Factors affecting the ecological habitat of Benthic macro-invertebrate assemblages in Asan wetland, Dehradun in Garhwal Himalaya

Abstract

The Himalayan region has several freshwater resources, such as rivers, lakes, and wetlands. These freshwater resources have been adversely affected by environmental factors. Freshwater biological systems are defenseless against outcomes of environmental changes that might prompt the irreversible disintegration of these natural surroundings. The present study aimed to investigate the effect of biotic and abiotic factors on the Benthic macro-invertebrate assemblages of the Asan wetland, Dehradun in Garhwal Himalaya. A determination of the physico-chemical health status of the Asan wetland viz., electrical conductivity (EC), total dissolved solids (TDS), biochemical oxygen demand (BOD), and nutrients parameters like nitrogen, potassium, and phosphorus were investigated during this study. Three sampling sites (Site 1, Site 2 and Site 3) of wetland were selected and the water samples were collected seasonally, i.e., summer, winter, and monsoon from April 2021-March 2022. Maximum values of EC(163.75 µS/cm), TDS (232.78 (mg/l), alkalinity (141.20 mg/l) and pH(7.8) were recorded in the monsoon season (June-September) and minimum values of EC( 135.80µS/cm), TDS (196.80 (mg/l), alkalinity (119.80mg/l) and pH(7.2) were recorded in the winter season (November–February). An overall total of 18 macrobenthos genera belonging to four classes was identified. Maximum communities of macrobenthos were observed during the winter and minimum communities during the monsoon season. Canonical correspondence analysis (CCA) was used to determine whether microbenthic genera and habitat ecological parameters and showed a positive or negative correlation. Thus, the present study contributed to the status of various factors and their impacts on the Benthic macro-invertebrate structure of the Asan wetland.