The Impact of Floating Net Cage (FNC) on Primary Productivity in Cirata Reservoir Waters

Abstract

Cirata Reservoir is one of the three cascade reservoirs fed by the Citarum Watershed with an area of ​​62 km2 (6.200 ha) and has a water volume of 1.900 million m3. The great potential of the waters in the Cirata Reservoir is utilized by the local community as a source of livelihood, namely by conducting aquaculture activities using floating net cages (FNC) in excess. FNC is thought to be a source of waste that reduces reservoir water quality. This research aims to determine the impact of FNC cultivation on primary productivity with different FNC densities at each station. The research was conducted in Cianjur Regency by taking on three stations, namely in the areas of Jangari, Maleber, and Patok Beusi on November 6 - December 8, 2019. The method used in the research was purposive sampling then analyzed in detail and quantitatively. The results show that reservoir waters have an average of physical parameters, namely temperature 32.2-32.6oC, transparency 0.59-0.68 meters, pH 7.1-7.3, carbon dioxide 15.4-16.1 mg / l, Dissolved Oxygen 6.9-7.3 mg / l, Biochemical Oxygen Demand 6.1-7.8 mg / l, nitrate 0.208-0.222 mg / l, ammonia 0.002833-0.003056 mg / l, phosphate 0,165-0,167 mg / l and primary productivity 240,36-277,90 mgC/m3/hour. This shows that the water indicator is still classified as good because it does not exceed the water quality standard.