ECOLOGICAL ASSESSMENT AND WATER QUALITY USING BENTHIC DIATOM COMMUNITIES IN AN ECUADORIAN AMAZON RIVERLuis Quevedo, Karla Merino, Sofia Godoy and Cumanda CarreraAbstract This work determined the water quality and ecological status of a stretch of the RÃo Blanco river becoming probably in the first approach to the study of benthic diatom communities inhabiting this small Amazon river of Ecuador. Surveys conducted in a study area with a length of 3 km and an altitudinal gradient of 500 meters were analyzed. Descriptive community parameters (Richness (S), Pielouâs evenness index (Jâ) and Margalef richness index (d)) were calculated, and water quality was estimated by the Specific Polluosensitivity Index (IPS). Even when there is the presence of punctual anthropogenic activities, we found a good quality of water which could be attributable to the geomorphologic and climatic characteristics of the zone where the altitude gradient allows permanent oxygenation of the water, and it is possible to evidence high volumes of precipitation and flow. |