UTTAR PRADESH JOURNAL OF ZOOLOGY

The present study was carried out to find the changes in physical-chemical parameters in potential fishing zones (PFZs) and Non potential fishing zones (N-PFZ) in three different sites including Dabhol, Harnai and Mirkarwada of Ratnagiri district Maharashtra. The various parameters like Water temperature, Turbidity, Total solid (TS), Total dissolved solids (TDS), PH, Dissolve oxygen, Biochemical oxygen demand, Chemical oxygen demand (COD), Free Carbon dioxide, Total alkalinity, Hardness, Total acidity, Chloride, Phosphate-Phosphorous (PO4-P), Nitrate-Nitrogen(N02-N). The minimum and maximum values  Water temperature were- 25.12-30.9 (C),  Turbidity- 1.87-4.15 (NTU), Total solid- 32728.47-37229.12 (mg/L), Total dissolved solid- 32108.66-36690.56 (mg/L), PH- 7.54-8.69, Dissolve oxygen-4.58-7.09 (mg/L), Biological oxygen demand-1.02-2.06 (mg/L), Chemical oxygen demand-2.18-3.41 (mg/L), Free carbon dioxide- 1.66-3.48 (mg/L), Alkalinity-133.43-166.95(mg/L), Hardness- 6043.21-7108.44 (mg/L), Acidity-0.04-0.14 (mg/L),  Chloride-18051.6-20955.09 (mg/L), Phosphate-Phosphorous- 0.04-0.08 (mg/L), Nitrate-Nitrogen (NO2-N)-0.02-0.06 (mg/L).The observed data in the Dabhol, Harnai, and Mirkarwada PFZ and N-PFZ zones show dynamic seasonal changes driven by temperature, runoff, biological activity, and monsoon cycles. The designation of PFZs as rich fishing grounds was supported by their persistent higher biological activity, which was demonstrated by increased levels of BOD, turbidity, phosphate, and nitrite.