Increased Oscillatoria sp. Population on Integrated Cultivation Ponds of Rice and Tiger Shrimp (Penaeus monodon) in Idle Land

Tiger shrimp culture that is maintained integrated with rice on idle land because of sea water intrusion has been tested in 2018 through the Innovative Adaptive Technology of Brackish Fisheries (INTAN-AP) pioneering from the Fisheries Research Center of the Human Resources Research Agency. There were 5 pond of rice fields used in the experiment in July-December 2018 in Oring Countryside, Lawallu Village, Barru Regency, South Sulawesi. Rice seeds of INPARI 34 and 35 varieties were kept in the paddy fields and PL 45 tiger shrimp were cultivated in the caren field, while re-fertilization was carried out using N, P, K fertilizers while shrimp were given commercial feed during cultivation based on weight gain per sampling. Plankton sampling was carried out in tiger shrimp ricecultivated land, every 7 days using plankton net mesh size No. 25, and then analyzed at the plankton laboratory in Research Institute for Coastal Aquaculture and Fisheries Extension in Maros. Then the data is calculated the abundance of the population then discussed descriptively. The results found that the population of Oscillatoria sp phytoplankton increases every time they conduct sampling until it reaches the peak of its population, along with the period of fertilizer application and the increase in the amount of feed given to tiger shrimp. The highest population peak at the 7th sampling in the pond 5 was 25,316 cells / L and in the pond 4 when the 6th sampling was 22,300 cells / L.