STUDY OF THE PLANKTONIC COMMUNITY, FECUNDITY AND LENGTH WEIGHT RELATIONSHIP FROM THE BAIGUL RESERVOIR OF DISTRICT UDHAM SINGH NAGAR, UTTARAKHAND

摘要

The fish productivity from the reservoir in its all naturalness depends on various abiotic and biotic factors. The abiotic factors include mostly all physico-chemical parameters of water body, which have immense influence on biogenic factors and existence of flora and fauna in the reservoir. The first and foremost impact of physico-chemical parameters are experienced by the biotic community existing at the base of trophic level, which include the autotrophs like phytoplankton, which forms the very basic source of food material for the first order consumers like fishes who thrive on the pasture of phytoplankton. The physical factors like insolation, temperature, transparency had the direct impact on the existence of phytoplankton.The results obtained clearly indicates the existence of high bloom of plankton in the summer months owing to increased availability of radiant sun’s energy (insolation), rise in temperature and high level of transparency accounting for the enhanced photosynthetic activity. The astonishingly high bloom phytoplankton at all the stations of the recording in the summer ensured the ample availability of food material for pelagic fishes.The length-weight measurement conducted for all the fishes from the reservoir evidently indicated the maximum gain of the growth of fishes during the summer months. The community, which derived the maximum advantage of high intensity of feeding on phytoplankton during the summer months resulting into enhanced growth, was mostly the carps (Indian major carps and minor carps) from the reservoir. The correlation of finding of fish fecundity in the reservoir to the conversion eggs into spawns at the rate nf minimum 50%, it was estimated that there was addition of average number of over 20.0 Lakh from Catla catla-, over 30.0 Lakh from Labeo rohita, over 20.0 Lakh of Cirrhinus mrigala, over 15.0 Lakh from Heteropneustes fossilis and Channa striatus, over 35.0 Lakh Labeo gonius.