Tolerance of benthic macroinvertebrates to organic enrichment in highland streams of northeastern Rio Grande do Sul, Brazil

Abstract

AIM: the aim of this study was to determine the ecological valence of benthic macroinvertebrates at different pollution levels in highland rivers and streams of Rio Grande do Sul; METHODS: the dataset proceeds from samplings performed between 2002-2011 in 35 lotic ecosystems. The Chemical Index was used to determine pollution levels. Indices of richness and Shannon diversity were applied to characterize the structure of benthic communities. The descriptors used to determine taxa's ecological valence were selected according to Coefficient of Variation and regression analyses. Groups of tolerance were identified using Interquartile range and cluster analysis; RESULTS: Conductivity and Chemical Index were the descriptors best related with diversity of benthic macroinvertebrate community. These metrics were used to determine the tolerance range of 38 taxa. Interquartile range and cluster analysis revealed three groups of taxa, according to their occurrence in different levels of pollution: taxa with narrow amplitudes, present at sites with very low or very high load of organic enrichment; taxa with moderate amplitude, found until moderately polluted sites; and taxa with occurrence in widespread environmental conditions. The results, when compared to other studies in Brazil, showed differences in some taxa's tolerance. This observation indicates the need to assess the bioindication potential of these taxa in genus and species level; CONCLUSION: the present study contributes to increase knowledge about the bioindicator potential of benthic macroinvertebrates. Therefore, the study supports an advanced biomonitoring of ecological quality in mountain streams of southern Brazil.

Rehabilitation scenarios for reservoirs: Predicting their effect on invertebrate communities through machine learning

“…Here, we used this scale for comparative purposes only, as the index was developed for rivers and temperate systems, where diversity is naturally higher. Finally, we selected three of the most abundant of sensitive taxa of different orders to analyze the potential changes in their spatial distribution resulting from rehabilitation measures: the Ephemeroptera Caenidae, the Trichoptera Polycentropodidae and the Diptera Chironomidae Zavreliella (Butakka, Ragonha, & Takeda, 2014; Costa, Alves, Weber, Pestana, & Capelo‐Neto, 2017; Mazzoni, Lanzer, & Schafer, 2014).…”

Aproximación preliminar a un índice multimétrico de macroinvertebrados (IMARBO) para evaluar el estado ecológico de ríos de las cuencas alta y media del río Chicamocha en Boyacá, Colombia

“…Gestión y Ambiente 23(1). DOI: https://doi.org/10.15446/ga.v23n1.83792 9 muestras de 1 L en recipientes plásticos, las cuales se refrigeraron a 4 ºC y se llevaron a un laboratorio certificado antes de 8 horas, en el que se analizaron solidos disueltos totales (mg L -1 ), fosfatos (mg L -1 P-PO 4 -3 ), nitratos (mg L -1 NO 3 ), demanda biológica de oxígeno (DBO 5 , mg Ante la dificultad de identificar todos los organismos a género o especie, todas las métricas de los taxones se determinaron para el nivel de familia, el cual se ha utilizado ampliamente en este tipo propuestas de bioindicación debido a su eficiencia, bajos costos, menor esfuerzo y aportes relevantes en la indicación biológica (Moya et al, 2011;Mazzoni et al, 2014;Ríos-Touma et al, 2014).…”

Differential environmental impacts on small and medium size rivers from center of São Paulo State, Brazil, and regional management perspectives

“…Ternus et al (2011) observed significant conductivity increase in river courses passing through urban areas with no marginal vegetation. Conductivity also provided to be useful to differentiate ecological conditions and correlation with biota (Braun et al, 2014;Cunha et al, 2014;Mazzoni et al, 2014;Suriano et al, 2011).…”

“…Regionally these rivers indicate a relatively good conservation status. Riparian forests and whole watershed land cover are significantly correlated with the water quality metrics, particularly nutrient concentrations, and the agricultural and/or urban lands are the most important predictors of water quality degradation (Dodds and Oakes, 2008;Kuhlmann et al, 2014;Mazzoni et al, 2014). Fonseca et al (2014) consider that agriculture and planted pasture have caused major impacts on river watersheds of Cerrado Domain, such as water uses, conservation and restoration of wetlands and reduced applications to match crop needs (Allan, 2004;Carpenter et al, 1998;Dodds and Oakes, 2008;Hoffmann et al, 2009;Fore et al, 2014;Kuhlmann et al, 2014;Liu et al, 2014).…”