Epilithic diatom communities are particularly suitable for the evaluation of freshwater quality. In Ecuador, however, no water quality index includes this biotic parameter. This work is the first attempt in the country to determine the composition of epilithic diatom communities associated with different degrees of eutrophication. This was accomplished by measuring physical, chemical and microbiological variables at five sampling sites along the Pita River, Ecuador, from August to December 2016. The results indicate a clear gradient of eutrophication from sampling sites P1 (good water) in the upper reaches to P5 (bad water) located in the lower reaches. Concerning diatom analyses, the results indicated a high diversity for tropical areas in terms of species richness, varying from S=34 in headwaters to S=42 downstream. Moreover, the results obtained suggest a lack of concordance with the trophic values given to some of the epilithic diatoms in the literature. There were also species that seem to be sensitive to downstream nutrient increases that were not considered as bioindicators in previous studies. We concluded that the trophic values of diatom species available in the scientific literature are not directly applicable to their sites in the Pita River. Hence, it is necessary to establish a trophic diatom index for the Andean region of Ecuador.

This research represents a study in an Amazonian village that has similar structures to others Kichwa Amazonian villages of Ecuador. We evaluated the diversity, ecology, possibility of mosquitoes/ pathogens translocation from forest to urban area, and the vulnerability by potential mosquito vectors of diseases through an intensive and fast method done January 2017. Our analyses registered a high diversity of mosquitos in Limoncocha village (33 spp, H’ 2.76), which includes four new records of species for Ecuador. We propose the biological reserve and the lagoon are determinant environmental factors for the high mosquito diversity, plus the socio-economic characteristics related with a deficient water pipeline supply and lack of solid waste system. Furthermore, the high diversity of sylvan mosquitoes registered throughout the area, that include several potential vectors, suggest a moderate to high vulnerability for the transference of pathogens from the Biological Reserve to the urbanized area, which may increase the circulation of little-known arboviruses (Mayaro, Ilheus, St Louis encephalitis) across Ecuador.

RESUMENEl agua subterránea es una de las principales fuentes de abastecimiento para los habitantes de las parroquias de Limoncocha y de Pompeya, ubicadas en la Amazonía ecuatoriana donde, además, se encuentra la Reserva Biológica Limoncocha (RBL) y su área de influencia (AI), cuyo ecosistema subterráneo recibe un aporte de agua proveniente de flujos externos a su límite. Tradicionalmente, el agua subterránea ha sido considerada protegida por el subsuelo, sin embargo, la disposición de contaminantes estables en zonas de infiltración favorable, podría causar que este recurso se contamine, poniendo en riesgo la salud de la población y la sostenibilidad de la reserva. Por ello, se propuso evaluar el peligro de contaminación del agua subterránea de dicha reserva, a través de la superposición de un mapa de vulnerabilidad del acuífero aplicando el método GODS, con un inventario de cargas contaminantes usando el método POSH y en función a esto, priorizar medidas en la protección de este recurso. Se determinó que, en la mayor parte del área de estudio, no existe peligro de contaminación del agua subterránea, no obstante, también se encontraron zonas de moderado y alto peligro para las que se propusieron medidas para prevenir el deterioro de la calidad del agua subterránea.Palabras clave: acuíferos, agua subterránea, contaminación del agua subterránea, sistemas de información geográfica. Avaliação do risco à contaminação dos aquíferos da Reserva Biológica de Limoncocha, Amazônia Equatoriana RESUMOA água subterrânea é uma das principais fontes para o abastecimento dos habitantes das paróquias de Limoncocha e de Pompeya, localizadas na Amazônia equatoriana, onde se encontra a Reserva Biológica Limoncocha (RBL) e sua área de influência (AI), cujo ecossistema subterrâneo recebe uma oferta substancial de água afluente de fora do seu limite. Tradicionalmente, a água subterrânea tem sido considerada como "protegida" pelo subsolo. No entanto, a disposição de poluentes estáveis de atividades humanas em áreas favoráveis de 653 Evaluación del riesgo a la contaminación de los acuíferos … Rev. Ambient. Água vol. 12 n. 4 Taubaté -Jul. / Aug. 2017 infiltração poderia causar esta contaminação dos recursos, colocando em risco a saúde da população e a sustentabilidade da reserva. Assim, é proposto se avaliar o risco de contaminação das águas subterrâneas da RBL e AI, através da sobreposição de um mapa de vulnerabilidade do aquífero usando o método GODS com um inventário de carga poluente utilizando o método POSH e, dessa forma, priorizar medidas de proteção deste recurso. Verificou-se que, na maior parte da área de estudo, não há perigo de contaminação das águas subterrâneas, no entanto, foram encontradas áreas de risco moderado e elevado para as quais foram propostas medidas para evitar a deterioração da qualidade dos recursos hídricos subterrâneos.Palavras-chave: águas subterrâneas, aquíferos, contaminação das águas subterrâneas, sistemas de informação geográfica. ABSTRACTGroundwater is one of the main supply sources of the inhabitants of...

INTRODUCTION. Phytotelmata are a botanical group with water-impounding structures formed by non-aquatic plants, such as leaf axils, perforated internodes, stem holes or depressions, rot-holes in tree trunks or branches (tree-holes), flowers, open fruits, among others. These plants offer suitable conditions for aquatic or semi-aquatic animals, in particular arthropods. Immature mosquitoes (Diptera: Culicidae) are well represented among the inhabitants of phytotelmata. OBJECTIVE. Carry out a rapid assessment of the biodiversity of mosquitoes present in different land uses in the population and biological reserve of Limoncocha, to assess the vulnerability and risk of transmission of pathogens that cause emerging diseases. METHODS. Immature mosquitoes were collected in different phytotelmata including Ananas comosus leaf axils in a deforested area with small crops nearby of the Limoncocha Biological Reserve. RESULTS. Fourth instar larvae of Wyeomyia (Wyeomyia) medioalbipes Lutz were found in this plant to confirm their presence in the country and to the cultivated pineapples as phytotelmata in Ecuador. DISCUSSION AND CONCLUSIONS. This is the first report for Ecuador of Ananas comosus as phytotelmata and the associated mosquito species. Additionally, the presence of Wy. medioalpes in the country is confirmed. This information is added in the epidemiological evaluation of vulnerability and risk for the transmission of pathogens with a biogeographical and ecological vision.

In the ablation zone of glacier habitats, cryoconite holes are known to harbor diverse microbial communities, including unique diatom floras distinct from those of surrounding aquatic and terrestrial systems. Besides descriptive studies, little is known about the diversity of cryoconite diatoms and their response to environmental stressors, particularly in low-latitude glaciers. This paper documents an extremely diversified diatom community in Antisana Glacier (Ecuador), reporting 278 taxa found in 54 surface holes, although with low individual abundances. Contrary to our expectations, assemblage structure did not respond to water physical or chemical characteristics, nor to cryoconite hole morphology, but to elevation. We demonstrate that elevation is a driver of diatom assemblages. Both alpha diversity (measured as Fisher's index) and species richness (corrected for unequal sample sizes) correlated negatively with elevation, suggesting a replacement toward simplified, poorer communities along this gradient. The taxonomic composition also changed significantly, as revealed by multivariate statistics. In summary, cryoconite holes are sites of high taxonomic diversity composed of taxa that are allochthonous in origin.