EVALUATION OF THE ECOLOGICAL STATE USING THE WATER QUALITY INDEX AND FLUVIAL HABITAT INDEX OF THE URBAN BASINS OF PANAMA

Abstract

The evaluation of the ecological status of aquatic ecosystems through indices allows quantifying and assessing the environmental impacts caused by human activities, in order to create a baseline for future adjustments in policies regarding environmental management, both at the level of local governments as nationals, who can collaborate in a better management of water resources. This study was carried out in the urban basins of Panama City, a place with the highest population concentration in the country, specifically in the Matasnillo, Juan Díaz and Pacora Rivers, in order to assess the ecological status using the water quality index (WQI) and the river habitat index (FHI). With the data collected from the samples in the high, medium and low zones, a Kruskall–Wallis Test was applied to determine if there were significant differences between the sampling points and in the season’s characteristics of the tropical climate, the humid and dry, plus a sampling in and transition between both seasons. The results show us that the rivers maintain better conditions in remote areas or with less human impact, indicating that the upper areas of the Matasnillo, Juan Díaz and Pacora Rivers have the best scores in the WQI and FHI, decreasing their score in the middle and lower zones. The low WQI and FHI scores indicate the environmental impact caused by alterations to habitats due to canalization or construction of civil structures that end up modifying the hydrology, reducing the heterogeneity of habitats and the type of substrate, in addition to inadequate waste management, solids and liquids from human settlements, commercial and industrial activities, as well as agricultural areas in the rural perimeter that as a whole exert pressure on these urban basins as they pass.