Water Quality Evaluation of Post-Tin Mining Ponds Tourism in Bangka Island Using Diatom as Bioindicator

Abstract

post tin mining pnd in Bangka ISland has been used as a tourism place, fishing, fish ponds, andagricultural areas that can reduce water. the purpose of this study is to evaluate the quality of water in the post-tin mining pond which is used as a tourist place based on physics, chemical and biotic indices of Diatoms as bioindicator. Sample water and Diatoms were taken at three post-tin mining pond (Itam, Pedindang, and Jangkang 2) and natural swamp as the reference site. Sampling in each pond and swamp was done in three stations as replications and then physicschemical quality of water were observed (pH, water temperature, turbidity, conductivity, COD, and phosphate) and also the Trophic Diatom Index (TDI) and Pollution Tolerant Value (% PTV) from Diatom as indicator of trophic status and organic pollution. The results of the study showed that all of the ponds and natural swamp had low pH range from 4.32- 6.34. The turbidity of Itam and Pedindang are higher (22-24 NTU) than Jangkang 2 and swamp (3.13-9.13 NTU). Jangkang 2 had the highest conductivity value (115.10 μS.cm-1) and swamp has the lowest (10.64 μS.cm-1). The value of COD and total phosphate in all location still meet the government standard (COD < 20 mg.L-1 and total phosphate < 0.2 mg.L-1). Water quality in post-tin mining ponds is lower than natural swamps based on Diatom as bioindicator. All of the ponds were categorized as moderately polluted based on Shannon Wiener Diversity index of Diatom (H=1.2-1.6), however, the swamp is lightly polluted (H=2.6). Trophic status of water in post-tin mining ponds based on Trophic Diatom Index (TDI) included in the eutrophic while in swamp categorized as mesotrophic. Based on percentage pollution tolerant value (%PTV), the water in Itam and Pedindang included in heavily organic pollution and water in Jangkang 2 and swamp have moderate organic pollution.