ABSTRACT This study evaluates the water quality of the main tributary and efluent of the Santo Domingo Lagoon. The objectives were to analyze the physical-chemical and biological characteristics of the water to determine its influence on water quality, using the ICA-NSF, ICA-Dinius, ABI and IBF indices. For this, samplings were carried out during the months of April and June, evaluating a total of 15 parameters and identifying the benthic macroinvertebrates present in the water bodies. Physicochemical indicators show a slightly higher water quality in April (maximum value 42.2%) compared to June (maximum value 35.5%). Meanwhile, the biological evaluation showed poor water quality at the sampling points with values from 14 to 21 according to the ABI index, while the IBF index indicated excellent quality at the points, suggesting a discrepancy between biological and physicochemical quality. This discrepancy suggests the presence of contaminants that could affect biodiversity in the long term, so it is important to carry out constant and more in-depth monitoring to establish the health of the aquatic ecosystem.

RESUMEN El presente estudio evalúa la calidad del agua del principal afluente y efluente de la Laguna Santo Domingo. Los objetivos fueron analizar las características físico-químicas y biológicas del agua para determinar su influencia en la calidad del agua, utilizando los índices ICA-NSF, ICA-Dinius, ABI e IBF. Para esto, se realizaron muestreos durante los meses de abril y junio, evaluando un total de 15 parámetros e identificando los macroinvertebrados bentónicos presentes en los cuerpos de agua. Los indicadores fisicoquímicos muestran una calidad del agua ligeramente superior en abril (valor máximo 42,2%) respecto a junio (valor máximo 35,5%). Mientras que, la evaluación biológica exhibió mala calidad del agua en los puntos de muestreo con valores de 14 hasta 21 según el índice ABI, en tanto que el índice IBF indicó una calidad excelente en los puntos, sugiriendo una discordancia entre la calidad biológica (según el IBF) y fisicoquímica. Esta discrepancia sugiere la presencia de contaminantes que podrían afectar la biodiversidad a largo plazo, por lo que, es importante realizar un monitoreo constante y más profundo para establecer la salud del ecosistema acuático.

SUMMARY This is a review of studies related with the effects generated by the fast-growing exotic plantations (PECR) of Pinus radiata and Eucalyptus spp. on water quality of watersheds in south-central Chile, at different spatial and temporal scales. The analyzed data comes from a region between 36° - 40° S in the Central Valley and includes both mountain ranges, the Coastal and the Andes. Studies on the watershed’s capacity to export nutrients indicate that the conversion from native forests to forest plantations implies a net loss in nitrogen (N) and phosphorus (P) retention capacity. Consequently, watersheds with plantations coverage experience a net loss of these nutrients. Similarly, in watersheds dominated by Eucalyptus globulus, nitrogen retention decreases, especially NO3-N, and is partially reversed as a wider riparian vegetation is maintained. Studies of soil erosion and sediment transport losses show that clearcut harvesting has significant impacts on water quality, increasing sediment transport rates in streams. However, when soil conservation measures are practiced, erosion rates decrease significantly during forest harvesting. Some of the physical-chemical characteristics of the water, such as pH and temperature, are similar between streams with native forests and forest plantations. There is also a tendency for a decrease of richness and abundance of the macrobenthic invertebrates community due to the replacement of riparian vegetation by Eucalyptus spp.

RESUMEN Se presenta una revisión de estudios acerca de los efectos que generan las plantaciones exóticas de crecimiento rápido (PECR) de Pinus radiata y Eucalyptus spp. sobre la calidad del agua de cuencas en el centro-sur de Chile, a diferentes escalas espaciales y temporales. Los datos analizados provienen de una región comprendida entre los 36°- 40° S, en el Valle Central y en ambas cordilleras de la Costa y de los Andes. Los estudios acerca de la capacidad de las cuencas para exportar nutrientes indican que la conversión de bosques nativos por plantaciones forestales, implican una pérdida en la capacidad de retención de nitrógeno (N) y fósforo (P), por lo que las cuencas con cobertura de plantaciones presentan pérdidas netas de estos nutrientes. En cuencas donde predomina Eucalyptus globulus, la retención de N disminuye, especialmente NO3-N y se revierte parcialmente a medida que se mantiene un mayor ancho de vegetación ribereña. Los estudios de pérdidas de suelo por erosión y transporte de sedimentos muestran que la cosecha a tala rasa produce fuertes impactos sobre la calidad del agua, aumentando las tasas de transporte de sedimentos en los cauces de agua. Sin embargo, cuando se practican medidas de conservación de suelos las tasas de erosión disminuyen notablemente durante la cosecha forestal. Algunas de las características físico-químicas del agua, como pH y temperatura, son similares en esteros con bosques nativos y plantaciones forestales. Finalmente, se detectó una tendencia a la disminución de la riqueza y abundancia de la comunidad de macro invertebrados bentónicos debido al reemplazo de la vegetación ribereña de especies boscosas nativas por Eucalyptus spp.

Resumen La construcción de carreteras puede generar amenazas a la biodiversidad de una importante red hidrológica conformada por riachuelos conocidos comúnmente como quebradas en la amazonia peruana. El objetivo del estudio fue determinar la composición, riqueza, abundancia, diversidad, dominancia y similaridad de hábitats de comunidades de macroinvertebrados bentónicos de cinco quebradas ubicadas en el área de influencia del eje carretero Iquitos-Nauta (Loreto, Perú). Las colectas se realizaron en cuatro épocas (vaciante, seca, creciente y llena), usando una red tipo D-net. La comunidad de macroinvertebrados bentónicos estuvo compuesta por 68 taxones y 4 556 individuos, distribuidos en 4 filos (Arthropoda, Annelida, Mollusca y Nematoda). El análisis de similitud indica que hubo diferencias significativas (p < 0.05) entre las épocas de vaciante-seca con las de creciente-llena; siendo la época seca la de mayor valor de riqueza, abundancia y diversidad; y creciente la de mayor dominancia. Chironomidae, Leptophlebiidae, Elmidae y Palaemonidae; fueron los taxones más dominantes. El presente trabajo es un aporte al conocimiento de las comunidades de macroinvertebrados que habitan los pequeños ecosistemas lóticos de la selva baja peruana.

Abstract The construction of roads can generate threats to the biodiversity of an important hydrological network made up of streams known as quebradas in the Peruvian Amazon. The objective of the study was to determine the composition, richness, abundance, diversity, dominance, and similarity of habitats of benthic macroinvertebrate communities of five streams located around the Iquitos-Nauta highway axis (Loreto, Peru). The collections were made in four periods (empty, dry, growing, and full), using a D-net type network. The benthic macroinvertebrate community was composed of 68 taxa and 4556 individuals, distributed in 4 phyla (Arthropoda, Annelida, Mollusca and Nematoda). The similarity analysis indicates that there were significant differences (p < 0.05) between the empty-dry seasons and the growing-full seasons; The dry season being the one with the greatest value of wealth, abundance, and diversity; and increasing the one with greater dominance. Chironomidae, Leptophlebiidae, Elmidae and Palaemonidae; were the most dominant taxa. The present work is a contribution to the knowledge of the macroinvertebrate communities that inhabit the small lotic ecosystems of the Peruvian lowland forest.

Resumo Os macroinvertebrados bentônicos são partes integrantes das águas interiores, habitando uma diversidade de ecossistemas aquáticos onde as comunidades estão espacialmente estruturadas. Os macroinvertebrados de algumas regiões mediterrânicas, como o Norte de África, ainda não são bem estudados. Por esta razão propusemos estudar a estrutura comunitária em massas de água localizadas no Nordeste da Argélia. Para tanto, foram amostrados 12 corpos d’água diferentes, duas barragens, três rios e sete córregos durante o período de outubro de 2020 a setembro de 2021. Aos dados bióticos e abióticos foi aplicada uma análise de redundância (RDA) com o objetivo de determinar o papel de ambos os tipos de variáveis para agrupar os sites. Além disso, foram considerados dois tipos de modelos nulos: co-ocorrência de espécies e compartilhamento de nicho para estudar as potenciais associações entre as espécies relatadas. A análise de redundância mostrou que a velocidade e a condutividade da água foram os principais impulsionadores da estrutura da comunidade de macroinvertebrados. Os resultados da co-ocorrência de espécies revelam que as associações de espécies são aleatórias, excepto em dois locais: El fadjoudj e Ain ben baida correspondentes ao rio Seybouse. Ao mesmo tempo, não há partilha de nicho e, consequentemente, não há competição interespecífica, excepto nos dois locais: riacho Salah Salah Salah e barragem de Bouhamdane. Os resultados revelaram semelhanças com outros estudos semelhantes para rios e barragens argelinos, e com outras massas de água semelhantes com clima mediterrânico. interiores estruturadas mediterrânicas África estudados Argélia tanto 1 dágua d diferentes 202 2021 RDA (RDA sites disso nulos coocorrência co ocorrência relatadas aleatórias locais Seybouse tempo consequentemente interespecífica Bouhamdane argelinos mediterrânico 20 2

Abstract Benthic macroinvertebrates are integral parts of inland waters, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Due this reason we proposed study the community structure in water bodies located in Northeastern Algeria. For this objective, we sampled 12 different kind of water bodies, two dams, three rivers, and seven streams during the period from October 2020 to September 2021. To biotic and abiotic data, a redundancy analysis (RDA) was applied with the aim of determine the role of both kind of variables for grouping the sites. Also, two types of Null models were considered: species co-occurrence and niche sharing for study the potential associations between species reported. Redundancy analysis showed that water velocity and conductivity were the main drivers of community structure of macroinvertebrates. The species co-occurrence results reveal that species associations are ramdom, except for two sites: El fadjoudj and Ain ben baida corresponding to Seybouse river. At the same time, there is no niche sharing and in consequence, there is no interspecific competition except in the two sites: Salah Salah Salah stream and Bouhamdane dam. The results revealed similarities with other similar studies for Algerian rivers and dams, and with other similar water bodies with Mediterranean climate. waters structured studied Algeria objective 1 dams 202 2021 data RDA (RDA sites Also considered cooccurrence co occurrence reported ramdom river time consequence dam climate 20 2

Resumo Objetivo A alta sensibilidade das nascentes à impactos antrópicos deve-se, em grande parte, a elevada conectividade aquático-terrestre existente. A degradação desses ecossistemas pode ser causada pelo uso do solo, como por exemplo o monocultivo de eucalipto. O objetivo deste estudo foi testar a influência de plantações de Eucalyptus urograndis sobre a riqueza, a diversidade da comunidade de macroinvertebrados bentônicos e as variáveis ambientais aferidas em nascentes nos domínios de Floresta Atlântica. Métodos Dez nascentes (5 em áreas de floresta nativa e 5 em áreas de eucalipto) foram amostradas no período seco de 2017. Os organismos foram triados e identificados ao nível de família. Para cada nascente foram mensuradas o oxigênio dissolvido, temperatura, pH, turbidez, condutividade elétrica, sólidos totais dissolvidos, nitrogênio total, nitrito, nitrato, amônia, fósforo total, cobertura vegetal, caracterização granulométrica e matéria orgânica. Resultados O teste t evidenciou algumas variáveis ambientais diferiram, apresentando as áreas de eucalipto maiores valores de sólidos totais dissolvidos e condutividade elétrica e menores de areia muito grossa. No presente estudo, a riqueza e diversidade da fauna bentônica em nascentes foram significativamente menores nas áreas de eucalipto do que nas áreas de vegetação nativa. Entretanto, a composição das comunidades não diferiu. A análise de espécies indicadoras (IndVal) associou Acari, Hydropsychidae, Leptoceridae, Nematoda, Psychodidae e Tipulidae a áreas de floresta nativa. Conclusões Nossos resultados mostram que nascentes em áreas de eucalipto são afetadas pela monocultura reduzindo a riqueza e diversidade de macroinvertebrados bentônicos e alterando também os parâmetros ambientais. Por fim, verificamos que estudos anteriores em outras partes do mundo também se aplicam a áreas neotropicais onde o eucalipto não é nativo. devese, devese deve se, deve-se parte aquáticoterrestre aquático terrestre existente solo Atlântica ( 2017 família dissolvido temperatura pH turbidez total nitrito nitrato amônia vegetal orgânica diferiram grossa Entretanto diferiu IndVal (IndVal Acari Hydropsychidae Leptoceridae Nematoda fim nativo 201 20 2

Abstract Aim The high sensitivity of springs to anthropic impacts is largely due to the high existing aquatic-terrestrial connectivity. The degradation of these ecosystems can be caused by land use, such as eucalyptus monoculture. The aim of this study was to test the influence of Eucalyptus urograndis plantations on the richness and diversity of the benthic macroinvertebrate community and on the environmental variables measured in springs in the Atlantic Forest domains. Methods Ten springs (5 in native forest areas and 5 in eucalyptus area) were sampled in the dry period of 2017. The organisms were screened and identified at the family level. For each spring, dissolved oxygen, temperature, pH, turbidity, electrical conductivity, total dissolved solids, total nitrogen, nitrite, nitrate, ammonia, total phosphorus, vegetation cover, granulometric characterization and organic matter were also measured. Results: The t-test showed that some environmental variables differed, with the eucalyptus areas having higher values of total dissolved solids and electrical conductivity, and lower values of coarse sand. In the present study, the richness and diversity of the benthic fauna of springs were significantly lower in eucalyptus sites than in native sites. Nonetheless, the composition of the communities did not differ. The Indicator Species Analysis (IndVal) associated Acari, Hydropsychidae, Leptoceridae, Nematoda, Psychodidae, and Tipulidae with areas of native forest. Conclusions Our results show that Brazilian springs are affected by eucalyptus monocultures reducing the richness and diversity of benthic macroinvertebrates and also changing water environmental properties. Thus, we verified that previous studies elsewhere in the world also apply to neotropical areas where eucalyptus is not native. aquaticterrestrial aquatic terrestrial connectivity use monoculture domains ( area 2017 level spring oxygen temperature pH turbidity conductivity nitrogen nitrite nitrate ammonia phosphorus cover Results ttest t differed sand Nonetheless differ IndVal (IndVal Acari Hydropsychidae Leptoceridae Nematoda Psychodidae properties Thus 201 20 2

ABSTRACT The invertebrate fauna in Northern Chilean inland waters has poorly studied due the difficult access, and there are only studies on crustacea species based in scarce expeditions. The aim of the present study is do a first community study on aquatic invertebrate communities reported in Salado River, a subsaline river in north of Chile, that is a tributary of Loa River the most long river in Chile (23°S, Antofagasta region), based on size overlap null models. The results revealed the presence of Diptera larvae (Simulium sp., Gigantodax sp., and Ortochladinae), coleoptera larvae (Elmidae), Odonata larvae, Aranae, and amphipod Hyalella kochi. The results revealed that there is a size overlap, this means that the reported species would share their ecological niches. It is the first description of niche overlap for invertebrate Chilean rivers, and the exposed results are similar for descriptions for decapods in marine environments.

RESUMEN La fauna de invertebrados en aguas interiores del norte de Chile ha sido poco estudiada debido al difícil acceso, y solo existen estudios sobre especies de crustáceos basados en escasas expediciones. El objetivo del presente trabajo es realizar un primer estudio comunitario de las comunidades de invertebrados acuáticos reportadas en el río Salado, un río subsalino del norte de Chile, afluente del río Loa, el río más largo de Chile (23°S, región de Antofagasta), basado en modelos nulos de superposición de tamaño. Los resultados revelaron la presencia de larvas de dípteros (Simulium sp., Gigantodax sp. y Ortochladinae), larvas de coleópteros (Elmidae), larvas de Odonata, Aranae y el anfípodo Hyalella kochi. Los resultados revelaron que existe una superposición de tamaño, esto significa que las especies reportadas compartirían sus nichos ecológicos. Es la primera descripción de superposición de nicho para ríos chilenos de invertebrados, y los resultados expuestos son similares para descripciones de decápodos en ambientes marinos.

RESUMEN Los componentes alfa (α) y beta (ß) de la diversidad gamma (γ), y la partición de ß en anidamiento y recambio, contribuyen a entender los factores que determinan la diversidad biológica. El objetivo de este estudio fue entender los factores que afectan los cambios espaciales de diversidad de macroinvertebrados en lagos andinos tropicales de alta montaña, a partir del estudio de los componentes de diversidad y la partición de la diversidad ß. Para esto, se realizó un muestreo en noviembre de 2018, en un lago ubicado a 3740 m.s.n.m. Se recolectaron macroinvertebrados bentónicos en 20 sitios distribuidos en las zonas litoral, sublitoral y profunda. In situ, se midieron profundidad, temperatura, pH, conductividad y oxígeno disuelto; se realizaron perfiles verticales de oxígeno y temperatura. Se evaluaron los componentes de riqueza mediante el modelo γ= α +ß. Se realizaron: análisis de regresión entre a y g, análisis de disimilitud a partir de la partición de la diversidad ß en recambio y anidamiento, Escalamiento Multidimensional no Métrico (nMDS) y Porcentaje de Similaridad (Simper). Los resultados mostraron que la diversidad a por sitios y zonas del lago es baja con relación a la diversidad g, y la diversidad ß es alta. Esto indica que los lagos tropicales andinos de alta montaña, a pesar de su pequeño tamaño, son importantes para una alta diversidad de macroinvertebrados. La riqueza taxonómica depende de las variaciones ambientales en los gradientes vertical y horizontal. Sin embargo, estos lagos son vulnerables a tensores naturales y antrópicos como el calentamiento global.

ABSTRACT The alpha (α) and beta (ß) components of gamma (γ) diversity, and the partitioning of ß into nesting and turnover, contribute to understanding the factors that determine biological diversity. The objective of this study was to understand the factors affecting spatial changes in macroinvertebrate diversity in tropical high mountain Andean lakes, from the study of diversity components and beta diversity partitioning. For this, sampling was conducted in November 2018, in a lake located at 3740 m.a.s.l. Benthic macroinvertebrates were collected in 20 sites distributed in littoral, sublittoral and deep zones. In situ, depth, temperature, pH, conductivity and dissolved oxygen were measured; vertical profiles of oxygen and temperature were made. Richness components were evaluated using the γ= α +ß model. Regression analysis between a and g, dissimilarity analysis from the partitioning of beta diversity into turnover and nesting, Non-Metric Multidimensional Scaling (nMDS) and Percent Similarity (Simper) were performed. The results showed that a diversity by sites and lake zones is low relative to g diversity, and ß diversity is high. This indicates that high mountain tropical Andean lakes, despite their small size, are important for high macroinvertebrate diversity. Taxonomic richness depends on environmental variations in gradients vertically and horizontally. However, these lakes are vulnerable to natural and anthropogenic stressors such as global warming.

RESUMEN La calidad del agua de mar fue descrita en la costa caribeña de Panamá con base en parámetros fisicoquímicos del agua y estudios de monitoreo biológico. Se recolectaron muestras de agua y macroinvertebrados bentónicos cerca de Punta Galeta, provincia de Colón, Panamá. El área de muestreo estaba protegida de la acción de las olas y ubicada entre el arrecife de coral y los manglares. La clase Polychaeta fue la más abundante con 90 % de presencia general en Punta Galeta. Las clases taxonómicas de Bivalvia, Malacostraca y Ophiuroidea sólo representaron 10 % en total. En general, la calidad del agua de mar fue adecuada para las especies recolectadas de macroinvertebrados, a pesar de registrar concentraciones de nitrato y fosfato por encima de los valores recomendados. Los valores registrados de temperatura, pH y oxígeno disuelto indicaron que el sitio está lejos de alcanzar condiciones hipóxicas. El índice de calidad del agua indica una buena calidad del agua en Punta Galeta. Se requieren estudios adicionales con programas de muestreo más robustos e intensos para definir adecuadamente las variaciones estacionales de la calidad del agua y su vínculo con los macroinvertebrados bentónicos. Estudios similares en el Caribe de Panamá son escasos a pesar de que ofrecen información valiosa para los administradores de recursos hídricos.

ABSTRACT S eawater quality was described in the Caribbean coast of Panama based on water physicochemical parameters and biological monitoring studies. Samples of water and benthic macroinvertebrates were collected near Punta Galeta, Province of Colón, Panama. The sampling area was sheltered from the action of waves and located between the coral reef and mangroves. Class Polychaeta was the most abundant with 90 % overall presence in Punta Galeta. Taxonomic classes of Bivalvia, Malacostraca and Ophiuroidea only represented 10 % altogether. Overall, seawater quality was suitable for the collected species of macroinvertebrates, even though concentrations of nitrate and phosphate were above the recommended value. Recorded values of temperature, pH and dissolved oxygen indicated that the site is far from reaching hypoxic conditions. Water quality index indicates a good water quality at Punta Galeta. Further studies with more robust and intense sampling programs are required to properly define the seasonal variations of water quality and its link to benthic macroinvertebrates. Similar studies in the Caribbean of Panama are scarce even though they offer valuable information for water resource administrators.

Resumen La cuenca baja del rio Cusiana es un área afectada por diferentes actividades socioeconómicas. El trabajo tiene como objetivo establecer la estructura fisicoquímica y biológica de las áreas influenciadas por agricultura, ganadería y descargas de aguas residuales de áreas urbanas. El muestreo se realizó en dos localidades, la primera en el municipio de Aguazul y la segunda en el municipio de Maní en el departamento del Casanare (Colombia). Se realizaron cuatro monitoreos considerando diferencias estacionales en precipitación y sequía, las variables analizadas fueron: Temperatura, Alcalinidad, Conductividad, Turbiedad, DBO, DQO, Dureza Total, Fósforo Total, Nitratos, Oxígeno Disuelto, pH, Sólidos Suspendidos y muestreo de comunidades de macroinvertebrados bentónicos. Para determinar la calidad en los periodos muestreados, se estimaron indicadores fisicoquímicos ICA NSF, teniendo en cuenta los usos que presenta el recurso hídrico, reportando calidad media. Se reportaron 1491 individuos, distribuidos en siete órdenes y 20 familias. Al calcular el índice BMWP/Col para las dos estaciones de monitoreo, la estación Aguazul presenta una calidad dudosa cuya significancia ambiental correspondió a Aguas Ligeramente Contaminadas, disminuyendo significativamente a Aguas Moderadamente Contaminadas. La Estación Maní pasó de estado dudoso a estado crítico y de aguas moderadamente contaminadas a muy contaminadas. Estudios de esta naturaleza permiten a las entidades tomar decisiones acertadas sobre el uso y manejo adecuado de los sistemas hídricos de la región.

Abstract The lower basin of the Cusiana River is an area affected by various socioeconomic activities. This study aims to establish the physicochemical and biological structure of areas influenced by agriculture, livestock, and wastewater discharges from urban areas. Sampling was conducted at two locations, the municipality of Aguazul and the municipality of Maní in the Casanare department, Colombia. Four monitoring surveys were carried out considering seasonal differences in rainfall and drought. The variables analyzed were: temperature, alkalinity, conductivity, turbidity, BOD, COD, total hardness, total phosphorus, nitrates, dissolved oxygen, pH, suspended solids and sampling of benthic macroinvertebrate communities. To assess water quality in the sampled periods, physicochemical indicators ICA NSF were estimated, considering the intended uses of the water resource, and reporting average quality. A total of 1491 individuals were reported, distributed across seven orders and 20 families. The BMWP/Col index was calculated for the two monitoring stations. The Aguazul station showed doubtful water, categorized as slightly polluted waters, which decreased significantly to moderately polluted waters. The Maní Station transitioned from dubious to critical condition and from moderately polluted to very polluted waters. Studies of this nature allow entities to make informed decisions regarding the proper using and management of the region’s water systems.

Abstract Aquatic macroinvertebrates are integral parts of functioning wetlands, inhabiting a diversity of aquatic ecosystems where communities are spatially structured. Macroinvertebrates of some Mediterranean regions such as North Africa are still not well studied. Here, we study the community structure of benthic macroinvertebrates in four different types of lotic and lentic wetlands in the semiarid Haut Plateaux of Northeast Algeria. Macroinvertebrates and 06 physicochemical parameters were sampled in 12 sites belonging to four types of habitats (lotic river, lentic river, dams, and sebkha [saline lentic water body]) during January-December 2021. Eventually, the character lentic-lotic was the most important variable affecting the affecting invertebrate communities in the Mediterranean region. The results revealed that sebkha and dams had a lower Shannon index than lentic and lotic rivers. Non-metric multidimensional scaling analysis showed a strong overlap between the community composition in lotic and lentic sites . Howeverin the three types of aquatic groups lentic river, dam and lotic habitats showed a strong overlap between the community whereas sebkha was markedly separated. Redundancy analysis showed that water velocity and pH, were the main drivers of community structure of macroinvertebrates, revealed a strong effect with pH (F1,8=4.15, P = 0.001) and water velocity (F1,8= 3.22, P = 0.002) , separating lotic communities from those that inhabited dams, lentic rivers, and sebkhas. As conclusion, this study contributes to the better understanding of the community structure of macroinvertebrates in semiarid North Africa where wetlands have been experiencing high anthropogenic disturbance.

Resumo Macroinvertebrados aquáticos são partes integrantes de zonas úmidas em funcionamento, habitando uma diversidade de ecossistemas aquáticos onde as comunidades são espacialmente estruturadas. Os macroinvertebrados de algumas regiões mediterrâneas, como o norte da África, ainda não foram especificamente analisados. Neste trabalho, almejou-se analisar a estrutura da comunidade de macroinvertebrados bentônicos em 4 tipos diferentes de pântanos lóticos e lênticos no semiárido Haut Plateaux do nordeste da Argélia. Os macroinvertebrados e 6 parâmetros físico-químicos foram amostrados mensalmente em 12 locais pertencentes a 4 categorias de habitats diferentes (rio lótico, rio lêntico, barragens e sebkha - corpo de água salina lêntica) de janeiro a dezembro de 2021. Os resultados revelaram que sebkha e barragens tiveram um pH mais baixo do que os rios lênticos e lóticos. A análise de escala multidimensional não-métrica mostrou uma forte sobreposição entre a composição da comunidade em sítios lóticos e lênticos, mas nos 3 tipos de sítios lênticos, barragem e rio lêntico mostraram uma forte sobreposição, enquanto sebkha foi marcadamente separado. A análise de redundância mostrou que a velocidade da água e o pH foram os principais impulsionadores da estrutura da comunidade de macroinvertebrados, separando as comunidades lóticas daquelas que habitavam barragens, rios lênticos e sebkhas. Assim, à guisa de conclusão, este estudo contribui para a melhor compreensão da estrutura da comunidade de macroinvertebrados no semiárido norte da África, onde as zonas úmidas têm sofrido alta perturbação antrópica.

ABSTRACT Environmental degradation from human pressures includes the conversion of native vegetation cover into pastures and cropland, as well as riparian deforestation, leading to river siltation, biotic homogenization, and loss of ecosystem services. The objective of our study was to evaluate water quality and benthic macroinvertebrate assemblage structure in response to changes in land use at local and buffer spatial extents. We assumed that human disturbances negatively affect water quality and macroinvertebrate assemblage condition. Greater human influence was observed at the local extent (Local Disturbance Index – LDI) than at the buffer (Buffer Disturbance Index – BDI) extent. Likewise, biological metric responses were stronger relative to the LDI than to the BDI or to the Integrated Disturbance Index (IDI). These results support establishing a biomonitoring program for assessing water body quality in the Doce River basin to facilitate conserving aquatic biodiversity and ecosystem services in the upper Graipu River.

RESUMO A degradação ambiental causada por pressões antrópicas inclui a conversão de cobertura vegetal nativa em pastagens e terras agrícolas, bem como o desmatamento de zonas ripárias, levando ao assoreamento de rios, à homogeneização biótica e à perda de serviços ecossistêmicos. O objetivo do nosso estudo foi avaliar a qualidade de água e a estrutura de assembleia de macroinvertebrados bentônicos em resposta a mudanças no uso da terra em extensões espaciais locais e de microbacia (buffer). Para tanto, assumimos que os distúrbios humanos afetam negativamente a qualidade de água e a assembleia de macroinvertebrados bentônicos. Maior influência humana foi observada na escala local (Índice de Distúrbio Local – LDI) do que na escala de buffer (Índice de Distúrbio Buffer – BDI). Da mesma forma, as respostas das métricas biológicas foram mais correlacionadas ao LDI do que ao BDI ou o Índice Integrado de Distúrbio (IDI). Esses resultados apoiam o estabelecimento de um programa de biomonitoramento para avaliar a qualidade de corpos hídricos na bacia do rio Doce, fomentando a conservação de biodiversidade aquática e serviços ecossistêmicos no alto ribeirão Graipu.

Abstract Aim In the present study, the structure of the benthic invertebrates in ponds in the presence and absence of Nile tilapia was evaluated. Methods The benthic macroinvertebrates and physicochemical parameters were analyzed for a period of eight weeks, every 15 days, in two ponds (one with fish and the other without fish). Benthic invertebrates were sampled with artificial substrate samplers, made with cheap and common materials, like expanded clay, loofah leaves and gravel. Results With the exception of turbidity, the other physical and chemical variables of water quality were within the ideal limits for tilapia farming. Despite that, there was a significant difference for all physical-chemical parameters monitored, and the average turbidity was much higher in pond with fish. The use of artificial substrate samplers for biomonitoring was effective in the colonization of several taxa in a short period of time (15 days). For benthic community metrics, organism richness, diversity and evenness were significantly higher in the pond without fish. On the other hand, the dominance of Chironomidae and the abundance of Glossiphonidae were much higher in the pond with fish. For Chironomidae, this family was dominant in both treatments, but reached a higher frequency in the pond with fish (98.49%) than in pond without fish (92.87%). The presence of sensitive families, like Leptoceridae (Order Trichoptera), was higher in the pond with no fish, as well as the metric of Ephemeroptera, Plecoptera and Trichoptera families (% EPT). Conclusions The presence of fish altered the macrobenthic community, since metrics of richness and diversity presented lower values in pond with fish.

Resumo Objetivo No presente estudo, avaliou-se a estrutura de invertebrados bentônicos em viveiros escavados na presença e ausência de tilápia do Nilo. Métodos Os macroinvertebrados bentônicos e os parâmetros físico-químicos foram analisados por um período de oito semanas, a cada 15 dias, em dois viveiros (um com peixes e outro sem peixes). Os invertebrados bentônicos foram coletados com amostradores de substrato artificial, feitos com materiais baratos e comuns, tais como argila expandida, folhas de taboa e brita. Resultados Com exceção da turbidez, as demais variáveis físicas e químicas da qualidade da água estiveram dentro dos limites ideais para o cultivo de tilápia. Apesar disso, houve diferença significativa para todos os parâmetros físico-químicos monitorados, sendo que a turbidez média foi bem maior no tanque com peixes. Para as métricas dos macroinvertebrados bentônicos, riqueza, diversidade e uniformidade de organismos foram significativamente maiores no tanque sem peixes. Por outro lado, a dominância de Chironomidae e a abundância de Glossiphonidae foram muito maiores no tanque com peixes. Para Chironomidae, esta família foi dominante em ambos os tratamentos, mas atingiu maior frequência no viveiro com peixes (98,49%) do que no viveiro sem peixes (92,87%). A presença de famílias sensíveis, como Leptoceridae (Ordem Trichoptera), foi maior no viveiro sem peixes, assim como a métrica das famílias Ephemeroptera, Plecoptera e Trichoptera (% EPT). Conclusões O uso de amostradores de substrato artificial para biomonitoramento mostrou-se eficaz na colonização de diversos táxons em um curto período de tempo (15 dias). Por fim, a presença de peixes alterou a comunidade macrobentônica, já que as métricas de riqueza e diversidade apresentaram valores mais baixos no viveiro escavado com peixes.

Resumen Los humedales altoandinos son sistemas frágiles, vulnerables a la actividad humana y al cambio climático. La región de Arequipa (Perú) posee ecosistemas lóticos y lénticos altoandinos con impactos por la ganadería, piscicultura y represamiento. Se evaluó la comunidad de macroinvertebrados acuáticos de los humedales de Callalli-Oscollo y el posible efecto de las actividades humanas. Desde noviembre de 2017 a octubre de 2018 se realizaron muestreos en 4 estaciones en ambientes lóticos y 2 en lénticos. Los macroinvertebrados se identificaron a nivel de familia. Para evaluar la estructura comunitaria se registró la riqueza, la abundancia relativa, la diversidad de Shannon-Wiener, la dominancia de Simpson, la equidad de Pielou y la diversidad verdadera. Se aplicaron los índices ABI, BMWP/Bol y nPeBMWP para evaluar la calidad ecológica de los ambientes lóticos. En éstos se registraron 30 familias, siendo las más abundantes Chironomidae, Naididae, Limnesiidae, Elmidae, Baetidae y Lumbriculidae. La calidad ecológica fue buena, con excepción de la estación vinculada a la presa que fue dudosa. Los ambientes lénticos registraron 26 familias, siendo las más abundantes Cyprididae, Naididae y Corixidae. Las comunidades de macroinvertebrados en ambientes altoandinos reflejan el estado del ecosistema. Los ambientes vinculados con la actividad humana registran menor calidad ecológica.

Abstract High Andean wetlands are fragile systems, vulnerable to human activity and climate change. In the Arequipa region (Peru), there are high Andean lotic and lentic systems currently affected by livestock raising, fish farming, and dams. The aim of the study was to evaluate the aquatic invertebrate community in the Callalli-Oscollo wetlands and the possible impact of human activities. Samples were taken from November 2017 to October 2018 at 4 sampling stations in lotic environments and 2 in lentic environments. Macroinvertebrates were identified to the family level. The following were determined to evaluate community structure: richness, relative abundance, Shannon-Wiener diversity, Simpson dominance, Pielou evenness, and true diversity. The indices ABI, BMWP/Bol and nPeBMWP were applied to evaluate the ecological quality of the environments sampled. Thirty families were recorded in lotic environments, the most abundant being Chironomidae, Naididae, Limnesiidae, Elmidae, Baetidae and Lumbriculidae. The ecological quality was good, except at the station associated to the dam, where it was doubtful. Twenty-six families were recorded in lentic environments, the most abundant being Cyprididae, Naididae and Corixidae. The macroinvertebrate communities in high Andean environments reflect ecosystem conditions. Environments associated to human activity have lower ecological quality.

Resumen Se establecieron dos estaciones en un sector del rio Chotano, con el objetivo de evaluar la calidad del agua, empleando macroinvertebrados bentónicos como bioindicadores, para lo cual se utilizaron índices biológicos: IBMWP, ETP %, diversidad, riqueza, equidad, dominancia, la densidad y grupos tróficos. La recolección de los macroinvertebrados se realizó empleando la red tipo Surber, en dos períodos (seco y lluvioso). En la estación 1 se colectaron en promedio 710 ind/m2 distribuidos en 23 taxones de los órdenes díptera, efemeróptera y tricóptera y en la estación 2 se colectaron 16790 ind/m2 , con 6 taxones de los órdenes haplotaxida y díptera, siendo las especies indicadores de polución orgánica, Chironomus sp, Tubifex sp y Psychoda sp, presentes mayormente en la estación 2. Los índices promedios más altos en la estación 1 a comparación de la estación 2 fueron, IBMWP con 60 puntos indicador de calidad de agua dudosa, moderadamente contaminada y 11 puntos, indicador de calidad muy crítica fuertemente contaminada, la diversidad de Shannon - Wiener 1,33 y 0,30 indicador de aguas con poca diversidad, la equidad de Pielou 0,50 muestran poblaciones más estables y 0,20 menos estables; los índices más bajos en la estación 1 comparando con la estación 2 fueron, dominancia de Simpson 0,37 indicador de poca dominancia y mayor diversidad y 0,9 indicador de mayor dominancia, menor diversidad y mayor polución orgánica.

Abstract Two stations were established in a sector of the Chotano river, with the objective of evaluating the quality of the water, using benthic macroinvertebrates as bioindicators, for which biological indices were used: IBMWP, ETP %, diversity, richness, equity, dominance, density and trophic groups. The collection of macroinvertebrates was carried out using the Surber sampler, in two periods (dry and rainy). In the first season, an average of 710 ind/m2 were collected, classified in 23 taxa of the orders diptera, ephemeroptera and tricoptera, and in the second season 16790 ind/m2 were collected, with 6 taxa of the orders haplotaxide and diptera, the species indicating organic pollution, Chironomus sp, Tubbier sp and Psychoda sp, present mostly in season 2. The highest average indices in season 1 compared to season 2 were IBMWP with 60 points indicating moderately polluted doubtful water quality and 11 points indicating highly polluted critical quality, the diversity of Shannon - Wiener 1,33 and 0,30 indicating waters with limited diversity, the equity of Pielou 0,50 show more stable and 0,20 less stable populations; the lowest indices in station 1 compared to season 2 were, Simpson dominance 0,37 indicator of low dominance and higher diversity and 0,9 indicator of higher dominance, lower diversity and higher organic pollution.

RESUMO A Reserva Biológica (REBIO) do Mato Grande é uma unidade de conservação localizada no município de Arroio Grande, no sul do Rio Grande do Sul. A sua zona de amortização possui 40 propriedades rurais cadastradas no sistema irrigante da Fundação Estadual de Proteção Ambiental do Rio Grande do Sul, das quais 82% utilizam Roundup (original e transorb), que tem como princípio ativo o glifosato. O objetivo deste trabalho foi analisar o impacto ambiental da atividade agrícola na REBIO Mato Grande por meio de marcadores de poluentes no ambiente e a comunidade de macroinvertebrados bentônicos em três pontos do Arroio Moreira, por ser o que mais contribui com volume hídrico. O indicador de lançamento de efluentes domésticos (alquilbenzeno linear sulfonado) não foi encontrado nas estações de coleta analisadas, o que mostra que os impactos sobre a fauna aquática não possuem contribuição significativa de atividades domésticas. Por outro lado, o marcador de atividade agrícola glifosato foi encontrado em um dos pontos (0,08 mg.L−1), estando acima do valor máximo permitido (0,065 mg.L−1) pela Resolução do Conselho Nacional do Meio Ambiente (CONAMA) nº 357/2005. Ocorreu diminuição em todas as métricas biológicas analisadas (riqueza, índice de diversidade de Shannon-Wiener e abundância) e alterações dos parâmetros abióticos como oxigênio dissolvido, condutividade, turbidez e sólidos totais dissolvidos. Permitindo concluir que a orizicultura contribui significativamente para a perturbação do ambiente analisado.

ABSTRACT: The Biological Reserve (REBIO) of Mato Grande is a Conservation Unit located in the municipality of Arroio Grande, in the south of Rio Grande do Sul. Its amortization zone has forty rural properties registered in the irrigation system of the State Foundation for Environmental Protection of RS (FEPAM), of which about 82%, use Roundup (original and transorb) whose active ingredient is glyphosate. The objective of this work was to analyze the environmental impact of rice growing in REBIO Mato Grande through pollutant markers in the environment and the benthic macroinvertebrate community in three points of the Arroio Moreira, as it is the one that most contributes to water volume. The indicator for the release of domestic effluents (linear sulfonated alkylbenzene – LAS) was not found in the collection stations analyzed, indicating that the impacts on aquatic fauna do not have a significant contribution from domestic activities. On the other hand, the glyphosate agricultural activity marker was found at one of the points (0.08 mg.L−1) being above the maximum allowed value (0.065 mg.L−1) by CONAMA Resolution No. 357/2005. There was a decrease in all biological metrics analyzed (Wealth, Shannon-Wiener diversity index and Abundance) and changes in abiotic parameters such as dissolved oxygen, conductivity, turbidity, and total dissolved solids, allowing us to conclude that rice farming contributes significantly to the disturbance of the analyzed environment.