CHANGES IN FLOW REGIME AND ITS IMPACTS ON THE QUALITATIVE AND QUANTITATIVE ASPECTS OF FISH FAUNA OF RIVER TAWI IN THE VICINITY OF JAMMU CITY

Prof. K. K. Sharma, Dr. Sarbjeet Kour, Dr. Shvetambri, Neha Sharma*

ABSTRACT

Many studies have assessed the effects of large dams on fishes but a few have examined the effects of small obstacles like weirs and barrages. Fish diversity was sampled and environmental variables were characterized at four sites in river Tawi flowing through the heart of Jammu city. A total of four stations were selected, out of which two stations were upstream the ongoing construction of the barrage, one on the site of barrage and one downstream the barrage. The continuous changing of flow regime of river due to ongoing construction of barrage, physical disturbances on the construction site due to heavy machinery and concrete, pollution due to entrance of sewage canals prior to and very near the barrage site, changes in water volume and course in different seasons, indiscriminate fishing and river being notorious for flash floods are also the major contributors to the difference in fish fauna distribution in the river. The reference river exhibited a longitudinal gradient of various physicochemical characteristics but these weren’t the only reasons for significant differences in the fish assemblage composition and structure. The continuous changing of flow regime of river due to ongoing construction of barrage, physical disturbances on the construction site due to heavy machinery and concrete, pollution due to entrance of sewage canals prior to and very near the barrage site, changes in water volume and course in different seasons, indiscriminate fishing and river being notorious for flash floods. Studies were carried out in four stations of river Tawi and results were expressed in terms of qualitative and quantitative distribution of fish fauna in the river stretch in the vicinity of Jammu city.

Keywords: barrage, upstream, indiscriminate, flow regime.