Environmental conditions of some paddy cum prawn culture fields of Cochin backwaters, southwest coast of India

Abstract

Temperature, salinity, pH, dissolved oxygen, inorganic phosphate, ammonia, nitrate and nitrite of seasonal and perennial prawn culture fields from 3 areas of Cochin backwaters are studied. Area 1 is a region least affected ecologically and the salinity values 10 x 10-3 occur here during December to June. Area 2 which is near to the location of effluent discharge from a fertiliser factory shows high concentration of nutrients with low prawn production. Area 3 is most favourably situated to resist ecological distortions because of its proximity to the sea. The results indicate that the fields in areas 1 and 3 have environmental conditions highly suited for prawn culture whereas in area 2 the salinity conditions are not very conducive for prawn growth