ON THE WATER QUALITY OF FISH PONDS AND THEIR SUITABILITY FOR FISH PRODUCTION IN WEST GODAVARI AND KRISHNA DISTRICTS OF ANDHRA PRADESH, INDIA

摘要

The paper deals with the physico-chemical parameters of water in fish ponds of west Godavari and Krishna districts of Andhra Pradesh for a period of one year- 2008-'09. In the present investigation, the following observations were noticed. The water temperature is low (25.2℃) during January and high (34.2℃) during May in west Godavari whereas in Krishna the lowest was 25℃ (February) and 33.3℃ (May). The sechhi disc turbidity was also varying from 0.22m (October) to 0.35m (August) in West Godavari (pond 1) the same in Krishna (pond2) ranges from 0.23 m (December) to 0.40 m (June). The dissolved oxygen ranges from 2.9 mg/L (July) to 5.21 mg/L (Mar) and 3.32 mg/ L (Apr) to 5.8 mg/L (July and Sept) in pond 1 and 2 respectively. The pH levels of West Godavari district ranges from 7.36 (Feb) to 8.8 (Jan) whereas the pH levels of Krishna district ranges from 7.85 (Feb) to 8.7(Sept). The hardness levels ranges from 148 ppm (Aug) to 305 ppm (Dec) in pond 1 and ranges from 178 ppm (Feb) to 340 ppm (Nov) in pond 2. Alkalinity levels of West Godavari district ranges from 198 ppm (Jan) to 312 ppm (Jul) whereas the Alkalinity levels of Krishna district ranges from 172 ppm (Apr) to 310 ppm (Aug). The Ammonia, Nitrite and Nitrate in pond 1 were 0.47±0.35 μm, 0.027±0.01 μm, 1.89 +0.57 μm respectively whereas the same variables in pond2 are 0.31±0.2 μm, 2,l7±0.82 (μm, 1.89±0.57 μm respectively.