Ecological health assessment through water quality and elemental analysis of Asola Bhatti Wildlife Sanctuary

Abstract

In protected areas, water resources are essential for maintaining ecosystem functions, wildlife habitats, and biodiversity. The current study was carried out at Asola Bhatti Wildlife Sanctuary, one of the few protected areas in the Delhi region. Physical, chemical, and heavy metal analyses were performed on pond, lake, and groundwater samples. ICP MS identified heavy metals (As, Cd, Zn, Ni, Fe, Cr, Cu, and Pb) and physicochemical parameters (pH, EC, TDS, nitrate, sulphate, phosphorus, COD, alkalinity, turbidity, hardness, chloride, and fluoride). Except for phosphate, TDS, Cr, and Cd, all parameters were within limits. The overall water quality WQI for each location ranged from 8.72 to 93.24 using WAWQI. The pond sample (S5 < S6 < S7) has been identified of having low water quality due to solid and sewage waste disposal. S6 and S7 sampling locations had HMI values of 1173 and 11478, indicating heavy metal pollution in the water bodies. However, the S5 site (93.25) suggests against surpassing 100 HMI. TDS correlated positively with phosphate (0.61), nitrate (0.64), alkalinity (0.79), and EC (0.92). Fluoride negatively correlates with EC (r = -0.86), TDS (r = -0.82), nitrate (r = -0.67), and alkalinity (r = -0.70) at the p < 0.05 level. The WQI and HMI indicate that urbanisation, encroachment, solid waste dumping, and sewage and residential drainage have contaminated many ABWS waters. Water quality has also declined due to precipitation, soil erosion, weathering, and mineral dissolution. Therefore, the overall results of the water quality assessment are very important and provide guidance for creating and implementing effective management plans to support the region's sustainable and comprehensive development.