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El estudio y desarrollo de las leyes ambientales que sistematizan el manejo de los cuerpos hídricos requiere la identificación de bioindicadores ara establecer su estado ecológico, es así que el presente estudio tiene como objetivo determinar la diversidad de macroinvertebrados como bioindicadores de la calidad del agua del río Yuquipa. Se estudiaron tres estaciones de monitoreo en los meses de noviembre y diciembre de 2020 y enero de 2021, en cada estación se recolectaron las especies de macroinvertebrados, el índice de Shannon se encargó de medir la diversidad de especies el cual expresa la uniformidad de los valores de importancia a través de todas las especies, en la determinación de la calidad del agua se utilizó el índice biótico de familia que asigna diferentes valores de tolerancia y considera el nivel taxonómico. Se reconocieron dos grupos de sitios. El primer grupo PY-2 y PY-3 fue valorado como calidad del agua excelente (3.26 y 3.12) respectivamente, con una diversidad media (2.45 y 2.54), mientras que en el sitio PY-1 fue valorado como calidad del agua regular (5.34) con una diversidad media de 2.36. Concluyendo que la diversidad y la calidad del agua no se han visto afectadas por las actividades antropogénicas. The study and development of environmental laws that systematize the management of water bodies requires the identification of bioindicators to establish their ecological status. Therefore, this study aims to determine the macroinvertebrates diversity as bioindicators of Yuquipa river water quality. Three monitoring stations were studied on November, December 2020 and on January 2021; macroinvertebrates species were gathered and the Shannon index was used to measure species diversity, which expresses the uniformity of importance values across all species. Furthermore, the family biotic index was used to determine the water quality, as it ascribes different tolerance values and considers the taxonomic level. Two location groups were recognised: the first PY-2 and PY-3 was rated as excellent water quality (3.26 and 3.12) respectively, with a mean diversity (2.45 and 2.54), while the PY-1 site was rated as regular water quality (5.34) with a mean diversity of 2.36. The result was that diversity and water quality were not affected by anthropogenic activities.

The study and development of environmental laws that systematize the management of water bodies requires the identification of bioindicators to establish their ecological status. Therefore, this study aims to determine the macroinvertebrates diversity as bioindicators of Yuquipa river water quality. Three monitoring stations were studied on November, December 2020 and on January 2021; macroinvertebrates species were gathered and the Shannon index was used to measure species diversity, which expresses the uniformity of importance values across all species. Furthermore, the family biotic index was used to determine the water quality, as it ascribes different tolerance values and considers the taxonomic level. Two location groups were recognised: the first PY-2 and PY-3 was rated as excellent water quality (3.26 and 3.12) respectively, with a mean diversity (2.45 and 2.54), while the PY-1 site was rated as regular water quality (5.34) with a mean diversity of 2.36. The result was that diversity and water quality were not affected by anthropogenic activities. El estudio y desarrollo de las leyes ambientales que sistematizan el manejo de los cuerpos hídricos requiere la identificación de bioindicadores ara establecer su estado ecológico, es así que el presente estudio tiene como objetivo determinar la diversidad de macroinvertebrados como bioindicadores de la calidad del agua del río Yuquipa. Se estudiaron tres estaciones de monitoreo en los meses de noviembre y diciembre de 2020 y enero de 2021, en cada estación se recolectaron las especies de macroinvertebrados, el índice de Shannon se encargó de medir la diversidad de especies el cual expresa la uniformidad de los valores de importancia a través de todas las especies, en la determinación de la calidad del agua se utilizó el índice biótico de familia que asigna diferentes valores de tolerancia y considera el nivel taxonómico. Se reconocieron dos grupos de sitios. El primer grupo PY-2 y PY-3 fue valorado como calidad del agua excelente (3.26 y 3.12) respectivamente, con una diversidad media (2.45 y 2.54), mientras que en el sitio PY-1 fue valorado como calidad del agua regular (5.34) con una diversidad media de 2.36. Concluyendo que la diversidad y la calidad del agua no se han visto afectadas por las actividades antropogénicas.

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.

The importance of standing water habitat for amphibians is widely known and recognized. However, in some arid or semiarid zones the availability of these temporal habitats is uncertain and fluvial habitats could play a very important role for amphibian conservation. For example, in the Mediterranean region many fluvial habitats have a temporary character, lacking predatory fish populations and hosting diverse amphibian communities. To compare the relative importance of various fluvial and still water habitats, we studied the breeding amphibian community over a wide area from 2006 to 2008 in southwestern Spain. All amphibian species found in the area were present in lotic habitats and the highest amphibian diversity was found in temporary stream habitats. Fluvial habitats were among the most important habitats used for reproduction by eight amphibian species of conservation concern, whereas for seven species a significant positive selection was found towards one or several fluvial habitat types as reproduction habitats. The conservation of fluvial habitats including rigorous impact assessments and management programs can be very important for the conservation of endangered amphibians in these semi-arid areas.

[ES] La modelización numérica del flujo de agua en ríos es una herramienta que ayuda a dar respuesta a la legislación vigente europea y española referida a riesgo de inundación. Los modelos numéricos disponibles actualmente se encuentran en constante evolución. Mientras hace una década la modelización unidimensional era prácticamente la única alternativa, en el presente se han generalizado los modelos bidimensionales y se empiezan a utilizar los tridimensionales. Gracias a las actuales herramientas SIG, los resultados de la modelización numérica se pueden combinar con datos georreferenciados para realizar una cuantificación sistemática del riesgo de inundación. En este proceso existen aún una serie de desafíos como la consideración de los caudales sólidos y sus efectos en la morfología del cauce, una correcta descripción del flujo en puentes y estructuras, la integración de modelos hidrológicos con los modelos hidráulicos para una mejor consideración de las condiciones de contorno, y finalmente la optimización de las herramientas para disminuir los tiempos de cálculo actuales., [EN] At the present time there is a strong demand from policy makers for reliable predictions of the effects of climate and land use changes on inundation risk, in order to meet the targets specified in the EU Water Framework Directive. Numerical models are a valuable predictive tool to support decision-making related to the implementation of water and flood risk management strategies. While a decade ago one-dimensional modelling was the most commonly used tool in inundation studies, at the present time the application of two-dimensional models to river inundation modelling is generalized. Combined with GIS tools, the water depth and velocity results of a 2D model can be efficiently combined with land use data in order to quantify the potential damages caused by a certain inundation. Nevertheless, in order to improve the reliability of the numerical predictions, a number of challenges should be addressed in current models, as: modelling the interaction between hydrodynamics, solid loads, and morphologic changes during extreme flood events; a correct characterisation of head losses and flow through bridges with complex geometries; the integration of hydrological and hydraulic models for a better consideration of boundary conditions; and the implementation of efficient parallelization techniques in order to reduce the computational time and increase the scale of the problems which can be addressed with 2D and 3D models.

En enero de 2006 se estudiaron los patrones espaciales de distribución de comunidades de macroinvertebrados bentónicos de la cuenca hidrográfica del río Baker (45°50' O y 47°55' S) y los principales factores controladores, intentando cubrir la mayor variedad de ecosistemas lóticos. Para llevar a cabo el estudio se seleccionaron 27 estaciones de muestreo ubicadas en las diferentes subcuencas del río. En cada estación se realizó una caracterización fisicoquímica del agua (conductividad, oxígeno disuelto, pH, temperatura y turbidez), y se documentaron las características del tramo de río (e.g. ancho del cauce y tipo de sedimento) e información cartográfica utilizando un sistema de información geográfica (SIG). Se identificaron un total de 51 taxa que correspondieron en su mayoría a larvas de insectos (80 %). Los grupos con mayor riqueza fueron los órdenes Ephemeroptera (15 taxa), Plecoptera (8 taxa) y Trichoptera (8 taxa). Los análisis de clasificación y ordenación realizados con los datos de abundancia, permitieron reconocer siete grupos de estaciones diferentes (A-F) que fueron estadísticamente significativos (P < 0.05). El análisis de regresión múltiple, muestra que la variable ambiental que mejor explica los patrones biológicos observados, fue el porcentaje de cobertura de bolones, explicando el 44 % de la varianza de los datos biológicos (r² = 0.44 P < 0.05). In January of 2006 we studied the distributional patterns of benthic macroinvertebrate communities of the Baker river basin (45°50' O and 47°55' S) and their main controlling factors trying to cover the greater variety of the lotic ecosystems. To carry out the study, 27 sampling stations were located in the different sub basins of the river. In each station, physical-chemical parameters of the column of water were quantified (conductivity, dissolved oxygen, pH, temperature and turbidity), and documented characteristics of the segment (e.g. wide of the channel and sediment type) and cartographic information using a geographic information system (GIS) and complemented with cartographic information using GIS. Identified a total of 51 taxa, are mostly insect larvae (80 %). The groups most richness were orders Ephemeroptera (15 taxa), Plecoptera (8 taxa) and Trichoptera (8 taxa). The classification and ordination analyses carried out with the data of abundance, allowed to recognize seven groups stations (A-F) statistically significant (P < 0.05). The múltiple regression analysis, showed that the environmental variable that accounts for the observed biological patterns, was coverage cobble, explaining 45.1 % the variance of the biological data (r² = 0.44 P < 0.05).

Se estudiaron las comunidades de macroinvertebrados bentónicos de la cuenca hidrográfica del río Aysén (44°45' -46°15'S; 71°00' - 73°00'W). Semuestreó en 14 estaciones que se distribuyeron en las diferentes subcuencas intentado cubrir la mayor variabilidad del paisaje fluvial. Los muéstreos de macroinvertebrados se realizaron empleando una red Surber. En cada sitio se cuantificaron parámetros fisico-químicos de la columna de agua (pH, conductividad eléctrica, sólidos disueltos, temperatura y oxígeno disuelto), además de parámetros físicos del río (orden del río, pendiente, ancho, profundidad media, velocidad media, tipología de la vegetación ribereña y substrato). Se identificó un total de 59 taxa, la mayor parte de los cuales correspondió a estados inmaduros de insectos (83%). Dentro de éstos, los grupos más diversos fueron los órdenes Plecoptera (19 taxa), Ephemeroptera (14 taxa) y Trichoptera (10 taxa). Los análisis de clasificación y ordenación de estaciones realizados con los datos de abundancia, permitieron reconocer cinco grupos de estaciones estadísticamente diferenciados (P

In recent years the need to restore impacted habitats has become a fundamental aspect of environmental management in order to match sustainable development requirements. This is particularly important for fluvial habitats because of their role in the landscapes as environmental corridors. For these reasons the correct management of the restoration ecology interventions is mandatory and the ecosystem characteristics, as well as the influence of its landscape, have to be taken into account. In order to correctly realize buffer strip intervention, one of the most used restoration techniques, we propose an approach which uses field measurements for fluvial functionality and satellite data integrated with hydrological models to obtain information on the landscape influence on the river system. The investigation involved the high valley of the Agri River located in the Basilicata region, Southern Italy. The first step to the analysis involves the investigation of the fluvial ecosystem quality by using the Italian IFF Index (Fluvial Functionality Index), which differentiates various river segments in different levels of functionality. Meanwhile, by using a multispectral satellite image (LANDSAT TM 5) a land use map of the area of interest was performed. This land use map represented an important input for the hydrological simulation, which identified fluvial segments receiving the highest amount of landscape surface runoff, which is the most important cause of pollutant transporting from surrounding areas. All the results have been recorded and integrated in a Geographical Information System to define the final prediction for the localization of the buffer strips. The results obtained underline that the identification of the intervention sites realized by using the IFF field measurements and satellite-based hydrological analyses are complementary since critical segments respectively identified are not completely overlapped. Therefore, an integrated approach is fundamental to better plan the management of restoration ecology interventions.