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Reduction of sampling effort assessing macroinvertebrate assemblages for biomonitoring of rivers

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Abstract

Biomonitoring methods based on macroinvertebrate assemblages are widely developed in streams and rivers. However, the use of invertebrates has been criticized due to the long time and expense of processing samples. Therefore, we evaluated the effectiveness of reducing the sampling effort from 20 to 5 samples to assess the stream macroinvertebrate community. In six streams in the Basque Country (North of Spain) 20 kick nets were collected following a multihabitat stratified sampling design. The macroinvertebrates were identified to family level and a smoothed family accumulation curve fitting the Clench function to the data was calculated for each stream. Richness was lower in 5 than in 20 samples. However, in general, the percentage of richness estimated with the subsampling may be considered representative of the existing taxa richness. Therefore, the study of five samples may be adequate for biomonitoring Basque streams, greatly minimizing time, effort and costs. RÉSUMÉ

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... For example, Carlisle et al. (2008) showed that the macroinvertebrate model was the most precise compared to the diatom and fish models. However, the use of macroinvertebrates has been criticized due to long-time requirements and expensive costs of sampling, sorting, counting, and identifying them (De Bikuna et al., 2015) and this is likely to affect the effectiveness of biomonitoring protocols using macroinvertebrate communities (Pinna et al., 2014). ...
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Streams and rivers cover a larger proportion of the Earth’s surface but are highly affected by human pressures. Conversely, bioassessment methods are in their infancy in developing countries such as Ethiopia. In this study, we compared 2- and 3-min macroinvertebrate kick samples at multiple locations for both riffle habitat (RH) and multihabitat (MH) approaches. The performance of each method was evaluated statistically using benthic macroinvertebrate metrics and diversity indices. Results of the Kruskal–Wallis analysis in this study showed no significant differences among methods tested in minimally impacted streams in Ethiopia and generally performed equally irrespective of the methods employed except for total abundances and Ephemeroptera abundances. Furthermore, multivariate analysis of the relative abundances of macroinvertebrate communities using analysis of similarity (ANOSIM), RELATE, non-metric multidimensional scaling (MDS), and classification strength-sampling method comparability (CS-SMC) indicated a high similarity in the macroinvertebrate communities recorded among all methods employed in this study area. However, the index of multivariate dispersion (IMD) test showed variations in relative abundances of macroinvertebrate communities among the methods. In summary, if the focus is not on rare taxa and the required information is not dependent on additional evidence provided by the use of lower taxonomic levels of identification (genus and species), the results of the present study support the use of the shorter 2-min RH kick sampling method for the bioassessment of wadeable rivers and streams in Ethiopia.
... Benthic macroinvertebrates were collected from undisturbed shallow runs and riffles using a Surber sampler (20 × 20 cm and 250 µm mesh net) and stored in plastic bottles containing 70% ethanol. We used eight replicates for each sampling site because this amount of sampling effort is considered sufficient to characterise macroinvertebrate communities (Gartzia De Bikuña et al. 2015). In the laboratory, benthic macroinvertebrates were counted and identified to family under a dissecting microscope. ...
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The stress-gradient hypothesis predicts that biotic interactions within food webs are context dependent, since environmental stressors can attenuate consumer–prey interactions. Yet, how heavy metal pollution influences the impacts of predatory fish on ecosystem structure is unknown. This study was conducted in the Osor stream (Spain), which features a metal (mainly Zn) pollution gradient. We aimed to determine how the responses of benthic communities to the presence and absence of predatory fish interact with environmental stress and to test whether the top-down control of top predators is context dependent. To address these questions, periphyton biomass and macroinvertebrate densities were determined throughout an exclosure/enclosure mesocosm experiment using the Mediterranean barbel (Barbus meridionalis) as a top predator. The monitoring study showed that metal accumulation in periphyton and macroinvertebrates reflected patterns observed in water. The mesocosm study showed that fish predation effects on larval chironomids were not context-dependent and that periphyton biomass was markedly lower in the presence of fish regardless of metal pollution levels. This strong top-down control on periphytic algae was attributed to the foraging behaviour of fish causing bioturbation. In contrast, the top predator removal revealed grazer-periphyton interactions, which were mediated by heavy metal pollution. That is, periphyton benefitted from a lower grazing pressure in the metal-polluted sites. Together, our results suggest that the top–down control by fishes depends more on functional traits (e.g. feeding behaviour) than on feeding guild, and demonstrate the capacity of top predators to modify anthropogenic stressor effects on stream food-web structure.
... Benthic macroinvertebrates were collected from undisturbed shallow runs and riffles using a Surber sampler (20 × 20 cm and 250 µm mesh net) and were stored in plastic bottles containing 70% ethanol. We used eight replicates for each sampling site because this amount of sampling effort is considered sufficient to characterise macroinvertebrate communities (Gartzia De Bikuña et al. 2015). In the laboratory, benthic macroinvertebrates were counted and identified to family under a dissecting microscope. ...
Thesis
Community structure and ecosystem functions are determined by physical and chemical conditions, food resources and biotic interactions. Mediterranean-climate streams are intrinsically variable in streamflow, with marked flow reduction in summer and floods in autumn and spring according to regional precipitation patterns. Riverine species are adapted to cope with natural and predictable disturbances, and their responses are in a large part determined by their physiological and behavioral adaptations. As for fish, swimming performance can determine their ability to use habitats differing in water velocity, to obtain food and avoid predation, etc. Today, the intense use of water by human demands causes longer low-flow periods in streams, thereby producing a certain degree of water stress. In addition, nutrient enrichment and water pollution are also common anthropogenic stressors that threaten ecological integrity of freshwater ecosystems. Metal pollution is of particular concern due to its high potential toxicity, perdurability and bioaccumulation through the food chain. At the bottom of the food chain, periphyton communities serve as food and energy sources for many organisms (e.g. macroinvertebrate grazers), so any stressor affecting periphyton is likely to indirectly affect organisms of a higher trophic level (“bottom-up control”). On the contrary, periphytic algal biomass can be affected by shifts in grazing pressure, e.g. resulting from predator-induced changes in grazer density (“top-down control”). Periphyton communities are also involved in important ecosystem functions (e.g. nutrient cycling), and are important bioindicators for habitat degradation. Field mesocosm experiments, from which we can modify the density of certain consumers (e.g. fishes), have become an invaluable tool in ecotoxicology and ecology for increasing mechanistic understanding of stressor effects. This thesis aimed to assess the responses of stream biota to flow alterations, in terms of water velocity increments and reductions of discharge, and to metal pollution. The investigations performed encompassed (i) respirometry studies using swim-tunnel respirometers to evaluate swimming capabilities, as indicative of water velocity tolerance, and physiological responses (energetic costs of swimming) of several freshwater fishes, as well as the drivers (morphological features) of variation within and among species; and (ii) field observational and mesocosm studies were carried out to evaluate the role of the threatened fish B. meridionalis as modulator of the response of stream ecosystem structure and function to anthropogenic stressors, such as hydrologic alterations (e.g. resulting from the water diversion) and metal pollution. Our results showed that there exist a high intra-and interspecific variation in absolute critical swimming speed and metabolic traits in fish. Generally, swimming performance and aerobic metabolism scaled positively with body size. The study that compared the invasive mosquitofish (Gambusia holbrooki) with the native Spanish toothcarp (Aphanius iberus) revealed that mosquitofish can swim faster (i.e. higher critical swimming speed) and more efficiently than Spanish toothcarp, as it showed lower cost of transport at a comparable workload. Both sexes of mosquitofish showed a better hydrodynamic body shape, i.e. streamlined body and thiner caudal peduncle, both of which were positively correlated with swimming performance. The second study revealed that, after accounting for body size effects, critical swimming speed was independently affected by total length or maximal metabolic rate within certain fish species. At the interspecific level, variation in critical swimming speed was partly explained by the variation in the interrelated traits of maximal metabolic rate, and fineness and muscle ratios, when accounting for up to eight freshwater fish species. Field observational and mesocosm studies showed that the top-down control by grazers was largely responsible for the variation in structural responses of periphyton, such as biomass and nutrient content, and in functional responses, such as nutrient uptake rates. Generally, when grazer densities were higher the periphyton biomass (ash-free dry mass or chlorophyll-a) was lower, whereas the nitrogen content of periphyton increased (i.e. lower C:N). The higher phosphate uptake capacity by periphyton was likely due to a more rejuvenated and active periphyton community. In addition, the variation in macroinvertebrate and fish densities were directly related to the impacts of natural (floods) and anthropogenic stressors. In metal-polluted reaches, we found that direct negative effects of metals on grazers led to indirect positive effects on periphyton biomass. Our studies also provided evidence about the important functional role of the Mediterranean barbel (Barbus meridionalis) in streams because shifts in their densities can lead to large ecosystem changes. The absence of this predatory fish triggered trophic-cascade responses on periphyton biomass in low impacted streams, and led to modify phosphate uptake rates by periphyton through biotic interactions. On the contrary, this benthic fish markedly reduced periphyton biomass via bioturbation impacts, and the greatest consumption effects on macroinvertebrates were found in larvae of Chironomidae. Finally, it was discussed (i) the importance of fish swimming capabilities, metabolism and morphological traits in influencing patterns of species distributions in Mediterranean streams with hydrologic alterations; and (ii) the context dependency of stream community responses to anthropogenic stressors. A number of management actions and future research prospects in relation to our findings were also raised throughout this thesis.
... Taxonomic identification was basically carried out to the family level in accordance with Tachet et al. (2003). This family level has been often selected for practical biomonitoring of freshwater pollution and habitat degradation with benthic macroinvertebrates (Armitage et al., 1983;Rosenberg and Resh, 1993;Camargo et al., 2004;Ziglio et al., 2006;Alvial et al., 2012;Gartzia et al., 2015). After identification and counting, macroinvertebrate samples were dried in an oven at 60°C for 24 hours in order to estimate total biomass (dry-weight). ...
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Species richness is a fundamental measurement of community and regional diversity, and it underlies many ecological models and conservation strategies. In spite of its importance, ecologists have not always appreciated the effects of abundance and sampling effort on richness measures and comparisons. We survey a series of common pitfalls in quantifying and comparing taxon richness. These pitfalls can be largely avoided by using accumulation and rarefaction curves, which may be based on either individuals or samples. These taxon sampling curves contain the basic information for valid richness comparisons, including category–subcategory ratios (species-to-genus and species-to-individual ratios). Rarefaction methods – both sample-based and individual-based – allow for meaningful standardization and comparison of datasets. Standardizing data sets by area or sampling effort may produce very different results compared to standardizing by number of individuals collected, and it is not always clear which measure of diversity is more appropriate. Asymptotic richness estimators provide lower-bound estimates for taxon-rich groups such as tropical arthropods, in which observed richness rarely reaches an asymptote, despite intensive sampling. Recent examples of diversity studies of tropical trees, stream invertebrates, and herbaceous plants emphasize the importance of carefully quantifying species richness using taxon sampling curves.
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NOTE: This is not a book, contrary to what ResearchGate claims. This is a software application and User's Guide. The current version is Version 9. The citations here are incomplete, since each version has its own citations. EstimateS currently has more than 4000 citations in the peer-reviewed literature. For the full list, go to GoogleScholar: http://bit.ly/11YdUlg .
Rapid bioassessment protocols for use in streams and wadeable rivers: periphyton, benthic macroinvertebrates, and fish Developments in aquatic insect biomonitoring: a comparative analysis of recent approaches
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  • B D Snyder
  • J B Stribling
Barbour M.T., Gerritsen J., Snyder B.D. and Stribling J.B., 1999. Rapid bioassessment protocols for use in streams and wadeable rivers: periphyton, benthic macroinvertebrates, and fish, 2nd edition. EPA 841-B-99-002. US Environmental Protection Agency, Office of Water, Washington, DC, USA, 197 p. Bonada N., Prat N., Resh V.H. and Statzner B., 2006. Developments in aquatic insect biomonitoring: a comparative analysis of recent approaches. Annu. Rev. Entomol., 51, 495–523.
Development of rapid bioassessment ap-proaches using benthic macroinvertebrates for Thai streams Estimating processing time of stream benthic samples
  • B Gartzia
  • De
B. Gartzia De Bikuña et al.: Knowl. Manag. Aquat. Ecosyst. (2015) 416, 08 Boonsoong B., Sangpradub N. and Barbour M.T., 2009. Development of rapid bioassessment ap-proaches using benthic macroinvertebrates for Thai streams. Environ. Monit. Assess., 155, 129−147. Ciborowski J.J.H., 1991. Estimating processing time of stream benthic samples. Hydrobiologia, 222, 101–107.
Invertébrés d'eau douce: systéma-tique, biologie et écologie, CNRS : Paris, 587 p Linking ecosystem services, rehabilitation, and river hydrogeomorphol-ogy
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