Hydrochemical Profile of Pariyej Community Reservoir (PCR), Gujarat, India: A Multivariate Statistical Approach using Multidimensional Scaling

The present study was undertaken at Pariyej Community Reservoir (PCR), Gujarat, India; a freshwater inland wetland of national importance; listed in Asian Directory of Wetlands. The aim of this biannual research was to monitor the seasonal alterations in hydrochemical characteristics along the six monthly gradients (April to September, 2021; Summer, Monsoon, Post-Monsoon) at three (PCR-1, 2, 3) pre-fixed transactional stations of PCR. The surface water quality of freshwater inland wetland was assessed using 21 hydrochemical parameters e.g. physical variables (Temperature, EC, TS, TSS, TDS, Turbidity), chemical variables (pH, DO, Acidity, Free CO2, PA, TA, Carbonates, Bicarbonates, Chloride, Total Hardness, Ca Hardness, Mg Hardness, and nutrients variables (Sulphate, Phosphate, Nitrate). The surface water of PCR-1 exhibited accentuated amount of TDS, pH, Phosphate and Sulphate; PCR-2 with TS, TSS, DO, Acidity and Free CO2, and PCR-3 with Temperature, EC, Turbidity, TA, Bicarbonates, Chloride, Total Hardness, Ca Hardness, Mg Hardness and Sulphate. Principal Component Analysis (PCA) revealed positive loading between EC (0.759), TS (3.276), TSS (2.244), TDS (0.452) and Total Hardness (0.114) in PCR-1; PCR-2 with EC (1.006), TS (0.739), TDS (3.141), TA (0.020), Bicarbonates (0.020), Total Hardness (0.599), Ca Hardness (0.167) and Mg Hardness (0.166), and PCR-3 with EC (3.229), Acidity (0.383), TA (0.395), Bicarbonates (0.395), Chloride (0.329), Total Hardness (1.483) and Ca Hardness (1.131). Among them, significant gradient was found in TS (3.276), TSS (2.244) at PCR-1, EC (1.006), TDS (3.141) at PCR-2, and EC (3.229), Total Hardness (1.483) and Ca Hardness (1.131) at PCR-3. In addition, univariate analysis revealed the peak pollution load at PCR-2 (161.96), followed by moderate pollution load at PCR-3 (157.03) and the lowest pollution load was observed at PCR-1 (150.45). Moreover, the outcomes of the present study revealed that hydrochemical variables were more fluctuated at PCR-2 (290.63), followed by modest variation of physico-chemical constituents at PCR-1 (260.02) and the minimal oscillation of surface water elements at PCR-3 (259.15). The above fallouts might be due to prolific, lush and uncontrolled growth of aquatic vegetation e.g. Typha angustata at PCR-2, profuse span of Nelumbo nucifera and meager subsistence of Phragmitis australis at PCR-3. The findings of the present study signifies the importance of PCR as a freshwater inland wetland of national importance in terms of sustainability and sanctity of surface water quality as it provides incessant water supply to around 800 villages of the Main Saurashtra Land. This baseline study on wetland monitoring, hydrological regimes, aquatic pollution and environmental sustainability will be helpful to ecologists, environmentalists and biologists to conserve, protect and manage the prevailing freshwater wetland ecosystems of Gujarat, India.