The efficiency of Rhizophora apiculata on nitrogen and phosphorus reduction of shrimp culture effluent was designed using 3 mangrove initial biomass (160.3 ,122.4 and 82 .5 g /stem) and 3 effluent sources (seawater, water effluent from shrimp culture and Hoagland solution). The results indicated that R. apiculata cultured in different effluent sources had significant differences in nitrogen and phophorus uptake rates (p< 0.05). R. apiculata grown in Hoagland solution showed the highest uptake rate of nitrogen and phosphorus at 925.7 and 143.4 kg /ha/yr respectively, and had no significant difference among initial biomass (p > 0 .05). For shrimp culture effluent, R. apiculata uptake rate of nitrogen and phosphorus was 148.1 and 16.0 kg/ha /yr, respectively. R. apiculata grown only in seawater showed no uptake of either nitrogen or phosphorus, but some nitrogen and phosphorus was released from the system to the water. For mangrove production, R. apiculata cultured in different effluent sources had significant differences in biomass production (p< 0.05). R. apiculata grown in Hoagland solution showed that its production varied by initial biomass (160.3, 122.4 and 8 2.5 g/stem) at 20.9, 41.4 and 36.0 ton/ha/yr, respectively. Production of R. apiculata grown in shrimp culture effluent was 11.2 ton/ha/yr without any biomass effect. There was only a small gain in mangrove grow n in seawater, at 6.2 ton/ha/yr. Reduction of nitrogen and phosphorus from the effluent water was significantly correlated to mangrove production. The results indicate that shrimp farm effluent can be treated by R. apiculata. Comparison nitrogen and phosphorus uptake by plant, R. apiculata gave an efficiency of 90% when grown in Hoagland solution and 80 % when grown in shrimp culture effluent without any biomass effect.
