Response of Freshwater Macroinvertebrate Communities to Various Anthropogenic Stressors in Lolab Streams- A Lotic System of the Indian Himalayan Region

Abstract

This study evaluated the response of freshwater macroinvertebrate communities to several human-induced stresses in a characteristic temperate region with amassed population and population-related pollution. With the help of macroinvertebrate species associated with physicochemical parameters and contaminants in dissolved fractions, we aimed to establish an efficient bioassay approach for evaluating the water quality in the lotic ecosystems of Lolab streams. From the mouth of streams, a rapid scanning method was utilized and physicochemical analysis was done by utilizing APHA,2005. The standard method was used for macroinvertebrate collection and various indices were calculated using software like PAST, and  Pearson correlation, CCA ,PCA were also calculated using PAST software. We discovered considerable differences in physicochemical parameters along a longitudinal gradient, with average mean values like air temperature (17.69℃), water temperature (13.2℃), pH (8.09) dissolved oxygen (7.38mg/L), free CO2(131.96mg/L), total hardness (159.46 mg/L), Ammonical nitrogen(175.6 µg/L), Total phosphorus(62.85 µg/L) with the highest values recorded in populated and largely agriculturally developed areas in the catchment. A total number of 27 taxa were recorded belonging to 8 families. Trichoptera accounted for 36% of the total abundance studied, while Diptera accounted for 26%. Ephemeroptera accounts for 16% of all species. The macroinvertebrates displayed preferences for particular abiotic parameters, highlighting their potential utility in future research as dependable ecological indicators, molded by a synergistic mix of anthropogenic influences and land use intensity.