Ecological River Water Quality Based on Macroinvertebrates Present in the Ecuadorian Amazon

The Yanaquincha River is one of the tributaries that crosses the canton of La Joya de los Sachas from north to south, where the increase in human activities is affecting the quality of water used for agricultural activities and in tourist resorts. The purpose of this research was to determine the biological quality of the water through the BMWP-Col index and physicochemical parameters. Five sampling sites were selected along the length of the river for this assessment. Relatively intact sites were classified as reference sites (BR and FR), moderately impacted sites (EPC and EFPC), and severely impacted sites (PC). Biological and physicochemical data were collected to examine the quality of the water. The Biological Monitoring Working Party Colombia (BMWP-Col) biotic index and Functional Feeding Group (FFG) grouping were used to evaluate river quality. The results showed that water temperature, depth, width, and turbidity are important parameters in the composition of families. In the sampling sites, the BMWP-Col index was a determinant for river water quality (moderate, poor, or bad). Good quality water was not found in any of the sampling sites. The composition of the macroinvertebrate community changes from the source of the river until it ends its journey in the city. In addition, the family abundance and the composition of the feeding group were observed in the sites that showed similar or the same quality of water. The diversity of families and FFGs was generally higher at sites of moderate water quality. Chironomidae and Annelida were the most abundant families while Leptoceridae was the least abundant. The diversity of families was higher in BR while it was lower in PC and EFPC, grouped in six and four (both PC and EFPC) FFGs, respectively. It is important to carry out this type of study in the Ecuadorian Amazon because there is a lack of knowledge about taxonomic and functional diversity and the physicochemical variables with water quality.