Benthic community ecology for Algerian river Seybouse / Ecologia da comunidade bêntica para o rio Seybouse da Argélia

Abstract The Seybouse is the second largest river basin in Algeria, hosting an important biodiversity and providing various ecosystem services. This watershed is highly influenced by agricultural and industrial activities, which threaten its biodiversity and ecosystem integrity. The use of benthic macroinvertebrates as biological indicators has a long tradition in developed countries and integrated into all assessments of the ecological quality of river systems. However, the macroinvertebrates of many North African regions are still not well studied, including those of the Seybouse river. The aim of this study is to assess the inventory and ecological role of benthic macroinvertebrates in inland waters of the Seybouse River and determine the impact of pollution on their spatial distributions. We sampled the benthic macrofauna of Wadi Seybouse and its affluents using regular surveys in three sites, of which one was in the upper Seybouse Bouhamdane in Medjez Amar and two in the middle Seybouse. Between December 2019 and May 2020, 10 physico-chemical parameters (pH, EC, OD, water speed, NO3, Salinity, NO2, MES, turbidity, depth) were measured in order to establish a health state diagnosis of these aquatic ecosystems. The complementary biological approach by the analysis of populations of macroinvertebrates identified 7482 individuals and 40 taxa divided into five classes: Crustaceans which were the most dominant, insects with the main orders (Ephemeroptera, Diptera, Trichoptera, Heteroptera and Odonata), Molluscs, Nematodes and Annelids. The physico-chemical analyzes and the application of the organic pollution indices indicated a strong to excessive pollution for all sites, especially in Seybouse upstream

Resumo O Seybouse é um rio no nordeste da Argélia, é o segundo maior rio, tem uma área de captação de cerca de 6.500 km2 que acolhe cerca de 1,5 milhões de habitantes. Importantes atividades agrícolas e industriais são desenvolvidas nesta bacia hidrográfica. O uso de macroinvertebrados bentônicos como indicadores biológicos tem uma longa tradição em países desenvolvidos e está integrado em todas as avaliações da qualidade ecológica dos sistemas fluviais. O objetivo deste estudo foi revisar o inventário e o papel ecológico dos macroinvertebrados bentônicos nas águas interiores do rio Seybouse e determinar o impacto da poluição em suas distribuições. Resultados semelhantes foram relatados para outros países e rios argelinos. Este estudo enfoca a macrofauna bentônica de Wadi Seybouse e seus afluentes. Foram prospectados 03 locais, um no alto Seybousse Bouhamdane em Medjez Amar e dois no meio Seybousse Salah Salah Salah e Oued Zimba. Entre dezembro de 2019 e maio de 2020, dez parâmetros físico-químicos (pH, CE, DO, velocidade da água, NO3, Salinidade, NO2, MES, turbidez, deth) foram medidos para estabelecer um diagnóstico do estado de saúde desses ecossistemas aquáticos. A abordagem biológica complementar pela análise de populações de macroinvertebrados identificou 7.482 indivíduos e 40 táxons divididos em cinco classes: Crustáceos que são os mais dominantes, Insetos com as ordens principais (Ephemeroptera, Diptera, Trichoptera, Heteroptera e Odonata), Moluscos, Nematóides e Anelídeos. As análises físico-químicas e a aplicação dos índices de poluição orgânica, indicaram uma poluição forte a excessiva para todos os locais especialmente Salah Salah Salah.

Benthic community ecology for Algerian river Seybouse

Abstract The Seybouse is the second largest river basin in Algeria, hosting an important biodiversity and providing various ecosystem services. This watershed is highly influenced by agricultural and industrial activities, which threaten its biodiversity and ecosystem integrity. The use of benthic macroinvertebrates as biological indicators has a long tradition in developed countries and integrated into all assessments of the ecological quality of river systems. However, the macroinvertebrates of many North African regions are still not well studied, including those of the Seybouse river. The aim of this study is to assess the inventory and ecological role of benthic macroinvertebrates in inland waters of the Seybouse River and determine the impact of pollution on their spatial distributions. We sampled the benthic macrofauna of Wadi Seybouse and its affluents using regular surveys in three sites, of which one was in the upper Seybouse Bouhamdane in Medjez Amar and two in the middle Seybouse. Between December 2019 and May 2020, 10 physico-chemical parameters (pH, EC, OD, water speed, NO3, Salinity, NO2, MES, turbidity, depth) were measured in order to establish a health state diagnosis of these aquatic ecosystems. The complementary biological approach by the analysis of populations of macroinvertebrates identified 7482 individuals and 40 taxa divided into five classes: Crustaceans which were the most dominant, insects with the main orders (Ephemeroptera, Diptera, Trichoptera, Heteroptera and Odonata), Molluscs, Nematodes and Annelids. The physico-chemical analyzes and the application of the organic pollution indices indicated a strong to excessive pollution for all sites, especially in Seybouse upstream

Resumo O Seybouse é um rio no nordeste da Argélia, é o segundo maior rio, tem uma área de captação de cerca de 6.500 km2 que acolhe cerca de 1,5 milhões de habitantes. Importantes atividades agrícolas e industriais são desenvolvidas nesta bacia hidrográfica. O uso de macroinvertebrados bentônicos como indicadores biológicos tem uma longa tradição em países desenvolvidos e está integrado em todas as avaliações da qualidade ecológica dos sistemas fluviais. O objetivo deste estudo foi revisar o inventário e o papel ecológico dos macroinvertebrados bentônicos nas águas interiores do rio Seybouse e determinar o impacto da poluição em suas distribuições. Resultados semelhantes foram relatados para outros países e rios argelinos. Este estudo enfoca a macrofauna bentônica de Wadi Seybouse e seus afluentes. Foram prospectados 03 locais, um no alto Seybousse Bouhamdane em Medjez Amar e dois no meio Seybousse Salah Salah Salah e Oued Zimba. Entre dezembro de 2019 e maio de 2020, dez parâmetros físico-químicos (pH, CE, DO, velocidade da água, NO3, Salinidade, NO2, MES, turbidez, deth) foram medidos para estabelecer um diagnóstico do estado de saúde desses ecossistemas aquáticos. A abordagem biológica complementar pela análise de populações de macroinvertebrados identificou 7.482 indivíduos e 40 táxons divididos em cinco classes: Crustáceos que são os mais dominantes, Insetos com as ordens principais (Ephemeroptera, Diptera, Trichoptera, Heteroptera e Odonata), Moluscos, Nematóides e Anelídeos. As análises físico-químicas e a aplicação dos índices de poluição orgânica, indicaram uma poluição forte a excessiva para todos os locais especialmente Salah Salah Salah.

Composición de los macroinvertebrados según la calidad del agua en turberas de altura, Costa Rica / Composition of macroinvertebrates according to water quality in high altitude peatbogs, Costa Rica

Resumen Introducción: En Costa Rica, las turberas de altura se localizan en la Cordillera de Talamanca de 2 400 a 3 200 m. Se forman a partir de depósitos de materia orgánica en descomposición, con oxígeno reducido y baja disponibilidad de nutrientes. Objetivo: Evaluar la variación en la composición de macroinvertebrados acuáticos según parámetros fisicoquímicos de calidad del agua superficial en turberas de altura, Costa Rica. Métodos: Se colocaron 32 sustratos artificiales en las turberas para ser colonizados por macroinvertebrados. Se realizaron evaluaciones fisicoquímicas mensuales del agua superficial en ocho turberas con visitas mensuales durante la estación lluviosa. Se utilizaron los índices ICA-NSF y BMWP-CR para evaluar la calidad del agua. Resultados: Se registraron un total de diez familias correspondientes a siete géneros. Las familias más representativas fueron Chironomidae y Limnephilidae. La calidad del agua se clasificó según el ICA-NSF como de "calidad media" y como de "calidad regular a mala" según el BMWP-CR. Conclusiones: Las turberas de altura son ecosistemas poco estudiados, esta investigación evidencia la necesidad de diseñar metodologías e índices que evalúen la fauna acuática. Las turberas son diferentes entre sí, y las familias de macroinvertebrados encontrados son tolerantes a las características fisicoquímicas del agua. Es necesario realizar estudios periódicos que evalúen la calidad del agua y su relación con los macroinvertebrados acuáticos para entender la dinámica de las turberas, generar conocimiento e incrementar su protección.

Abstract Introduction: In Costa Rica, high peatbogs are located in the Cordillera de Talamanca from 2 400 to 3 200 m. They are formed from deposits of decomposing organic matter, with reduced oxygen and low nutrient availability. Objective: To evaluate the variation in the composition of aquatic macroinvertebrates according to physicochemical parameters of superficial water quality in high altitude peatbogs, Costa Rica. Methods: 32 artificial substrates were placed in the peatbogs to be colonized by macroinvertebrates. Monthly physicochemical evaluations of surface water were performed in eight peatbogs with monthly visits during the rainy season. The ICA-NSF and BMWP-CR indexes were used to evaluate the water quality. Results: A total of ten families corresponding to seven genera were recorded. The most representative family was Chironomidae and Limnephilidae. Water quality was classified according to the ICA-NSF as "medium quality" and as "regular to poor quality" according to BMWP-CR. Conclusions: The high peatbogs are poorly studied ecosystems; this research shows the need to design methodologies and indices to evaluate the aquatic fauna. The peatbogs are different from each other, and the families of macroinvertebrates found are tolerant to the physicochemical characteristics of the water. Periodic studies that evaluate water quality and its relationship with aquatic macroinvertebrates are necessary to understand the dynamics of peatlands, generate knowledge and increase their protection.

Variabilidad de comunidades de macroinvertebrados acuáticos en charcas temporales del norte de Colombia

Introducción: Las charcas temporales son ecosistemas acuáticos variables en su estructura física y biótica, efímeros en el paisaje e importantes en el flujo de materia y energía. Los macroinvertebrados acuáticos constituyen el grupo más abundante y diverso en estos ecosistemas y requieren mayor estudio, particularmente en los trópicos. Objetivo: Evaluar la diversidad alfa y beta de las comunidades de macroinvertebrados acuáticos de seis charcas temporales durante dos épocas climáticas en el norte de Colombia. Métodos: En Magdalena, Colombia, hicimos seis arrastres aleatorios con redes manuales en la zona litoral, y seis arrastres en zigzag con redes tipo D en la zona lacustre; recolectamos macrofauna en tres lances con una draga Ekman; y muestreamos cada charca durante la alta precipitación (noviembre, 2020) y la baja precipitación (febrero, 2021). Resultados: Identificamos 3 358 individuos (13 órdenes, 39 familias y 68 géneros). La mayor abundancia y diversidad (N= 485, 0D= 32) durante la época de lluvia se presentó en Los Campanos, mientras que la charca Villa Leidy tuvo el mayor número de taxones comunes (18) y dominantes (14). En la época de sequía, la charca Los Trillizos presentó la mayor abundancia (533) y diversidad (43); mientras que Villa Leidy y El Miquito el mayor número de taxones dominantes (16). Las charcas tienen composiciones particulares (sin agrupamientos espaciales o temporales); el recambio de taxones es alto, y la correspondencia canónica se agrupa por temporada. Conclusiones: la composición de las comunidades de macroinvertebrados acuáticos de las charcas temporales son muy diversas, presentando alto recambio tanto espacial como temporal, reflejando altos valores de remplazo de taxones entre épocas climáticas. La zona litoral mantuvo una composición similar durante las dos temporadas.

Introduction: Temporary ponds are variable aquatic ecosystems in their physical and biotic structure, ephemeral in the landscape and important in the flow of matter and energy. Aquatic macroinvertebrates constitute the most abundant and diverse group in these ecosystems and need further study, particularly in the tropics. Objective: To evaluate the alpha and beta diversity of the aquatic macroinvertebrate communities of six temporary pools during two climatic seasons in Northern Colombia. Methods: In Magdalena, Colombia, we did six random trawls with hand nets in the coastal zone, and six zig zag trawls with D nets in the lacustrine zone; we collected macrofauna in three random hauls with an Ekman dredge; and sampled each pond in high rainfall (November 2020) and low rainfall (February 2021). Results: We identified 3 358 individuals (13 orders, 39 families and 68 genera). The highest rainy season abundance and diversity (N= 485, 0D= 32) were in Los Campanos, while Villa Leidy Pond had the highest number of common (18) and dominant (14) taxa. During the dry season, Los Trillizos Pond had the highest abundance (533) and diversity (43); while Villa Leidy and El Miquito had the largest number of dominant taxa (16). The pools have a particular composition (no spatial or temporal grouping); taxa turnover is high, and the canonical correspondence clustered by season. Conclusions: The aquatic macroinvertebrate communities of the temporary ponds are diverse and have high turnover in space and time, reflecting high replacement of taxa between climatic periods. The littoral zone had a similar composition in the two seasons.

Ecological relevance of non-perennial rivers for the conservation of terrestrial and aquatic communities.

River conservation efforts traditionally focus on perennial watercourses (i.e., those that do not dry) and their associated aquatic biodiversity. However, most of the global river network is not perennial and thus supports both aquatic and terrestrial biodiversity. We assessed the conservation value of nonperennial rivers and streams (NPRS) in one of Europe's driest regions based on aquatic (macroinvertebrates, diatoms) and terrestrial (riparian plants, birds, and carabid beetles) community data. We mapped the distribution of taxa at 90 locations and across wide environmental gradients. Using the systematic planning tool Marxan, we identified priority conservation sites under 2 scenarios: aquatic taxa alone or aquatic and terrestrial taxa together. We explored how environmental factors (runoff, flow intermittence, elevation, salinity, anthropogenic impact) influenced Marxan's site selection frequency. The NPRS were selected more frequently (over 13% on average) than perennial rivers when both aquatic and terrestrial taxa were considered, suggesting that NPRS have a high conservation value at the catchment scale. We detected an underrepresentation of terrestrial taxa (8.4-10.6% terrestrial vs. 0.5-1.1% aquatic taxa were unrepresented in most Marxan solutions) when priority sites were identified based exclusively on aquatic biodiversity, which points to a low surrogacy value of aquatic taxa for terrestrial taxa. Runoff explained site selection when focusing on aquatic taxa (all best-fitting models included runoff, r2  = 0.26-0.27), whereas elevation, salinity, and flow intermittence were more important when considering both groups. In both cases, site selection frequency declined as anthropogenic impact increased. Our results highlight the need to integrate terrestrial and aquatic communities when identifying priority areas for conservation in catchments with NPRS. This is key to overcoming drawbacks of traditional assessments based only on aquatic taxa and to ensure the conservation of NPRS, especially as NPRS become more prevalent worldwide due to climate change and increasing water demands.

Los esfuerzos de conservación fluvial se enfocan tradicionalmente en los cauces permanentes (aquellos que no se secan) y la biodiversidad acuática asociada. Sin embargo, la mayor parte de la red hidrográfica mundial no es permanente, por lo que sustenta biodiversidad tanto acuática como terrestre. Evaluamos el valor de conservación de los ríos y arroyos no permanentes (RANP) en una de las regiones más secas de Europa con datos de comunidades acuáticas (macroinvertebrados, diatomeas) y terrestres (escarabajos carábidos). Mapeamos la distribución de los taxones en 90 localidades que cubren gradientes ambientales amplios. Con la herramienta de planificación sistemática Marxan identificamos los sitios prioritarios de conservación bajo dos escenarios: considerando sólo los taxones acuáticos o los taxones acuáticos y terrestres juntos. Exploramos cómo los factores ambientales (escorrentía, intermitencia del caudal, altitud, salinidad, impacto antropogénico) influyeron sobre la frecuencia de selección de sitio de Marxan. Los RANP fueron seleccionados con mayor frecuencia (más del 13% en promedio) que los ríos permanentes cuando consideramos los taxones acuáticos y terrestres, lo que sugiere que los RANP tienen un valor elevado de conservación a escala de cuenca. Detectamos que los taxones terrestres estaban infrarrepresentados (8.4-10.6% taxones terrestres vs. 0.5-1.1% acuáticos no tuvieron representación en la mayoría de las soluciones de Marxan) cuando los sitios prioritarios para la conservación se identificaban exclusivamente con la biodiversidad acuática, lo que indica que los taxones acuáticos tienen un reducido valor indicador para los taxones terrestres. La escorrentía determinó la selección de sitios cuando se basó en los taxones acuáticos (los mejores modelos incluyeron la escorrentía, r2 = 0.26-0.27), mientras que la altitud, la salinidad y la intermitencia del caudal fueron más importantes cuando se consideraron ambos grupos. En ambos casos, la frecuencia de selección disminuyó conforme se incrementó el impacto antropogénico. Nuestros resultados resaltan la necesidad de integrar las comunidades terrestres y acuáticas a la identificación de las áreas prioritarias para la conservación de la biodiversidad en cuencas con RANP. Lo anterior es importante para superar las evaluaciones tradicionales basadas solamente en los taxones acuáticos y para garantizar la conservación de los RANP, especialmente ahora que estos son cada vez más frecuentes a nivel mundial debido al cambio climático y a la creciente demanda de agua.

Community structure of benthic invertebrates in the Allipén River basin, North Patagonia, Araucania region (38º S, Chile) / Estrutura da comunidade de invertebrados bentônicos na bacia do rio Allipén, Patagônia Norte, Região da Araucanía (38º S, Chile)

One of the biological indicators most used to determine the health of a fluvial ecosystem are the benthic macroinvertebrates. The presence of recurrent species in a wide gradient of latitudes, dominates the biogeographic pattern of the benthic macroinvertebrates in Chilean fresh waters, nevertheless the knowledge on the communitarian ecology of these in the Chilean rivers continues to be scarce. Null models became a powerful statistical tool for describing the ecological mechanisms that drive the structure of an ecological community and the underlying patterns of diversity. The objective of this study was to determine the community structure of benthic invertebrates in the Allipén River by describing their composition, richness and abundance of species through richness models and null models based on presence/absence. The results reveal a high family richness and low diversity, three phyla, five classes, 11 orders and 28 families were identified in the study area during the four seasons of the year. The Arthropoda phylum was the most representative in abundance and richness. Regarding to richness, Trichoptera (7 families) and Diptera (6 families) followed by Ephemeroptera (3 families) were the orders that showed the greatest diversity of families, however, a low diversity with a H'≤ 1.5 nit was registered in the study area. We demonstrated through the null models, the randomization in the species associations corresponding to the three analyzed sites. The information provided here contributes to the understanding of the ecological patterns of the invertebrate communities in the Allipén River, establishing the basis for more complex ecological studies.

Um dos indicadores biológicos mais utilizados para determinar a saúde de um ecossistema fluvial são os macroinvertebrados bentônicos. A presença de espécies recorrentes em um amplo gradiente de latitudes domina o padrão biogeográfico dos macroinvertebrados bentônicos nas águas doces do Chile; no entanto, o conhecimento sobre a ecologia comunitária destes nos rios chilenos continua escasso. Os modelos nulos se tornaram uma poderosa ferramenta estatística para descrever os mecanismos ecológicos que orientam a estrutura de uma comunidade ecológica e os padrões subjacentes da diversidade. O objetivo deste estudo foi determinar a estrutura da comunidade de invertebrados bentônicos no rio Allipén, descrevendo sua composição, riqueza e abundância de espécies através de modelos de riqueza e modelos nulos baseados na presença / ausência. Os resultados revelam alta riqueza de espécies e baixa diversidade, sendo identificados três filos, cinco classes, 11 ordens e 28 famílias na área de estudo durante as quatro estações do ano. O filo de Arthropoda foi o mais representativo em abundância e riqueza. Em relação à riqueza, Trichoptera (7) e Diptera (6) seguidos por Ephemeroptera (3) foram as ordens que mostraram a maior diversidade de famílias, no entanto, uma baixa diversidade com H'≤ 1,5 nit foi registrada na área de estudo. Demonstramos através dos modelos nulos, a randomização nas associações de espécies correspondentes aos três locais analisados. As informações aqui fornecidas contribuem para a compreensão dos padrões ecológicos das comunidades de invertebrados no rio Allipén, estabelecendo a base para estudos ecológicos mais complexos.

Community structure of benthic invertebrates in the Allipén River basin, North Patagonia, Araucania region (38º S, Chile) / Estrutura da comunidade de invertebrados bentônicos na bacia do rio Allipén, Patagônia Norte, Região da Araucanía (38º S, Chile)

One of the biological indicators most used to determine the health of a fluvial ecosystem are the benthic macroinvertebrates. The presence of recurrent species in a wide gradient of latitudes, dominates the biogeographic pattern of the benthic macroinvertebrates in Chilean fresh waters, nevertheless the knowledge on the communitarian ecology of these in the Chilean rivers continues to be scarce. Null models became a powerful statistical tool for describing the ecological mechanisms that drive the structure of an ecological community and the underlying patterns of diversity. The objective of this study was to determine the community structure of benthic invertebrates in the Allipén River by describing their composition, richness and abundance of species through richness models and null models based on presence/absence. The results reveal a high family richness and low diversity, three phyla, five classes, 11 orders and 28 families were identified in the study area during the four seasons of the year. The Arthropoda phylum was the most representative in abundance and richness. Regarding to richness, Trichoptera (7 families) and Diptera (6 families) followed by Ephemeroptera (3 families) were the orders that showed the greatest diversity of families, however, a low diversity with a H'≤ 1.5 nit was registered in the study area. We demonstrated through the null models, the randomization in the species associations corresponding to the three analyzed sites. The information provided here contributes to the understanding of the ecological patterns of the invertebrate communities in the Allipén River, establishing the basis for more complex ecological studies.

Um dos indicadores biológicos mais utilizados para determinar a saúde de um ecossistema fluvial são os macroinvertebrados bentônicos. A presença de espécies recorrentes em um amplo gradiente de latitudes domina o padrão biogeográfico dos macroinvertebrados bentônicos nas águas doces do Chile; no entanto, o conhecimento sobre a ecologia comunitária destes nos rios chilenos continua escasso. Os modelos nulos se tornaram uma poderosa ferramenta estatística para descrever os mecanismos ecológicos que orientam a estrutura de uma comunidade ecológica e os padrões subjacentes da diversidade. O objetivo deste estudo foi determinar a estrutura da comunidade de invertebrados bentônicos no rio Allipén, descrevendo sua composição, riqueza e abundância de espécies através de modelos de riqueza e modelos nulos baseados na presença / ausência. Os resultados revelam alta riqueza de espécies e baixa diversidade, sendo identificados três filos, cinco classes, 11 ordens e 28 famílias na área de estudo durante as quatro estações do ano. O filo de Arthropoda foi o mais representativo em abundância e riqueza. Em relação à riqueza, Trichoptera (7) e Diptera (6) seguidos por Ephemeroptera (3) foram as ordens que mostraram a maior diversidade de famílias, no entanto, uma baixa diversidade com H'≤ 1,5 nit foi registrada na área de estudo. Demonstramos através dos modelos nulos, a randomização nas associações de espécies correspondentes aos três locais analisados. As informações aqui fornecidas contribuem para a compreensão dos padrões ecológicos das comunidades de invertebrados no rio Allipén, estabelecendo a base para estudos ecológicos mais complexos.

Community structure of benthic invertebrates in the Allipén River basin, North Patagonia, Araucania region (38º S, Chile)

Abstract One of the biological indicators most used to determine the health of a fluvial ecosystem are the benthic macroinvertebrates. The presence of recurrent species in a wide gradient of latitudes, dominates the biogeographic pattern of the benthic macroinvertebrates in Chilean fresh waters, nevertheless the knowledge on the communitarian ecology of these in the Chilean rivers continues to be scarce. Null models became a powerful statistical tool for describing the ecological mechanisms that drive the structure of an ecological community and the underlying patterns of diversity. The objective of this study was to determine the community structure of benthic invertebrates in the Allipén River by describing their composition, richness and abundance of species through richness models and null models based on presence/absence. The results reveal a high family richness and low diversity, three phyla, five classes, 11 orders and 28 families were identified in the study area during the four seasons of the year. The Arthropoda phylum was the most representative in abundance and richness. Regarding to richness, Trichoptera (7 families) and Diptera (6 families) followed by Ephemeroptera (3 families) were the orders that showed the greatest diversity of families, however, a low diversity with a H 1.5 nit was registered in the study area. We demonstrated through the null models, the randomization in the species associations corresponding to the three analyzed sites. The information provided here contributes to the understanding of the ecological patterns of the invertebrate communities in the Allipén River, establishing the basis for more complex ecological studies.

Resumo Um dos indicadores biológicos mais utilizados para determinar a saúde de um ecossistema fluvial são os macroinvertebrados bentônicos. A presença de espécies recorrentes em um amplo gradiente de latitudes domina o padrão biogeográfico dos macroinvertebrados bentônicos nas águas doces do Chile; no entanto, o conhecimento sobre a ecologia comunitária destes nos rios chilenos continua escasso. Os modelos nulos se tornaram uma poderosa ferramenta estatística para descrever os mecanismos ecológicos que orientam a estrutura de uma comunidade ecológica e os padrões subjacentes da diversidade. O objetivo deste estudo foi determinar a estrutura da comunidade de invertebrados bentônicos no rio Allipén, descrevendo sua composição, riqueza e abundância de espécies através de modelos de riqueza e modelos nulos baseados na presença / ausência. Os resultados revelam alta riqueza de espécies e baixa diversidade, sendo identificados três filos, cinco classes, 11 ordens e 28 famílias na área de estudo durante as quatro estações do ano. O filo de Arthropoda foi o mais representativo em abundância e riqueza. Em relação à riqueza, Trichoptera (7) e Diptera (6) seguidos por Ephemeroptera (3) foram as ordens que mostraram a maior diversidade de famílias, no entanto, uma baixa diversidade com H 1,5 nit foi registrada na área de estudo. Demonstramos através dos modelos nulos, a randomização nas associações de espécies correspondentes aos três locais analisados. As informações aqui fornecidas contribuem para a compreensão dos padrões ecológicos das comunidades de invertebrados no rio Allipén, estabelecendo a base para estudos ecológicos mais complexos.

Insectos acuáticos asociados a arroyos de la Serranía de La Macuira - La Guajira, Colombia / Aquatic insects associated with streams of the Serranía de la Macuira - La Guajira, Colombia

RESUMEN Los insectos acuáticos tienen gran importancia en los ecosistemas fluviales, debido a su alta abundancia y diversidad e indicadores de calidad de agua. En este trabajo, se caracterizaron las comunidades de insectos acuáticos en La Macuira, norte de La Guajira colombiana. Se seleccionaron cinco arroyos intermitentes, como sitios de muestreo: Mekijanoü, Chaamaalüü, Kanewerü, Mmalaüü y Kajashiwoü. Para la colecta de los organismos, se empleó una red Surber, durante cinco minutos. Además, se tomaron muestras de hojarasca (cerca de 500g) del fondo del río. Las muestras recolectadas en los diferentes microhábitats en cada sitio, se integraron para conformar una muestra compuesta y posterior análisis de la diversidad; además, se calculó el índice de calidad de agua BMWP/Col en cada uno de los arroyos, para conocer la calidad de sus aguas. Se colectaron en total 545 individuos, distribuidos en 25 géneros, 19 familias y 7 órdenes. Se registran, por primera vez, para la Serranía de la Macuira, los géneros Heterelmis, Corydalus, Rhagovelia, Mayobaetis, Tholymis y Mecistogaster. El arroyo Mekijanoü presentó la mayor abundancia (411 individuos) y riqueza de géneros, en la que predominó la presencia de Heterelmis y Kajashiwoü, la menor abundancia (20 individuos), fluctuada por la formación de pozos y la poca conectividad. Los valores del índice BMWP/Col oscilaron entre 41 y 87, lo cual, indica que cuatro arroyos presentaron una moderada contaminación y uno se encontraba ligeramente contaminado.

ABSTRACT Aquatic insects are high importance in aquatic ecosystems due to their high abundance and diversity and water quality indicators. In this work, assemblages of aquatic insects were studied in La Macuira, northern La Guajira, Colombia. Five intermittent streams were selected as sampling sites such as Mekijanoü, Chaamaalüü, Kanewerü, Mmalaüü and Kajashiwoü. Surber net was used for collecting of organisms for five minutes; also, samples of leaf litter were taken manually of the streambed. The samples collected were integrated to form a sample composed on each site, and then analyze this diversity; also, the water quality index BMWP/Col was estimated for each site. A total of 545 individuals were collected, grouped in 25 genus, 19 families and 7 orders. The genus Heterelmis, Corydalus, Rhagovelia and Mayobaetis, Tholymis and Mecistogaster are recorded for the first time for the Serranía de la Macuira. The Mekijanoü stream presented the high abundance (411 individuals) and genera, in which Heterelmis predominated. In contrast, Kajashiwoü presented the lowest abundance (20 individuals) fluctuated by the formation of wells and poor connectivity between them. The BMWP/Col index whose ranged from 41 to 87, indicating that four streams showed a moderate contamination and one was slightly contaminated.

Roles tróficos de la comunidad de macroinvertebrados y calidad ecológica del río Muincha / Tophic roles of community of macroinvertebrates and ecological quality of the Muincha river

Introducción: El suelo en áreas rurales del municipio de Turmequé-Boyacá-Colombia está destinado para actividades agrícolas y pecuarias en un 89%, lo cual tiene influencia en el estado ecológico del río Muincha. Objetivo: establecer los roles tróficos de la comunidad de macroinvertebrados y evaluar la calidad ecológica del río Muincha. Materiales y Métodos: Se realizaron 5 muestreos de la comunidad de macroinvertebrados durante los meses de mayo, junio, agosto, septiembre y noviembre de 2005. Las muestras de la comunidad de macroinvertebrados fueron colectadas en cuatro estaciones, tomando dos puntos cada una en un tramo entre 2431 y 2820 msnm del Río Muincha en Turmequé. Para evaluar la calidad ecológica se usaron los índices BMWP/Col (análisis biológico), EPT (análisis biológico) e INSF (análisis fisicoquímico), y se establecieron los roles tróficos de la comunidad de macroinvertebrados. Resultados: según BMWP/Col e INSF el río presenta agua de calidad aceptable (aguas ligeramente contaminadas) o de regular calidad. El ecosistema se encuentra alterado como consecuencia de la acción antrópica (ganadería y agricultura), la estación III presentó mayor afectación, y la Estación IV menor afectación. La contaminación encontrada posiblemente se deba al mal uso del suelo, evidenciado con la presencia constante y considerable de Colectores, Recolectores, Detritívoros (Ordenes Diptera, Seriata, Haplotaxida y Arthicobdellida), por la presencia de amonio y los altos valores de nitrato y fosfato. Conclusión: Se identificó una clara relación entre la diversidad de macroinvertebrados, los roles tróficos de los macroinvertebrados, la calidad del agua y los usos del suelo (calidad ambiental).

Introduction: The soil in rural areas from the municipality of Turmequé-Boyacá-Colombia is destined to activities agricultural and livestock, it represents the 89%, which have influence in the ecological state of the Muincha river. Objective: to establish trophic roles of the macroinvertebrates community and to evaluate the ecological quality of the Muincha river. Materials and Methods: in 2015 five samplings were performed in the month of may, June, August, September and November. The macroinvertebrates community samples were collected in four stations, taking two points in every one in a section of the 2431 to 2820 slom, in the Muincha river (Turmequé). To evaluate the ecological quality, it´s used the indexes BMWP/Col (biological analyses), EPT (biological analyses) and INSF (physicochemical analyses), and itself established trophic roles of the macroinvertebrates community. Results: agree BMWP/Col and INSF the river present water of acceptable quality (contaminated slightly water) or regular quality. The ecosystem itself found altered as consequence of the anthropic action (livestock and agriculture), the station III showing more affectation, and the station IV less affectation. Therefore, it´s identified clear relation between the diversity of macroinvertebrates, the quality of water and the use of the soil. The contamination found is possibly due to the misuse of the soil, evidenced by the constant and considerable presence of Collectors - Collectors Collectors ­ Gatherers - Detritivores (Ordenes Diptera, Seriata, Haplotaxida y Arthicobdellida), by the presence of Ammonium and the high values of nitrate and phosphate. Conclusion: Therefore, it´s identify a clear relation between the diversity of macroinvertebrates, trophic roles of the macroinvertebrates, quality of water and the uses of soil (environmental quality).

Evaluación de la calidad del agua de un río tropical usando índices bióticos, fisicoquímicos y de diversidad / Water quality assessment of a tropical stream using biotic, physicochemical and diversity indices

Introducción: Los ríos andinos en Colombia están fuertemente influenciados por diferentes actividades antrópicas. Los macroinvertebrados han sido utilizados para evaluar la calidad del agua en estos ecosistemas. Objetivo: Este estudio analizó el comportamiento de diferentes índices basados en macroinvertebrados para evaluar la calidad del agua del tramo medio-bajo del río Jordán en Jamundí (Colombia). Materiales y métodos: Se ubicaron tres estaciones de muestreo: E1 (1173 m.s.n.m.), E2 (1069 m.s.n.m.) y E3 (1019 m.s.n.m.). Se colectaron individuos en grava, bolos y macrófitas (n=15) y se midieron las concentraciones de variables fisicoquímicas y microbiológicas (n=15). Se evaluaron los índices de calidad de agua ICA-NSF y bióticos (BMWP/Univalle, ASPT y EPT) y los índices de Shannon-Weaver, Margalef y Simpson. Se realizó una correlación de Spearman entre las matrices de similitud biótica y ambiental. Resultados: El ICA-NSF presentó variaciones espacio temporales no significativas entre las estaciones de muestreo, con calidades de agua entre "regular" y "excelente". Los índices de diversidad mostraron que la equidad y riqueza son mayores en la estación E1. El BMWP/Univalle evidenció la influencia de las diferentes actividades sobre la subcuenca del río Jordán, clasificando la estación E1 como "Buena", E2 "Aceptable" y E3 "Dudosa". Las variables que mejor explicaron el patrón de diversidad fueron las asociadas a la contaminación orgánica (DBO5 y Coliformes totales). Conclusiones: Integralmente, los índices muestran que la mejor calidad del agua se presenta en la estación E1 donde la influencia de las actividades antrópicas es menor.

Introduction: Andean rivers in Colombia are heavily influenced along the drainage basin by various human activities. Aquatic macroinvertebrates have been used in different water environments to assess water quality in rivers. Objective: This study analyzed the behavior of different biotic indices to assess water quality of the lower middle section of the Jordan River in the department of Valle del Cauca, Colombia. Materials and methods: Sampling sites were situated at different altitudes as well with different anthropogenic influences. Physicochemical and microbiological parameters (n = 15) were measured, simultaneously with biological variables. Individuals were collected in gravel, pebbles and macrophytes (n = 15) using Surber nets (0.36 m2, 500 µm) a screen net (1.6 m2, 350 µm) and a D-net (0.9 m2, 500 µm). The water quality index (NSF ICA), biotic indices BMWP/Univalle, ASPT, EPT, and the Shannon-Weaver Equity index, Margalef Diversity index and Simpson's dominance index were evaluated to determine the macroinvertebrate assemblage through sampling sites. Spearman correlation between matrices of biotic and environmental similarity, using PRIMER® software was used to determine relationship between physicochemical variables and biodiversity. Results: The water quality index ICA-NSF showed spatio-temporal variations with water qualities between "regular" and "excellent". Diversity indices showed that equity and wealth are greater at site E1, where the influence of pollution is low. Biotic indices behaved variably, BMWP/Univalle index reflected more adequately the influence of human activities of the Jordan River sub-basin. Conclusions: The variables that best explained the pattern of diversity were those associated with organic pollution (BOD5 and total coliforms).

Functional Feeding Group composition and attributes: evaluation of freshwater ecosystems in Atlantic Forest, Brazil / Composição e atributos de Grupos Funcionais Alimentares: avaliação de ecossistemas de água doce na Mata Atlântica, Brasil

Abstract: Benthic macroinvertebrates Functional Feeding Group (FFG) have been used to determine aquatic assemblage dynamics and as a biomonitoring tool. The main goals of this study were to assess the effects of stream variables on the abundance and richness of FFGs and evaluate ecosystem attributes (FFG ratios) as a tool to assess ecological conditions of Atlantic Rainforest streams. We sampled 146 sites with different impairment conditions in Rio de Janeiro, Brazil. Richness was significantly different among impairment conditions for all FFGs. Mixed-effect models show that aquatic macroinvertebrate FFGs differed in their responses to abiotic variables for abundance and richness. Also, they were reduced in the impaired sites when compared to intermediate and reference sites. The FFG ratio indicated significant differences along the impairment gradient. The FFG ratio analysis was shown to be a fast and cheap tool that can be used for monitoring aquatic ecosystems in the Atlantic Forest biome. However, further studies are required to calibrate the method specifically for the Atlantic Forest region.

Resumo: Os Grupos Funcionais de Alimentação (GFA) são utilizados para determinar a dinâmica da comunidade de macroinvertebrados bentônicos e como uma ferramenta de biomonitoramento. Os principais objetivos deste estudo foram: avaliar os efeitos de variáveis de riacho na abundância e riqueza de GFAs e os atributos do ecossistema (razão GFA) como uma ferramenta para avaliar as condições ecológicas dos córregos da Mata Atlântica. Foram amostrados 146 locais com diferentes condições de impacto no Rio de Janeiro, Brasil. A riqueza foi significativamente diferente com as condições de impacto entre todos os GFA. Os modelos de efeito misto mostraram que os GFA diferiam em suas respostas às variáveis abióticas quanto à abundância e riqueza. Além disso, eles diferem nas áreas impactadas quando comparados as áreas intermediária e de referência. A razão de GFA encontrou diferenças significativas ao longo do gradiente de impacto. A análise da razão de GFA evidenciou-se uma ferramenta rápida e barata, com potencial para ser utilizada no monitoramento de ecossistemas aquáticos no bioma Mata Atlântica. No entanto, mais estudos serão necessários para calibrar o método especificamente para a região da Mata Atlântica.

Índices de calidad de habitat y macroinvertebrados en siete Cuencas del Parque Nacional Yanachaga Chemillén y su Zona de Amortiguamiento: conservación y manejo del bosque ribereño en el Perú / Habitat quality indexes y macroinvertebrates in seven Basins of the Yanachaga Chemillén National Park and its Buffer Zone: conservation and management of the riparian forest in Peru

Resumen Se presenta la caracterización del ambiente acuático, el ecosistema ribereño y las comunidades de macroinvertebrados en siete cuencas del flanco oeste del Parque Nacional Yanachaga Chemillén (PNYCh). Se aplicó el protocolo CERA que incluye el Índice Biótico Andino (IBA), el Índice de Hábitat Fluvial (IHF), el Índice de quebrada Andina (Qbr-And) y la combinación de los tres índices para determinar el Índice de Estado Ecológico de Ríos Andinos (ECOSTRIAND) en cada punto de muestreo. Asimismo, se estimaron los índices FBI y BMWP-Col para comparar la calidad de agua. Los muestreos se realizaron en las siete cuencas, entre los 1800 y los 2500 m de altitud, en la parte alta dentro del PNYCh, y en las cuencas media y baja, ambas en la zona de amortiguamiento del PNYCh. En las cuencas evaluadas se colectaron 179 taxa, 66 familias y 14 órdenes. Dentro del PNYCh los valores de IHF y Qbr-And fueron óptimos y en general fueron disminuyendo en calidad al alejarse del PNYCh. El IBA fue muy bueno en todas las cuencas y en todos los puntos de muestreo. Sin embargo, al combinar los 3 índices se observó una disminución del estado ecológico (ECOSTRIAND) de Muy bueno a Bueno y Regular. Los resultados finales muestran que el índice de estado ecológico disminuye al alejarse del PNYCh y esto coincide con un mayor disturbio de los bosques ribereños. Por último, se discute la protección legal de este tipo de ecosistemas ribereños en varios países de América y específicamente en Perú.

Abstract We present the characterization of the aquatic environment, riparian ecosystem and macroinvertebrate communities in 7 basins of the west slope of the Yanachaga Chemillén National Park (PNYCh). The CERA protocol, including the Andean Biotic Index (ABI), the Fluvial Habitat Index (IHF), the Andean Creek Index (Qbr-And) were estimated and the combination of these 3 indexes allowed to calculate the Ecological Status Index of Andean Rivers (ECOSTRIAND) at each sampling point. Additionally the FBI and BMWP-Col indexes were calculated. Sampling was carried out in the 7 basins, between 1800 and 2500 meters of altitude, including the upper basins inside the PNYCh, in the middle and lower basins, both in the buffer zone of the park. We found 179 taxa, 66 families and 14 orders in all basins evaluated. Within the PNYCh, the values of IHF and Qbr-And were optimal, but to go down basins, the indexes generally were decreasing in quality. The IBA was very good in all basins and all sampling points. However, when the 3 indexes were combining, the ECOSTRIAND index decreased, changed from very good to good and regular in some basins. The final results show that the ecological status index decreased as it moves away from PNYCh, this is associated with a greater riparian forests disturbance. Finally, we discussed the legal protection of this type of forest in several countries of America and specifically in Peru

Macroinvertebrates of Eichhornia crassipes (Pontederiaceae) roots in the alluvial floodplain of large tropical rivers (Argentina)

Introduction: Eichhornia crassipes is a dominant aquatic plant of neotropical-river floodplains and is invasive in warm waters of different continents. Plants provide food and habitat for fish, especially Prochilodus lineatus and Gymnotus omarorum, which are relevant to subsistence fishing by local indigenous communities. Objective: In this study we describe the main traits of E. crassipes floating meadows, and analyze the abundance and composition of macroinvertebrate assemblages associated with their roots in two floodplain wetlands of the Paraná River (within the Ramsar site Wetlands Chaco) and of the Pilcomayo River (within the Pilcomayo River National Park). Methods: During spring and summer, the macroinvertebrates were collected in monospecific stands of E. crassipes with a net of 962 cm2 area and 500 µm mesh size. Leaf density, the biomass of leaves and roots, the length of leaves and roots, and the water quality were measured simultaneously. Results: Temperature, oxygen concentration, and nutrient content were significantly higher and electrical conductivity was lower in the Pilcomayo than in the Paraná floodplain. E. crassipes growing in the Pilcomayo floodplain had longer leaves and less root biomass than those found in the Paraná floodplain. The number of macroinvertebrates per 1 000 g root dry weight and per m2 was significantly different between both floodplains, but the taxon richness was similar. Non Metric Multidimensional Scaling analysis differentiated the abundance of 14 selected taxa between both floodplains, and showed a high correlation between the environmental variables and macroinvertebrate abundance. The most abundant taxonomic groups in the Paraná River floodplain were oligochaetes (Naididae), ostracods mainly Cytheridella ilosvayi and larvae of non-biting midges (Chironomidae). Two families, Hydrobiidae (Heleobia parchappii) and Chironomidae accounted for 49.3 % of the total abundance in the Pilcomayo floodplain. The prawns Macrobrachium jelskii and M. amazonicum, frequent in the Pilcomayo floodplain, were not found in the Paraná floodplain. Conclusions: The different environmental conditions in both floodplains affect the abundance, composition, and the dominance of macroinvertebrate assemblages; however, the total taxa richness was similar. The area occupied by E. crassipes in the floodplains of these rivers provides the habitat that contributes most to overall biotic diversity, which must be considered in management strategies.

Introduccion: Eichhornia crassipes es la planta acuática dominante en la planicie de inundación de los ríos tropicales y ha invadido las aguas cálidas de diferentes continentes. Las plantas proveen alimento y hábitat para los peces, especialmente Prochilodus linneatus y Gymnotus omarorum, que son relevantes para la pesca de subsistencia de las comunidades indígenas locales. Objetivo: En el presente trabajo nosotros describimos las principales características de las formaciones flotantes de E. crassipes, y analizamos la abundancia y composición de los ensambles de macroinvertebrados asociados a sus raíces en dos humedales de las planicies de inundación de los ríos Paraná (dentro del sitio Ramsar Humedales Chaco) y Pilcomayo (dentro del Parque Nacional Río Pilcomayo). Métodos: Durante la primavera y el verano, los macroinvertebrados se recolectaron en formaciones monoespecíficas de E. crassipes con una red de 962 cm2 y 500 µm de tamaño de malla. La densidad de hojas, la biomasa de hojas y raíces, la longitud de las hojas y raíces y la calidad del agua se midieron simultáneamente. Resultados: La temperatura, la concentración de oxígeno disuelto y el contenido de nutrientes fueron significativamente mayores y la conductividad eléctrica fue significativamente menor en la planicie de inundación del Pilcomayo que en la del Paraná. Las plantas de E. crassipes que crecen en la planicie de inundación del Pilcomayo tuvieron hojas más largas y menos biomasa de raíces que las encontradas en la planicie del Paraná. El número de macroinvertebrados por 1 000 g. de peso seco de la raíz y por m2 fueron significativamente diferentes entre ambas planicies de inundación, pero la riqueza de taxa fue similar. El análisis de Escalamiento Multidimensional No Métrico diferenció la abundancia de los 14 taxa seleccionados entre ambas planicies de inundación, y mostró alta correlación entre las variables ambientales y la abundancia de los macroinvetebrados. Los grupos taxonómicos más abundantes en la planicie de inundación del río Paraná fueron los oligoquetos (Naididae), los ostrácodos, principalmente Cytheridella ilosvayi y las larvas de mosquitos no picadores (Chironomidae). Dos familias, Hydrobiidae (Heleobia parchappii) y Chironomidae representaron el 49,3 % de la abundancia total en la planicie de inundación del Pilcomayo. Los camarones Macrobrachium jelskii y M. amazonicum, frecuentes en la planicie de inundación del Pilcomayo, no se encontraron en la planicie de inundación del Paraná. Conclusiones: Las diferentes condiciones ambientales en ambas planicies de inundación afectan la abundancia, composición y la dominancia de los ensambles de macroinvertebrados; sin embargo, la riqueza total de taxa fue similar. El área ocupada por E. crassipes en la planicie de inundación de estos ríos proporciona el hábitat que más contribuye a la diversidad biótica, lo que debe ser considerado en las estrategias de manejo.

Diversity patterns of aquatic macroinvertebrates in a tropical high-Andean catchment

Introduction: Glacierised catchments are remote and hostile environments, in which streams from different water sources (e.g., glacier melt, rain/snowmelt, groundwater) converge, creating a complex mosaic of stream sites with varying levels of glacial influence and environmental conditions. This environmental heterogeneity, in turn, influences the assemblage and composition of aquatic communities and produces complex patterns of species diversity at the catchment scale. Objectives: In this contribution, we assessed biodiversity and community composition of aquatic macroinvertebrate communities from 51 stream site types in a glacierised catchment in the tropical Andes. The aim of our study was to: (1) determine diversity, rarity, commonness and spatial distribution patterns of aquatic macroinvertebrate communities from sites with different water sources, and (2) identify which environmental variables influence the density and presence of macroinvertebrate taxa and, in particular, of the subfamilies of the ubiquitous chironomids. Methods: Our study sites were grouped according to their water source and to their percentage of glacier coverage in the catchment (GCC). At each site we sampled aquatic macroinvertebrates, measured environmental variables and assessed community differences and environmental influence with ordination analyses and generalized linear models. Results: Kryal and mixed sites had an important proportion of rare taxa. Mean richness was highest in the mixed sites and lowest in the sites with the highest glacier cover; while sites with an intermediate percentage of glacier cover, had the highest values of α and β diversity. We found that 13 taxa (15.9%) were common to all stream site types. SIMPER analysis showed that Orthocladiinae, Hyalella sp. and Andesiops sp. contributed the most to the dissimilarity between site types (˃ 45% of cumulative contribution). RDA showed that kryal sites were associated with high turbidity and density of Podonomids, and with low temperature, amount of CPOM and densities of both Anomalocosmoecus sp. and Andesiops sp. Orthocladinae was associated with high current velocity and chlorophyll a concentration, whereas Hyalella sp. had a positive relationship with higher pH and streambed stability. Generalized linear models showed that GCC was the main variable explaining all faunal metrics. Current velocity explained macroinvertebrate abundance, water temperature was related to chironomid density and chlorophyll a influenced Orthocladiinae presence-absence. Conclusions: Our results suggest that by favoring the presence of rare taxa and taxa turnover, glacier influence may increase biodiversity in glacierised catchments. In terms of biodiversity conservation, this study confirms an urgent need to increase knowledge of high-Andean stream biodiversity, especially in highly heterogenous glacierised catchments, to better describe regional biodiversity patterns and community composition of these highly vulnerable freshwater ecosystems. Detailed analyses of benthic communities and development of databases are key for conservation strategies. Water management municipalities and/or enterprises should consider water quality and stream types for more sustainable management of these important ecosystems.

Introducción: Las cuencas glaciares son entornos remotos y hostiles, en los que los arroyos de diferentes fuentes de agua (p.ej., deshielo de glaciares, lluvia/deshielo, agua subterránea) convergen, creando un mosaico complejo de tramos con diferentes niveles de influencia glacial y condiciones ambientales. Esta heterogeneidad ambiental influye, a su vez, en el ensamblaje y composición de las comunidades acuáticas y produce complejos patrones de diversidad a la escala de la cuenca. Objetivos: En esta contribución, evaluamos la biodiversidad y composición de comunidades de macroinvertebrados acuáticos en 51 sitios de una cuenca glaciar en los Andes tropicales. Los objetivos de nuestro estudio fueron: (1) determinar la diversidad, la contribución de taxones raros y comunes y los patrones de distribución espacial de las comunidades de macroinvertebrados acuáticos en sitios con diferentes fuentes de agua, y (2) identificar qué variables ambientales influyen en la densidad y presencia de taxones de macroinvertebrados y, en particular, de las subfamilias de los omnipresentes quironómidos. Métodos: Agrupamos a nuestros sitios de estudio según su fuente de agua y su porcentaje de cobertura de glaciar en la cuenca (GCC). En cada sitio donde muestreamos macroinvertebrados acuáticos, medimos variables ambientales y evaluamos las diferencias entre comunidades y la influencia ambiental con análisis de ordenación y modelos lineales generalizados. Resultados: Los sitios kryal y mixtos tuvieron una proporción importante de taxones raros. La riqueza media fue más alta en los sitios mixtos y más baja en los sitios con mayor cobertura glaciar; mientras que los sitios con un porcentaje intermedio de cobertura glaciar tuvieron los valores más altos de diversidad α y β. Encontramos que 13 taxones (15,9%) fueron comunes a todos los tipos de sitios de estudio. El análisis SIMPER mostró que Orthocladiinae, Hyalella sp. y Andesiops sp. contribuyeron más a la disimilitud entre tipos de sitios (˃ 45% de la contribución acumulada). El RDA mostró que los sitios kryal estaban asociados con alta turbidez y densidad de podonómidos, y con baja temperatura, cantidad de CPOM y densidad de Anomalocosmoecus sp. y Andesiops sp. Orthocladinae se asoció con una alta velocidad de corriente y concentración de clorofila a, mientras que Hyalella sp. tuvo una relación positiva con pH más alto y estabilidad del lecho del río. Los modelos lineales generalizados mostraron que GCC fue la variable principal para explicar todas las métricas de fauna. La velocidad de corriente explicó la abundancia de macroinvertebrados, la temperatura del agua estuvo relacionada con la densidad de los quironómidos y la clorofila influenció la presencia-ausencia de Orthocladiinae. Conclusiones: Nuestros resultados sugieren que, al favorecer la presencia de taxones raros y la rotación de taxones, la influencia de los glaciares puede aumentar la biodiversidad en cuencas con influencia glaciar. En términos de conservación de la biodiversidad, este estudio confirma la necesidad urgente de incrementar el conocimiento de la biodiversidad en arroyos de la región altoandina, especialmente en cuencas glaciares altamente heterogéneas, para describir mejor los patrones de biodiversidad regional y la composición de las comunidades en estos ecosistemas altamente vulnerables. Análisis detallados de las comunidades bentónicas y el desarrollo de bases de datos son claves para diseñar estrategias de conservación. Los municipios y/o empresas administradoras de agua deben considerar la calidad del agua y los tipos de arroyos para una gestión más sostenible de estos importantes ecosistemas.

Preferencias alimentarias de Phylloicus sp. (Trichoptera: Calamoceratidae) en un río Neotropical de la Sierra Nevada de Santa Marta, Colombia

Introducción: En los sistemas fluviales colombianos ha sido poco estudiada la fragmentación del material alóctono por parte de los insectos acuáticos. Uno de los organismos trituradores más abundantes en las corrientes tropicales de América es el tricóptero del género Phylloicus (Calamoceratidae). Objetivo: El presente estudio tuvo como objetivo evaluar el efecto de los atributos químicos (nitrógeno, fósforo y lignina) y físicos (dureza) de las hojas de tres especies ribereñas (Ficus tonduzii, Zygia longifolia y Clusia multiflora) dominantes en la parte media del río Gaira, sobre la preferencia de hojas y el crecimiento de larvas de Phylloicus sp. Métodos: Se realizaron experimentos de multiselección de alimento en campo, en los que se ubicaron cámaras experimentales dentro del río por 21 días. Para la valoración de la calidad foliar se recolectaron hojas del río, las cuales se secaron y se pulverizaron para realizar los análisis químicos. Resultados: No se presentaron diferencias significativas en los porcentajes de lignina y fósforo entre las hojas de las tres especies de árboles, pero si en su dureza y en el contenido de nitrógeno. Las hojas de C. multiflora fueron más suaves (180.1± 53.9 g) que las de F. tonduzii (285.3 ± 88.4 g) y Z. longifolia (232.3 ± 60.8 g), pero sin diferencias entre las dos últimas especies. Las hojas de Z. longifolia también tuvieron más nitrógeno (1.9 ± 0.0%) que las de hojas de las otras especies (1 ± 0.0 %). En cuanto a la preferencia de hojas, las larvas de Phylloicus sp. utilizaron en mayor proporción las hojas de C. multiflora. Aunque las hojas de C. multiflora no tuvieron diferencias significativas en el contenido de lignina y fósforo, presentaron valores menores de dureza, lo que podría hacerlas más palatables para Phylloicus sp. Por otra parte, el crecimiento específico diario de las larvas fue mayor cuando usaron hojas de F. tonduzii. Conclusiones: Nuestros resultados parecen indicar que las hojas más preferidas no son necesariamente las de mejor calidad nutricional y sugieren que la dureza de las hojas es la variable más importante en la selección de la hojarasca por parte de las larvas de Phylloicus sp.

Introduction: Fragmentation of allochthonous material by aquatic insects is a functional process that has been little studied in Colombian rivers. One of the most abundant shredder genus in American tropical stream ecosystems is the caddisfly genus Phylloicus (Calamoceratidae). Objective: In this study we evaluate the effect of chemical (nitrogen, phosphorus and lignin) and physical (toughness) attributes of leaves of three dominant tree species (Ficus tonduzii, Zygia longifolia and Clusia multiflora) in the riverine area of the middle section of the Gaira river, on leaf preferences and larval growth of a species of Phylloicus. Methods: Multiple food selection field experiments were performed, in which experimental chambers were located in the river for twenty-one days. For the assessment of leaf quality, leaves were collected in the river, dried and pulverized to perform chemical analyzes. Results: There were no significant differences in lignin and phosphorous percentages between the leaves of the three species, but nitrogen content and leaf toughness differed among them. The leaves of C. multiflora were softer (180.1± 53.9 g) than those of F. tonduzii (285.3 ± 88.4 g) and Z. longifolia (232.3 ± 60.8 g), but without differences between the last two species. The Z. longifolia leaves also had more nitrogen (1.9 ± 0.0 %) than those of the other species (1 ± 0.0 %). Regarding leaf selection, Phylloicus sp. larvae used in greater proportion the leaves of C. multiflora. Although lignin and phosphorous differences were not significant, the leaves of C. multiflora had lower toughness, which could make them more palatable for Phylloicus sp. On the other hand, the daily specific growth of the larvae was higher when they used leaves of F. tonduzii. Conclusions: Our findings seem to indicate that the most preferred leaves were not necessarily those of better nutritional quality and suggest that leaf toughness was the most important variable in the selection of leaf litter by the larvae of Phylloicus sp.

Aquatic Oligochaete Communities in Amazonian Streams, Saracá-Taquera National Forest, Pará, Brazil / Comunidade de oligoquetos aquáticos em riachos amazônicos, Floresta Nacional Saracá-Taquera, Pará, Brasil

Abstract: The aim of this study was to analyze aquatic oligochaete distribution in relation to water column physicochemical variables, structural environmental variation, and predominant substrates in the preserved Amazonian streams of the Saracá-Taquera National Forest (FLONA Saracá-Taquera), northwest Pará, Brazil. Oligochaetes are widely used as bioindicators for monitoring aquatic environments as they are very sensitive to pollution and environmental changes. Physicochemical and structural variables were measured from 100 stream segments in order to understand the distribution of oligochaetes in Amazonian streams. Biotic samples were collected using Surber samplers in three of the most predominant substrate types in each segment. PERMANOVA testing showed that there was a significant difference in the oligochaete community among some substrates, potentially caused by a difference in the abundance of the most common taxa. Canonical Correspondence Analysis showed that physical variables drive the distribution of oligochaetes in preserved Amazonian streams, as they determine the formation of different substrates along the stream, from the source to the mouth; favoring the presence of oligochaetes with more specific ecological needs in low-order streams, and the presence of oligochaetes capable of colonizing various types of substrates and deeper zones in high-order streams. These results suggest that water depth and channel width are the main drivers of aquatic oligochaete distribution along Amazonian streams, determining the formation of unstable and low-quality substrates and, consequently, the low colonization by oligochaetes in high-order streams; and more diverse and stable substrate formation in low-order streams, favoring the colonization by diverse taxa of aquatic oligochaetes in low-order Amazonian streams.

Resumo: O objetivo deste trabalho foi analisar a distribuição da comunidade de oligoquetos em relação às variáveis físico-químicas da coluna da água, variação estrutural do ambiente, e substratos predominantes em riachos amazônicos conservados na FLONA Saracá-Taquera, noroeste do Pará, Brasil. Oligochaetes são amplamente utilizados como bioindicadores para monitoramento de ambientes aquáticos, pois são muito sensíveis à poluição e às mudanças ambientais. Variáveis físico-químicas e estruturais de 100 trechos de riachos foram mensuradas para entender a distribuição de oligoquetos em riachos amazônicos. Amostras bióticas foram coletadas com amostrador Surber em três dos tipos de substratos mais predominantes em cada trecho. A PERMANOVA mostrou que há uma diferença significativa da comunidade de oligoquetos entre alguns substratos, possivelmente baseada nas diferenças no número do táxon mais comum. A Análise de Correspondência Canônica mostrou que as variáveis físicas controlam a distribuição da comunidade de oligoquetos em riachos amazônicos preservados, porque estas variáveis determinam a formação dos diferentes substratos ao longo do riacho, desde a nascente até a foz, favorecendo a presença de oligoquetos com necessidades ecológicas mais específicas em riachos de baixa ordem, e oligoquetos capazes de colonizar diferentes tipos de substrato e zonas mais profundas em riachos de ordem maior. Os resultados deste trabalho sugerem que a profundidade da água e a largura do canal são as variáveis que controlam a distribuição da comunidade de oligoquetos em riachos amazônicos, determinando a formação de substratos instáveis e de baixa qualidade, e consequentemente baixa colonização de oligoquetos, em riachos de ordem maior; e formação de substratos mais diversificados, mais estáveis e de qualidade em riachos de baixa ordem, favorecendo a colonização de diversos taxa de oligoquetos aquáticos em riachos amazônicos de baixa ordem.

Calidad biológica y fisicoquímica de tres fuentes de agua y su relación con el fenómeno de El Niño y La Niña / Biological and physicochemical quality from three water sources and its relation to the El Niño and La Niña phenomenon

RESUMEN En el municipio de El Carmen de Viboral, Antioquia, la cuenca de la quebrada La Cimarronas y sus afluentes Los Andes y La Madera son las principales fuentes de abastecimiento del acueducto de la localidad. Además, en estas y en otras cinco estaciones de muestreo, ubicadas en la parte alta de la microcuenca y sus afluentes, se realizó la evaluación fisicoquímica, microbiológica y biológica, mediante el uso de los macroinvertebrados acuáticos, en tres periodos del ciclo hidrológico de El Niño (2016), los cuales, fueron comparados con tres muestreos del ciclo de La Niña (2011). Se pudo identificar la capacidad de resiliencia ambiental bajo un déficit y exceso de precipitaciones del sistema acuático. Durante el ciclo afectado por El Niño, se presentó mayor concentración de oxígeno disuelto, pH circumneutral, menor temperatura del agua y mayores concentraciones de nitritos, nitrógeno amoniacal y coliformes totales. Durante el ciclo afectado por La Niña, se manifestó mayor temperatura del agua, sólidos totales, dureza, nitratos, fósforo total y mejores condiciones de calidad biológica del agua, según el índice BMWP. No se registraron variaciones estadísticamente significativas del caudal, la temperatura del agua, la conductividad eléctrica y los índices comunitarios (diversidad, equidad, dominancia y riqueza).

ABSTRACT In the municipality of El Carmen de Viboral, Antioquia, the basin of the La Cimarronas stream and its tributaries Los Andes and La Madera, are the main sources of supply of the local aqueduct. In addition, of these, other five sampling stations located in the upper part of the basin and its tributaries, the physico-chemical, microbiological and biological evaluation was carried out through the use of aquatic macroinvertebrates in three periods of the El Niño hydrological cycle (2016), which were compared with three samplings of the La Niña cycle (2011). The capacity of environmental resilience could be identified under a deficit and excess precipitation of the aquatic system. During the cycle affected by El Niño there was a higher concentration of dissolved oxygen, circumneutral pH, lower water temperature and higher concentrations of nitrites, ammonia nitrogen and total coliforms. During the cycle affected by La Niña, there was a higher water temperature, total solids, hardness, nitrates, total phosphorus and better conditions of biological water quality according to the BMWP index. There were no statistically significant variations in flow, water temperature, electrical conductivity and community indices (diversity, equity, dominance and richness).

Clave taxonómica de ninfas de Ephemeroptera(Insecta) del sudeste de Perú / Taxonomic key of nymphs of Ephemeroptera (Insecta) from southeastern Peru

Ephemeroptera es un orden de insectos cuyas etapas inmaduras cumplen un importante papel ecológico en los ecosistemas acuáticos. Sin embargo, el conocimiento de su diversidad en áreas tropicales aún es escaso. Específicamente, en el Perú se han reportado 64 especies pertenecientes a 35 géneros y ocho familias. En este estudio se presenta una clave taxonómica para la determinación de géneros de ninfas de Ephemeroptera de la vertiente suroriental de los Andes del Perú. Las ninfas revisadas fueron recolectadas en las quebradas de los departamentos de Cusco y Madre de Dios, dentro de un gradiente altitudinal de 180 - 4411 m, en los años 2012, 2013, 2015 y 2017. Se utilizaron tres metodologías de muestreo: recolección manual, red Surber y colonización de paquetes de hojas. Se reconocieron 48 géneros de ocho familias en 36 quebradas dentro de este gradiente. Seis géneros son nuevos registros para el Perú: Prebaetodes, Zelusia, Meridialaris, Tricorythopsis, Homoeoneuria y Hubbardipes.

Ephemeroptera is an insect order of whose immature stages play an important ecological role in aquatic ecosystems. However, its diversity knowledge in tropical areas is scarce. In particular, only 64 species of 35 genera and eight families have been reported in Peru. In this work, we provide a general key of Ephemeroptera nymphs for southeastern Peru. Nymphs were collected from streams of Cusco and Madre de Dios departments, within an altitudinal gradient of 180 - 4411 m, in 2012, 2013, 2015 and 2017 years. The samples were obtained by manual collection, using a Surber net and by colonization of leaf packs. We recognized 48 genera within eight families, coming from 36 streams within the gradient. Six genera are new records to Peru: Prebaetodes, Zelusia, Meridialaris, Tricorythopsis, Homoeoneuria and Hubbardipes.

Metrics of benthic communities and habitat quality associated to different types of land use / Qualidade de habitat e métricas de macroinvertebrados bentônicos associadas a diferentes tipos de uso do solo

ABSTRACT Aquatic ecosystems are under severe anthropogenic modifications. Thus, the dependent biological communities in these environments are also changed. The objective of this study was to investigate the effects of urban development in a highly impacted ecosystem. We selected 15 sampling points along the stream Ribeirão Vermelho, in which were sampled benthic macroinvertebrates and assessed the water and habitat diversity. It was found an impact gradient, with some the reference points classified as natural and others as impacted. There was a significant difference in all biological indicators used. The total number of taxa, the wealth of Diptera, the taxa Ephemeroptera, Plecoptera and Trichoptera, and the diversity indices, the Water Quality Indices, and the percentage of herbivores crushers and predators were significantly higher in points classified as natural and changed. The relative abundances of collectors, filter feeding, chironomids and parasites were significantly lower in sites classified as natural in relation to impacted ones. The metrics of the macroinvertebrate community benthic and Habitat Diversity Protocol were influenced by environmental degradation, being a useful tool for planning and development actions for the preservation of watersheds and the prioritization of high-value transmission systems for protection and rehabilitation of aquatic ecosystems

RESUMO Os ecossistemas aquáticos estão sob fortes modificações antrópicas. Assim, comunidades biológicas dependentes desses ambientes também são alteradas. O objetivo deste estudo foi investigar os efeitos do desenvolvimento urbano em um ecossistema impactado. Foram selecionadas 15 seções de amostragem ao longo do Ribeirão Vermelho e em cada uma foi amostrada a comunidade de macroinvertebrados bentônicos e avaliada a diversidade de habitat e qualidade da água. Observou-se um gradiente de impacto ao longo do ribeirão, com alguns pontos de referência classificados como naturais e outros como impactados. Houve diferença significativa em todos os indicadores biológicos utilizados. O número total de táxons, riqueza de Diptera, Ephemeroptera, Plecoptera e Trichoptera, e os índices de diversidade, de qualidade da água e porcentagem de herbívoros, trituradores e predadores foram significativamente maiores nos pontos classificados como naturais e impactados. As abundâncias relativas de coletores, filtradores, quironomídeos e parasitas foram significativamente menores em sítios classificados como naturais em relação aos impactados. ­Observou-se que as métricas das comunidades bentônicas de macroinvertebrados e o Protocolo de Avaliação Rápida da Diversidade de Habitat foram influenciados pela degradação ambiental, sendo estas ferramentas úteis para ações de planejamento e desenvolvimento para a preservação de bacias hidrográficas e a priorização de sistemas de transmissão de alto valor para proteção e reabilitação de ecossistemas aquáticos.