Primary Productivity of Blanakan Fishpond at Subang, West Java

Abstract

Subang regency is one of the largest fisheries area in West Java, so it is important to maintain the quality of fishpond area in Blanakan, Subang. Primary productivity can be defined as the production rate of organic carbon per unit time which is the result of solar energy by green plants to be converted into chemical energy through photosynthesis. Primary productivity can be used to define the quality of an ecosystem including fishpond. The aim of this research was to measure the value of primary productivity in mangrove fishpond, determine the correlation between the primary productivity and the content of nitrate, phosphate, and chlorophyll-a, and to analyse the significance primary productivity differences among three sampling stations. The samples were collected from three sampling stations, where all of those consist of mangrove Avicennia marina vegetation. Each station was divided into two points based on different depth i.e. 0 and 1,5 meters. The measurement of primary productivity was done by light-dark bottle method, meanwhile the nitrate, phosphate and chlorophyll-a concentration by spectrophotometer method. The result showed that the value of primary productivity ranged from 39.0625 to 101.5625 mgC/m3/day with the highest value obtained at station I and the lowest value at station III. According to statistical test, there were a significant differences of primary productivity value among three sampling stations with the value is 0.003 (p < 0.05). Correlation analysis showed that primary productivity was correlated positively with chloropyll-a and negatively with nitrate and phosphate contain water.