Assessment of the water quality of Talomo river : a biological approach

Abstract

Rivers are essential freshwater ecosystems that significantly support biodiversity and contribute to local and global economic productivity. This study assesses the water quality of Talomo River in Davao City using biotic indices such as the Biological Monitoring Working Party (BMWP) and Average Score per Taxon (ASPT) through the collection of aquatic macroinvertebrates. Two locations were surveyed, resulting in a combined total of 129 species: the upstream site included 114 distinct species, while the downstream site contained 15 distinct species. BMWP and ASPT revealed that the water quality in the upstream site was “acceptable” while the downstream is in “very critical” condition. Diversity indices (Shannon-Weiner, Equitability, Simpson's Dominance, and Reciprocal) were used to quantify species diversity, evenness, and dominance. Although the diversity ranges at the two locations are almost identical, the downstream site exhibits higher dominance and lower evenness than the upstream values. The results highlight the complex ecological interdependencies within the Talomo River, emphasizing the need for continuous research to assess the river's well-being and preserve biodiversity.