desrosiers, Mélanie, Bernadette Pinel-Alloul et Charlotte Spilmont. « Selection of Macroinvertebrate Indices and Metrics for Assessing Sediment Quality in the St. Lawrence River (QC, Canada) ». Water 12, n^o 12 (27 novembre 2020) : 3335. http://dx.doi.org/10.3390/w12123335.

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This study aims to evaluate the anthropogenic pressure in the St. Lawrence River by assessing the relationships between composition and chemical contamination of sediments and macroinvertebrate community structure using a selection of indices and metrics. The aims of this study are to (i) determine the composition of macroinvertebrate community in sediments across a gradient of disturbance, (ii) select relevant macroinvertebrate indices and metrics for the assessment of sediment quality, (iii) investigate whether responses of selected indices and metrics differ across habitats and/or sediment quality classes, and finally, (iv) determine the thresholds for critical contaminants related to significant changes in the most relevant indices and metrics. Organic and inorganic contaminants as well as other sediment variables (sediment grain size, total organic carbon, nutrients, etc.) and macroinvertebrate assemblages were determined in 59 sites along the river. Fourteen macroinvertebrate indices and metrics, on the 264 initially selected, were shown to be the most effective to be used in bioassessment for the St. Lawrence River. However, the variation in macroinvertebrate indices and metrics remains strongly explained by habitat characteristics, such as sediment grain size or the level of nutrients. There is also an influence of metals and, to a lesser extent, organic contaminants such as petroleum hydrocarbons. The 14 selected indices and metrics are promising bioassessment tools that are easy to use and interpret in an environmental assessment of sediment quality in the St. Lawrence River.

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Canning, Adam D. « Predicting New Zealand riverine fish reference assemblages ». PeerJ 6 (28 mai 2018) : e4890. http://dx.doi.org/10.7717/peerj.4890.

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Biomonitoring is a common method to monitor environmental change in river ecosystems, a key advantage of biomonitoring over snap-shot physicochemical monitoring is that it provides a more stable, long-term insight into change that is also effects-based. In New Zealand, the main biomonitoring method is a macroinvertebrate sensitivity scoring index, with little established methods available for biomonitoring of fish. This study models the contemporary distribution of common freshwater fish and then uses those models to predict freshwater fish assemblages for each river reach under reference conditions. Comparison of current fish assemblages with those predicted in reference conditions (as observed/expected (O/E) ratios) may provide a suitable option for freshwater fish biomonitoring. Most of the fish communities throughout the central North Island and lower reaches show substantial deviation from the modelled reference community. Most of this deviation is explained by nutrient enrichment, followed by downstream barriers (i.e. dams) and loss of riparian vegetation. The presence of modelled introduced species had relatively little impact on the presence of the modelled native fish. The maps of O/E fish assemblage may provide a rapid way to identify potential restoration sites.

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Infante, Dana M., J. David Allan, Simon Linke et Richard H. Norris. « Relationship of fish and macroinvertebrate assemblages to environmental factors : implications for community concordance ». Hydrobiologia 623, n^o 1 (2 décembre 2008) : 87–103. http://dx.doi.org/10.1007/s10750-008-9650-3.

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Tibbets, Teresa. « Ten-Years Later : Long-Term Analyses of the Abundance and Biomass of the Non-Native New Zealand Mud Snail and Native Invertebrate Communities in the Greater Yellowstone Area ». UW National Parks Service Research Station Annual Reports 34 (1 janvier 2011) : 147–50. http://dx.doi.org/10.13001/uwnpsrc.2011.3883.

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Invasive species are one of the top two threats to native biodiversity worldwide (Mack et al. 2000). A primary goal of invasion biology is to predict which introduced species become invasive, or reach pest status, and which systems are susceptible to invasion (Heger and Trepl 2003). In order to complete this goal, it is vital to understand long-term dynamics of invasive species populations and their interactions with native communities in their introduced range. Most studies of invasions by non-native species are not extensive enough to determine long-term effects on the native systems (Strayer 2010). The first objective of this study is to determine the long-term abundance and biomass of the New Zealand mud snail, (Potamopyrgus antipodarum), in the Greater Yellowstone Area (GYA). The second objective is to analyze the long-term effects of P. antipodarum on the biomass, abundance, and taxon diversity of native benthic invertebrate assemblages in the GYA. The ten-year span of data available for P. antipodarum and the native macroinvertebrate communities at Lower Polecat Creek in Grand Teton National Park and the Gibbon and Firehole Rivers in Yellowstone National Park provide a unique opportunity to study the macroinvertebrate community succession over time. Data from the proposed macroinvertebrate community survey in the summer of 2011 will be compiled with previous surveys from 2001-2009 to evaluate the long-term changes in the macroinvertebrate community at Polecat Creek and the Gibbon and Firehole Rivers.

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Pinnell, Cassie M., Geana S. Ayala, Melissa V. Patten et Katharyn E. Boyer. « Seagrass and Oyster Reef Restoration in Living Shorelines : Effects of Habitat Configuration on Invertebrate Community Assembly ». Diversity 13, n^o 6 (4 juin 2021) : 246. http://dx.doi.org/10.3390/d13060246.

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Restoration projects provide a valuable opportunity to experimentally establish foundational habitats in different combinations to test relative effects on community assembly. We evaluated the development of macroinvertebrate communities in response to planting of eelgrass (Zostera marina) and construction of reefs intended to support the Olympia oyster (Ostrea lurida) in the San Francisco Estuary. Plots of each type, alone or interspersed, were established in 2012 in a pilot living shorelines project, and quarterly invertebrate monitoring was conducted for one year prior to restoration, and three years post-restoration using suction sampling and eelgrass shoot collection. Suction sampling revealed that within one year, oyster reefs supported unique invertebrate assemblages as compared to pre-restoration conditions and controls (unmanipulated mudflat). The eelgrass invertebrate assemblage also shifted, becoming intermediate between reefs and controls. Interspersing both types of habitat structure led eelgrass invertebrate communities to more closely resemble those of oyster reefs alone, though the eelgrass assemblage maintained some distinction (primarily by supporting gammarid and caprellid amphipods). Eelgrass shoot collection documented some additional taxa known to benefit eelgrass growth through consumption of epiphytic algae; however, even after three years, restored eelgrass did not establish an assemblage equivalent to natural beds, as the eelgrass sea hare (Phyllaplysia taylori) and eelgrass isopod (Pentidotea resecata) remained absent or very rare. We conclude that the restoration of two structurally complex habitat types within tens of meters maximized the variety of invertebrate assemblages supported, but that close interspersion dampened the separately contributed distinctiveness. In addition, management intervention may be needed to overcome the recruitment limitation of species with important roles in maintaining eelgrass habitat.

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Paavo, B. L., D. Ham, S. Görlitz et P. K. Probert. « How does tidal submersion time affect macroinvertebrate community patterns on a temperate sheltered sandflat ? » Marine and Freshwater Research 63, n^o 1 (2012) : 68. http://dx.doi.org/10.1071/mf11147.

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A general model of vertical zonation has been a fruitful foundation of rocky shore ecology, but no analogous model is widely accepted for intertidal soft sediments. Various local proxies have been used for shore height or tidal submersion time, although objective measurements are rare in the literature. In this study, temperature loggers identified submersion period (SP) in a sheltered temperate New Zealand inlet at discrete distances along transect vertical profiles associated with macrofaunal community differences. Our aim was to evaluate this submersion quantification method and determine whether SP described macrofaunal patterns. Despite the patchy presence of engineering species Zostera muelleri and Callianassa filholi, the method was effective in quantifying SP in an inlet with asymmetric tides and SP described spatial macroinvertebrate patterns well. Macrofaunal assemblages corresponded with shore height differences of ~100 mm and SP differences of ~10%. Observations distinguished assemblages submerged less than 30% of the time from those submerged >50% of the time with a continuous community gradient between. We suggest that future intertidal soft-sediment investigations should directly measure SP to: (1) adequately control for this influence when studying more obvious processes with subtle impacts; and (2) further a generic model of soft-sediment zonation.

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Rai, A., D. N. Shah, R. D. T. Shah et C. Milner. « Influence of environmental parameters on benthic macroinvertebrate assemblages in the headwaters of Bagmati river, Kathmandu valley, Nepal ». Banko Janakari 29, n^o 1 (5 août 2019) : 53–61. http://dx.doi.org/10.3126/banko.v29i1.25155.

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The distribution of benthic macro invertebrates (BMIs) is affected by various environmental factors. Understanding their response to these factors is a key to assessing freshwater quality. The aim of this research is to understand the influence of different environmental parameters on BMIs assemblages in the headwaters of Bagmati River. The BMIs were sampled following a multi-habitat sampling protocol and the – hydrological and physico-chemical parameters were measured using standard methods. The relationship between environmental parameters and macro invertebrate assemblages was analyzed through Multivariate analysis - Redundancy Analysis and Variation Partitioning. Stream discharge, pH and Dissolved Oxygen were selected for multivariate analysis through backward elimination method. pH and Dissolved Oxygen were important contributing factors explaining the variation in BMIs community. Physico-chemical parameters were found to be the most important group of variables explaining the variation in macro invertebrate assemblages. Only about twenty-five per cent of the variation in the BMIs community was explained by the model so the parameters studied here do not have a high degree of explanatory power.

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Barrilli, Germano Henrique Costa, Natalia Felix Negreiros, Odete Rocha et José Roberto Verani. « Macroinvertebrates responses based on chemical and physical variables in urban streams ». Papéis Avulsos de Zoologia 61 (27 septembre 2021) : e20216183. http://dx.doi.org/10.11606/1807-0205/2021.61.83.

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The Land uses and occupations around small watersheds generate negative impacts such as deterioration of water quality, environmental simplification, reduced availability of habitats for species, and loss of biodiversity. Benthic macroinvertebrates are an important aquatic community and are widely used in environmental monitoring actions in aquatic ecosystems, including urban streams, which are still little studied in Brazil. In our study, an urban headwater basin (Monjolinho River Basin) was studied on the benthic community structure, together with the physical and chemical variables of the water, as an environmental monitoring tool calculated by RHDEP, TSI, BMWP indexes and abundance-biomass curves. The results showed a gradient of environmental quality, where the best environments are a consequence of preserving the vegetation cover. These environments (Espraiado and Canchim) present groups sensitive to environmental degradation (Ephemeroptera, Plecoptera and Trichoptera), greater diversity and a better structure in the respective benthic macroinvertebrate assemblages. Among the streams sampled, one is very clean, four are moderately polluted, and one is severely polluted. Thus, considering that these streams’ waters are essential for public supply, actions to clean up and recover degraded environments are urgent and a priority.

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Špoljar, Maria, Tvrtko Dražina, Ana Ostojić, Marko Miliša, Marija Gligora Udovič et Dagmar Štafa. « Bryophyte communities and seston in a karst stream (Jankovac Stream, Papuk Nature Park, Croatia) ». Annales de Limnologie - International Journal of Limnology 48, n^o 1 (2012) : 125–38. http://dx.doi.org/10.1051/limn/2011057.

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An investigation into bryophyte communities in karst Jankovac Stream (Papuk Nature Park, Croatia) was carried out once a month from July 2008 to June 2009. Samples were taken from two lotic microhabitats: (i) Jankovac Spring (JS), a hypocrenal habitat with dense bryophyte clusters (90% bottom cover) and (ii) Jankovac Waterfall (JW), with scattered bryophyte clusters (50% bottom cover). At the same time, seston samples were collected during the spring as the source site and after the JW, as the outflow site. The goals of this study were to understand the (i) algal, protozoan and metazoan bryophyte community assemblages in these two lotic microhabitats, (ii) influence of environmental factors on the structuring of the bryophyte community and (iii) structure of seston along the longitudinal profile. A total of 172 taxa were determined: 68 algae, 55 protozoa, 24 meiofauna and 25 macroinvertebrates. Statistically significant differences between two microhabitats differing in percentage of bryophyte cover were established testing 13 environmental parameters. In dense bryophyte clusters, community structure was determined by flow velocity and pH, and macroinvertebrates achieved higher diversity and abundance. On the contrary, in scattered bryophyte coverage algae, protozoa and meiofauna reached higher abundance and diversity governed by the amount of suspended organic matter and epiphyton. In contrast to previous studies, the inverse ratio of community diversity and abundanceversuspercentage of bryophyte cover was established. We assume this to be the result of an enrichment of the scattered bryophyte clusters by upstream seston. Additionally, the effects of anthropogenic hydromorphological disturbance are reflected in macroinvertebrate diversity and abundance reduction.

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Milner, Victoria S., Nigel J. Willby, David J. Gilvear et Charles Perfect. « Linkages between reach-scale physical habitat and invertebrate assemblages in upland streams ». Marine and Freshwater Research 66, n^o 5 (2015) : 438. http://dx.doi.org/10.1071/mf14008.

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Determining the influence of physical habitat on biological structure in minimally disturbed settings is important if the effects of alterations to physical habitat are to be understood. This study tested whether reach-scale differences in physical habitat influence macroinvertebrate community composition at 24 sites in the Cairngorm Mountains, Scotland. Stream reaches were classified into channel types based on a geomorphic typology (i.e. step-pool, bedrock, plane-bed and pool-riffle). PERMANOVA indicated an overall significant relationship between the geomorphic typology and macroinvertebrate species-level composition, and among all combinations of channel types (such as step-pool and pool-riffle, step-pool and bedrock). Most channel types were dominated by high abundances of Baetis rhodani, Rhithrogena semicolorata and Leuctra inermis, which are ubiquitous in unpolluted gravel-bedded Scottish streams. However, reflecting significant differences in abundance of commoner taxa between types, indicator value (IndVal) analysis revealed that pool-riffle reaches were characterised by elmids (Limnius sp. and Oulimnius sp.) and Caenis rivulorum, and step-pool reaches by Alainites muticus, B. rhodani, L. inermis and Brachyptera risi. Geomorphic typing of rivers provides a useful basis for the initial assessment of ecological status whereas abundance-based biological data processed at the appropriate taxonomic resolution should be sensitive to physical-habitat modifications.

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Maitland, Victoria Carley, Chloe Victoria Robinson, Teresita M. Porter et Mehrdad Hajibabaei. « Freshwater diatom biomonitoring through benthic kick-net metabarcoding ». PLOS ONE 15, n^o 11 (18 novembre 2020) : e0242143. http://dx.doi.org/10.1371/journal.pone.0242143.

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Biomonitoring is an essential tool for assessing ecological conditions and informing management strategies. The application of DNA metabarcoding and high throughput sequencing has improved data quantity and resolution for biomonitoring of taxa such as macroinvertebrates, yet, there remains the need to optimise these methods for other taxonomic groups. Diatoms have a longstanding history in freshwater biomonitoring as bioindicators of water quality status. However, multi-substrate periphyton collection, a common diatom sampling practice, is time-consuming and thus costly in terms of labour. This study examined whether the benthic kick-net technique used for macroinvertebrate biomonitoring could be applied to bulk-sample diatoms for metabarcoding. To test this approach, we collected samples using both conventional multi-substrate microhabitat periphyton collections and bulk-tissue kick-net methodologies in parallel from replicated sites with different habitat status (good/fair). We found there was no significant difference in community assemblages between conventional periphyton collection and kick-net methodologies or site status, but there was significant difference between diatom communities depending on site (P = 0.042). These results show the diatom taxonomic coverage achieved through DNA metabarcoding of kick-net is suitable for ecological biomonitoring applications. The shift to a more robust sampling approach and capturing diatoms as well as macroinvertebrates in a single sampling event has the potential to significantly improve efficiency of biomonitoring programmes that currently only use the kick-net technique to sample macroinvertebrates.

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Sueiro, María Cruz, Alejandro Bortolus et Evangelina Schwindt. « Habitat complexity and community composition : relationships between different ecosystem engineers and the associated macroinvertebrate assemblages ». Helgoland Marine Research 65, n^o 4 (27 novembre 2010) : 467–77. http://dx.doi.org/10.1007/s10152-010-0236-x.

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Bououarour, Oussama, Soilam Boutoumit, Reda El Kamcha et Hocein Bazairi. « Latitudinal Variation into the Macrofaunal Assemblages Associated to Zostera noltei Seagrass along the Atlantic Coast of Morocco ». International Journal of Zoology 2021 (18 octobre 2021) : 1–15. http://dx.doi.org/10.1155/2021/9199654.

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Large-scale research on seagrass-associated benthic fauna is very important for future regional marine conservation. In our study, we investigated spatial and latitudinal variation of benthic macroinvertebrate assemblages associated to Zostera noltei Hornemann, 1832 beds from five semi-enclosed coastal systems (SECSs) ranging from 23°N to 34°N along the Atlantic coast of Morocco. Overall, 17,320 individuals were reported as belonging to 96 taxa. The ecological community descriptors differ significantly at the level of the site. Specific richness showed an inconsistent significant pattern with latitude. The multivariate analyses of the assemblage’s composition showed 57% of total variation observed in benthic assemblages, while the PERMANOVA analysis confirmed that this variation is significant at the level of the site. According to DistLM results, variations in belowground biomass, and percentage of mud, were the important predictor variables explaining this variation along the large scale of the studied SECS. However, such patterns could be related to other factors such as habitat heterogeneity and regional, biogeographic, and anthropogenic factors. The present study marked the first attempt on broad-scale ecological research of seagrass beds in Morocco and offers baseline data for planning the broad-scale conservation of biodiversity in seagrass beds that remain suffering from multiple human-induced threats such as coastal developments and climate change.

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Popovic, Natasa, Jelena Djuknic, Jelena Canak-Atlagic, Maja Rakovic, Bojana Tubic, Stefan Andjus et Momir Paunovic. « The relation between chironomid (Diptera : Chironomidae) assemblages and environmental variables : The Kolubara River case study ». Archives of Biological Sciences 68, n^o 2 (2016) : 405–15. http://dx.doi.org/10.2298/abs150521123p.

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Chironomid larvae respond rapidly to environmental changes in aquatic ecosystems, with different species possessing different degrees of tolerance. Consequently, this group is considered an effective and reliable indicator of the ecological status. In this study, the relation between larval chironomid assemblages and environmental variables was examined at two sites on the Kolubara River. The nonparametric Mann-Whitney U test did not confirm significant seasonal differences between samples. Correspondence analysis indicated that the study sites are distinguished by their community composition. Based on forward selection analyses, 5 out of the 28 analyzed water parameters and 3 out of the 22 sediment parameters displayed the highest levels of correlation with chironomid assemblages. Forward selection analysis revealed that inorganic pollutants in the sediment (mercury, nickel and cadmium) exerted the greatest influence on the community. Results of canonical correspondence analysis indicated that the sediment characteristics have a more significant impact on chironomid communities than the analyzed water parameters. Our study confirmed that chironomids and sediment analyzes should be obligatorily included in the monitoring of ecological status, since chironomids are often a dominant component of benthic macroinvertebrate assemblages in freshwater ecosystems, with many species inhabiting the sediment with a proclivity for intake of toxic and persistent pollutants.

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Gjoni, Vojsava, et Douglas Stewart Glazier. « A Perspective on Body Size and Abundance Relationships across Ecological Communities ». Biology 9, n^o 3 (26 février 2020) : 42. http://dx.doi.org/10.3390/biology9030042.

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Recently, several studies have reported relationships between the abundance of organisms in an ecological community and their mean body size (called cross-community scaling relationships: CCSRs) that can be described by simple power functions. A primary focus of these studies has been on the scaling exponent (slope) and whether it approximates −3/4, as predicted by Damuth’s rule and the metabolic theory in ecology. However, some CCSR studies have reported scaling exponents significantly different from the theoretical value of −3/4. Why this variation occurs is still largely unknown. The purpose of our commentary is to show the value of examining both the slopes and elevations of CCSRs and how various ecological factors may affect them. As a heuristic exercise, we reanalyzed three published data sets based on phytoplankton, rodent, and macroinvertebrate assemblages that we subdivided according to three distinctly different ecological factors (i.e., climate zone, season, and trophic level). Our analyses reveal significant variation in either or both the CCSR slopes and elevations for marine phytoplankton communities across climate zones, a desert rodent community across seasons, and saltwater lagoon macroinvertebrate communities across trophic levels. We conclude that achieving a comprehensive understanding of abundance-size relationships at the community level will require consideration of both slopes and elevations of these relationships and their possible variation in different ecological contexts.

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Motitsoe, Samuel N., Julie A. Coetzee, Jaclyn M. Hill et Martin P. Hill. « Biological Control of Salvinia molesta (D.S. Mitchell) Drives Aquatic Ecosystem Recovery ». Diversity 12, n^o 5 (21 mai 2020) : 204. http://dx.doi.org/10.3390/d12050204.

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Salvinia molesta D.S. Mitchell (Salviniaceae) is a damaging free-floating invasive alien macrophyte native to South America. The biological control programme against S. molesta by the weevil Cyrtobagous salviniae Calder and Sands (Erirhinidae) has been successful in controlling S. molesta infestations in the introduced range, however, there is some debate as to how biological control success is measured. This study measured the response of epilithic algae and aquatic macroinvertebrate communities in a S. molesta-dominated state and subsequently where the weed had been cleared by biological control, as a proxy for ecosystem recovery in a before–after control–impact mesocosm experiment. The restored treatment (S. molesta and C. salviniae) demonstrated epilithic algae and aquatic macroinvertebrate recovery during the “after” biological control phase, defined as similar to the control treatment. Comparatively, the impacted treatment (100% S. molesta) showed a drastic decline in biodiversity and shifts in community assemblages. We conclude that the biological control effort by C. salviniae facilitated biodiversity recovery of the impacted treatment. Furthermore, epilithic algae and aquatic macroinvertebrate communities were reliable biological indicators for measuring ecological impacts of invasion and ecosystem recovery following biological control, and thus represent potential tools for evaluating biological control success and ecological restoration.

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Moore, Isabel Eleanor, et Kevin Joseph Murphy. « Evaluation of alternative macroinvertebrate sampling techniques for use in a new tropical freshwater bioassessment scheme ». Acta Limnologica Brasiliensia 27, n^o 2 (juin 2015) : 213–22. http://dx.doi.org/10.1590/s2179-975x8813.

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Aim: The study aimed to determine the effectiveness of benthic macroinvertebrate dredge net sampling procedures as an alternative method to kick net sampling in tropical freshwater systems, specifically as an evaluation of sampling methods used in the Zambian Invertebrate Scoring System (ZISS) river bioassessment scheme. Tropical freshwater ecosystems are sometimes dangerous or inaccessible to sampling teams using traditional kick-sampling methods, so identifying an alternative procedure that produces similar results is necessary in order to collect data from a wide variety of habitats.MethodsBoth kick and dredge nets were used to collect macroinvertebrate samples at 16 riverine sites in Zambia, ranging from backwaters and floodplain lagoons to fast flowing streams and rivers. The data were used to calculate ZISS, diversity (S: number of taxa present), and Average Score Per Taxon (ASPT) scores per site, using the two sampling methods to compare their sampling effectiveness. Environmental parameters, namely pH, conductivity, underwater photosynthetically active radiation (PAR), temperature, alkalinity, flow, and altitude, were also recorded and used in statistical analysis. Invertebrate communities present at the sample sites were determined using multivariate procedures.ResultsAnalysis of the invertebrate community and environmental data suggested that the testing exercise was undertaken in four distinct macroinvertebrate community types, supporting at least two quite different macroinvertebrate assemblages, and showing significant differences in habitat conditions. Significant correlations were found for all three bioassessment score variables between results acquired using the two methods, with dredge-sampling normally producing lower scores than did the kick net procedures. Linear regression models were produced in order to correct each biological variable score collected by a dredge net to a score similar to that of one collected by kick net sampling.ConclusionsThe use of a dredge net in macroinvertebrate bioassessment schemes is an effective, alternative method in certain environments when site conditions prohibit the use of the preferred kick net sampling method. The results of this study can be used to aid in the development of other tropical freshwater bioassessment schemes around the world, including Brazil.

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Moreno-Ocio, Iñigo, Leire Méndez-Fernández, Maite Martínez-Madrid, Noemí Costas, Isabel Pardo et Pilar Rodriguez. « Developing As and Cu Tissue Residue Thresholds to Attain the Good Ecological Status of Rivers in Mining Areas ». Archives of Environmental Contamination and Toxicology 82, n^o 3 (4 mars 2022) : 379–90. http://dx.doi.org/10.1007/s00244-022-00915-w.

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AbstractThe study was performed on residue-effects datasets from polluted and unpolluted sites in the Nalón River basin (northern Spain). The effects were measured in terms of alteration of field macroinvertebrate communities, and measured as ecological status scores, and number of families and abundance of Ephemeroptera, Plecoptera and Trichoptera (EPT). Non-linear regression models of the field-measured tissue residues in 10 taxa related to the ecological status of the macroinvertebrate communities were used to derive effective tissue residues (ERs). These were estimated for the good/moderate boundary defined by the ecological quality ratio (EQRs) score and for the 50% reduction of EQR and EPT metrics. As, Cu, Hg and Se ERs were calculated for several macroinvertebrate taxa with different feeding styles. The ER dataset allowed us to estimate As and Cu hazardous concentrations (HC), using species sensitivity distribution models, and were interpreted as community thresholds. Further studies for Hg and Se are needed to complete the database required for HC estimation. The reliability and differences of the several thresholds were tested in a risk assessment using a tissue-residue approach (TRA) conducted with field organisms from Cauxa Creek, a tributary from the same basin exposed to high levels of metals in the sediments due to gold mining activities. This risk assessment identified that As and Cu tissue residues satisfactorily explained the reduction in the ecological status of the macroinvertebrate assemblages. Our results indicate that TRA can help in setting future environmental quality standards for the protection of aquatic biota. Graphical Abstract

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Suriano, Marcia Thais, et Alaide Aparecida Fonseca-Gessner. « Structure of benthic macroinvertebrate assemblages on a gradient of environmental integrity in Neotropical streams ». Acta Limnologica Brasiliensia 25, n^o 4 (décembre 2013) : 418–28. http://dx.doi.org/10.1590/s2179-975x2013000400007.

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AIM: This study investigated the taxonomic composition of the benthic macroinvertebrates in streams to evaluate how this fauna reflects the various uses of the soil and to identify which groups of macroinvertebrates might be taken as characterizing each situation under study. METHODS: To achieve these objectives, 29 streams were collected and inserted in regions with different conservation using Surber sampler. Analyzes were performed of environmental variables (Principal Components Analysis - PCA) and taxonomic structure of the community (taxon richness, numerical abundance and Multidimensional scaling - MDS). RESULTS: EPT group (orders Ephemeroptera, Plecoptera and Trichoptera) and the Coleoptera exhibited greater numerical abundance and taxon richness in streams located in reference areas. In contrast, dipteran larvae, especially the chironomids, along with immature odonates, were more abundant in streams in areas suffering from a lack of riparian forest. Multidimensional scaling analysis (MDS) revealed an environmental gradient, on which the streams within the Atlantic forest formed a tightly clustered group, as did those in semideciduous forests. However, the latter group occupied an intermediate position between the Atlantic forest streams and those in areas disturbed by human activity. Among these areas there were no specific clusters by monoculture. CONCLUSIONS: Among the groups of streams defined by the types of land use in the adjacent areas, the state of integrity was found to decline from Atlantic rainforest, through semi-deciduous forest and then pasture, to the monocultures of eucalypts and sugarcane.

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Baumart, Joele, Marcelo Dalosto et Sandro Santos. « Effects of carbofuran and metsulfuron-methyl on the benthic macroinvertebrate community in flooded ricefields ». Acta Limnologica Brasiliensia 23, n^o 2 (juin 2011) : 138–44. http://dx.doi.org/10.1590/s2179-975x2011000200004.

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AIM: This study evaluated the effect of the insecticide carbofuran and the herbicide metsulfuron-methyl on the abundance and diversity of benthic macroinvertebrates in a paddy ricefield. METHODS: To achieve this goal, two pesticide treatments [the insecticide carbofuran (IC) and the herbicide metsulfuron-methyl (HM)] and a control (Co) treatment with no added pesticide were established in an experimental area of the Plant Science Department of the Federal University of Santa Maria. Soil samples were collected in triplicate from each treatment 30 days before and 1, 10, and 51 days after the pesticide application, for macrofauna identification. RESULTS: Among the 21 taxa identified, Trichoceridae was present only in Co, Hydroptilidae was recorded only in IC, and Corixidae in HM. In Co, the most abundant group was Annelida, while in IC and HM Diptera (Chironomidae) was dominant. Significant differences were observed between Co and IC, in the density of Odontoceridae (Control>IC) and Hydrophilidae (Control<IC), and between Co and HM in the density of Odontoceridae (Control>HM) and Hirudinea (Control<HM). CONCLUSION: In spite of the possible negative effects of the pesticides on the benthic community, the assemblages recovered rapidly.

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Huryn, Alexander D., Karie A. Slavik, Rex L. Lowe, Stephanie M. Parker, Dennis S. Anderson et Bruce J. Peterson. « Landscape heterogeneity and the biodiversity of Arctic stream communities : a habitat template analysis ». Canadian Journal of Fisheries and Aquatic Sciences 62, n^o 8 (1 août 2005) : 1905–19. http://dx.doi.org/10.1139/f05-100.

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We predicted that substratum freezing and instability are major determinants of the variability of stream community structure in Arctic Alaska. Their effects were conceptualized as a two-dimensional habitat template that was assessed using a natural experiment based on five stream types (mountain-spring, tundra-spring, tundra, mountain, glacier). Detrended correspondence analysis (DCA) indicated distinct macroinvertebrate assemblages for each stream type. The contribution of functional feeding groups to assemblage biomass varied systematically among stream types, indicating that structure and function are linked. Assemblage position within a DCA biplot was used to assess factors controlling its structure. Springs separated from other stream types along a gradient of nutrient concentration and freezing probability. Glacier and mountain streams separated from springs and tundra streams along a gradient of substratum instability and freezing probability. Owing to differences in sources of discharge to streams, the effects of nutrients and substratum stability could not be separated from freezing. Although many factors likely contribute to the variability of Arctic stream communities, the major determinants may be conceptualized as a template structured by gradients in (i) nutrient supply and substratum freezing and (ii) substratum instability and substratum freezing. This template provides a basis for predicting the response of Arctic stream communities to climate change.

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Snyder, Craig D., John A. Young, David P. Lemarié et David R. Smith. « Influence of eastern hemlock (Tsuga canadensis) forests on aquatic invertebrate assemblages in headwater streams ». Canadian Journal of Fisheries and Aquatic Sciences 59, n^o 2 (1 février 2002) : 262–75. http://dx.doi.org/10.1139/f02-003.

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We conducted a comparative study in the Delaware Water Gap National Recreation Area to determine the potential long-term impacts of hemlock forest decline on stream benthic macroinvertebrate assemblages. Hemlock forests throughout eastern North America have been declining because of the hemlock woolly adelgid, an exotic insect pest. We found aquatic invertebrate community structure to be strongly correlated with forest composition. Streams draining hemlock forests supported significantly more total taxa than streams draining mixed hardwood forests, and over 8% of the taxa were strongly associated with hemlock. In addition, invertebrate taxa were more evenly distributed (i.e., higher Simpson's evenness values) in hemlock-drained streams. In contrast, the number of rare species and total densities were significantly lower in streams draining hemlock, suggesting that diversity differences observed between forest types were not related to stochastic factors associated with sampling and that streams draining mixed hardwood forests may be more productive. Analysis of stream habitat data indicated that streams draining hemlock forests had more stable thermal and hydrologic regimes. Our findings suggest that hemlock decline may result in long-term changes in headwater ecosystems leading to reductions in both within-stream (i.e., alpha) and park-wide (i.e., gamma) benthic community diversity.

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ZHIVOGLYADOVA, LYUBOV L., et VYACHESLAV S. LABAY. « Caddisflies (Trichoptera) in benthic communities of southern Sakhalin rivers, Far East Russia ». Zoosymposia 10, n^o 1 (9 août 2016) : 493–501. http://dx.doi.org/10.11646/zoosymposia.10.1.44.

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During one year we studied caddisfly assemblages in benthic macroinvertebrate communities of mountain (Frikena River) and piedmont (Partizanka River) reaches of the Lyutoga River Basin. For most of the year in the mountain reaches, the scraper Neophylax ussuriensis Martynov dominates. Maximum caddisfly density (403 ind./m2) and biomass (14,441 g/m2) was recorded in July before mass emergence of that dominant species. The density of caddisflies in the benthic community was more significant in November (32%), and caddisfly biomass was most significant in July (69%). In the piedmont reaches of Lyutoga River Basin in various seasons, Rhyacophila (Hyporhyacophila) sp., Hydatophylax sp., Hydropsyche orientalis Martynov, and Stenopsyche marmorata Navás dominated. Maximum density and biomass of caddisflies (451 ind./m2, 1,576 g/m2) were recorded in 5 September. The density of filterers H. orientalis and S. marmorata occurs in the salmon spawning season and seems to be correlated with the increased abundance of suspended organic substances in the water column as salmon spawn. In the piedmont reaches the role of caddisflies are the most significant in September (49% of total macroinvertebrate density and 56% of biomass).

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Jurajda, P., Z. Adámek, M. Janáč et Z. Valová. « Longitudinal patterns in fish and macrozoobenthos assemblages reflect degradation of water quality and physical habitat in the Bílina river basin ». Czech Journal of Animal Science 55, No. 3 (24 mars 2010) : 123–36. http://dx.doi.org/10.17221/14/2009-cjas.

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The aim of this study was to provide the first account of fish and macroinvertebrate communities in a heavily degraded river basin in the Czech Republic. Fish and macrozoobenthos were surveyed at 18 sites in the Bílina River and 11 sites in tributary streams during June–July 2007. Fish were sampled by electrofishing and macrozoobenthos were collected by kick-sampling using a sweep net. The composition of macroinvertebrate assemblages in headwater and reference sites in the upper Bílina River indicated clean water with saprobic index (SI) 1.31–1.43 followed by a transitional stretch downstream the Kyjická reservoir (SI 2.05–2.32) and dramatic decline of water quality to SI 3.18 in the river stretch downstream of industrial and municipal pollution at Litvínov-Záluží. Despite several minor pollution sources on the subsequent downstream river stretch until its mouth into the Elbe River, the water quality indicators fluctuated in the range of lower betamesosaprobity (SI 2.06–2.58). Species richness and biodiversity indices followed a similar pattern as river saprobity. Twenty-three fish species were documented in the Bílina River basin. Chub (Leuciscus cephalus), gudgeon (Gobio gobio) and roach (Rutilus rutilus) were the most frequent species at the Bílina sites. Chub was the most numerous fish in the tributaries. Fish species richness in the longitudinal profile did not increase downstream in the Bílina mainstem, most likely because the presence of reservoirs and water pollution interrupted the river continuum pattern. Qualitative data on fish assemblages corresponded to the course of environmental stress. A sustainable fish community was documented only in the lowermost site in Ústí nad Labem near the confluence with the Elbe River. The Bílina River tributaries constitute potential refuges for fish in this basin.

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Rabaoui, Lotfi, Radhouane El Zrelli, Mohammed Ben Mansour, Rafik Balti, Lamjed Mansour, Sabiha Tlig-Zouari et Mokhtar Guerfel. « On the relationship between the diversity and structure of benthic macroinvertebrate communities and sediment enrichment with heavy metals in Gabes Gulf, Tunisia ». Journal of the Marine Biological Association of the United Kingdom 95, n^o 2 (16 octobre 2014) : 233–45. http://dx.doi.org/10.1017/s0025315414001489.

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The variations in the composition and structure of macroinvertebrate benthic communities in relationship with the marine sediment enrichment with heavy metals were investigated in the Gulf of Gabes, Tunisia. Standard community parameters as well as the trophic and ecological structure were analysed in 18 stations sampled in six localities. Highest values of diversity descriptors (S, N and H′) were recorded in the less-polluted localities and vice versa. Besides, the results of AMBI and BENTIX indexes were also concordant with those obtained with the classical diversity parameters and matched with the sediment heavy metals distribution in the Gulf of Gabes. Compared with the northern and southern parts of the Gulf, the central area was found to be the most polluted and to host the most-affected benthic community. In addition, biotic indexes were found to be very useful tools to monitor the ecological quality status of benthic assemblages.

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Taybi, Abdelkhaleq Fouzi, Youness Mabrouki, Mohamed Dakki, Ali Berrahou et Andrés Millán. « Longitudinal distribution of macroinvertebrate in a very wet North African Basin : Oued Melloulou (Morocco) ». Annales de Limnologie - International Journal of Limnology 56 (2020) : 17. http://dx.doi.org/10.1051/limn/2020016.

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Melloulou River, which is located in Middle Atlas of Morocco, is a good example of a very wet and poorly known basin, and therefore of special conservation concern. The aim of this study was to draw up an initial inventory of the benthic macroinvertebrates taxa, and to analyze its longitudinal distribution in the basin, particularly searching for the main abiotic factors addressing its zonation for improving future management and conservation actions. The study allowed identifying 161 taxa belonging to 127 genera and 80 families, most new records for northeast Morocco. The biotypology, which was studied by using Foucart' Factorial Correspondence Analysis (FCA), Partial Triadic analysis (PTA), and IndVal showed a longitudinal distribution of macroinvertebrates mainly governed by altitude, slope and current velocity. The studied biota revealed the presence of three assemblages and an important number of ubiquitous species not included in any group. The first group is located in the upper courses of Melloulou River representing a community proper of a crenon-rhithron zone; the second occurs in the middle and lower courses, and clearly reflects the community of a large potamon; the third one is a mixture of taxa capable to colonize the entire study area. Our finding, highlight the singular aquatic biodiversity occurring in the Melloulou River and its extraordinary changing water dynamic over time, which are key factors for future monitoring, as well as managing and conservation actions.

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Friberg, N., A. Baattrup-Pedersen, E. A. Kristensen, B. Kronvang, S. E. Larsen, M. L. Pedersen, J. Skriver, H. Thodsen et P. Wiberg-Larsen. « The River Gelså restoration revisited : Habitat specific assemblages and persistence of the macroinvertebrate community over an 11-year period ». Ecological Engineering 66 (mai 2014) : 150–57. http://dx.doi.org/10.1016/j.ecoleng.2013.09.069.

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Barbero, María Daniela, Ana María Oberto et Cristina Mabel Gualdoni. « Spatial and temporal patterns of macroinvertebrates in drift and on substrate of a mountain stream (Cordoba, Central Argentina) ». Acta Limnologica Brasiliensia 25, n^o 4 (décembre 2013) : 375–86. http://dx.doi.org/10.1590/s2179-975x2013000400003.

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AIMS: The aims of this study are to evaluate the effects of spatial and temporal variability of the macroinvertebrate fauna in drift and in the substrate of a mountain stream. METHODS: The study site is located in Achiras stream (Central, Argentina). This is an endorheic fluvial course whose headwaters are located in the southern extreme of Los Comechingones Mountains. Three replicate Surber samples were collected from benthos with 300 µm, 0.09 m² nets. Three drifting fauna samples were collected using drift nets, 1 m long, 300 µm and 0.0192 m². The taxonomic identification of specimens was performed according to the lowest possible taxonomic level. In order to characterize the drifting and benthic fauna, total abundance, taxonomic richness, Shannon and evenness indices were estimated and they were tested with two-way analysis of variance (ANOVA). In order to assess the distribution patterns of drift and benthos samples, we performed Canonical Correspondence Analysis (CCA). RESULTS: A total of 61 taxa were identified in drift and 82 in benthos. A 26.3% taxonomic similarity between the two assemblages was observed, according to the Jaccard index. In drift and benthos, Arthropoda presented higher abundance and Insecta contributed with more taxa and it was also the most abundant. The most abundant orders were Ephemeroptera, Trichoptera and Diptera. In the present study, Anacroneuria sp. (Perlidae) and Podonominae (Chironomidae) were first recorded for benthic community of Achiras stream. CONCLUSION: In this study we found that the structural organization of the drifting and benthic macroinvertebrate community shows different patterns of variation at spatial and temporal scales.

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