PEMANFAATAN KOLAM PENGENDAP TAMBANG BATUBARA UNTUK BUDIDAYA IKAN LOKAL DALAM KERAMBA

Abstract

Uji coba budidaya dalam keramba telah dilakukan untuk mengetahui kelayakan kolam pengendap tambang batubara untuk areal budidaya ikan bagi masyarakat sekitar apabila kegiatan tambang telah ditutup, serta untuk mengetahui apakah produk ikan yang dihasilkan cukup aman untuk dikonsumsi manusia. Percobaan dilakukan pada bekas kolam pengendap DS2 milik PT KPC, dengan mengunakan 5 buah keramba apung berukuran 3 m x 1 m x 1 m yang dalam setiap keramba ditebar benih dari alam untuk ikan repang (Barbodes schwanenfeldii) ukuran rata-rata 20,2 g; puyau (Osteichilus kappenii) ukuran 66,1 g; dan mas (Cyprinus carpio) ukuran 28,96 g dari pemijahan di laboratorium sebanyak masing-masing 200 ekor, serta pepuyu (Anabas testudineus) ukuran rata-rata 41,4 g dari alam sebanyak 50 ekor, udang galah (Macrobrachium rosenbergii) ukuran 113,8 g juga dari alam sebanyak 50 ekor. Pakan diberikan secara sampai kenyang (ad libitum). DO, pH, suhu, DHL, dan kekeruhan diukur harian, sedangkan ikan diukur pertumbuhan bobotnya. Setelah dipelihara selama 4 bulan dan memenuhi ukuran konsumsi, ikan dan udang diperiksa kandungan Sb, Se, As, Hg, Mn, Cd, Fe, Cu, Pb, dan Zn. Hasil penelitian menunjukkan bahwa bekas kolam pengendap tambang batubara cukup layak untuk dikembangkan sebagai areal budidaya ikan dengan memberikan pertumbuhan bobot populasi sebesar 570,79% (repang, SR: 95%), 202,57% (puyau, SR: 97%), 573% (mas, SR: 2,5%), 238,92% (udang galah, SR: 10%), 447,10% (pepuyu, SR: 14%) dan produknya cukup aman untuk dikonsumsi, dengan kandungan Sb (0,24-2,45 mg/L, rasio terdeteksi dari sample: 100%), Se (0,00-0,06, 57,14%), As (tidak terdeteksi/ttd), Hg (0,00-0,06 mg/L, 50%), Mn (ttd-1,68 mg/L, 14,29%), Cd (ttd), Fe (ttd-5,45 mg/L, 7,14%), Cu (ttd), Pb (ttd), dan Zn (7,82-61,50 mg/L, 100%).

The experiment was conducted to study the feasibility of settling or sedimentation pond of coal mining to be used for culturing fish in net cage for local people post  mining activities. Experimental 3 m x 1 m x 1 m of 5 floating net cages were located in DS 2, an abandoned settling pond owned by Kalimantan Timur Prima Coal (KPC). Each cage was stocked with natural barb seed (Barbodes schwanenfeldii) with mean weight of 20.2 g, fresh water carp or puyau (Osteichilus kappenii) with mean weight of 66.1 g, and common carp (Cyprinus carpio) with mean weight of 28.96 g from fish hatchery with density of 200 seeds per species per cage, wild seed of climbing pearch (Anabas testudineus) with mean weight of 41.4 g and density of 50 seeds per cage, and giant prawn (Macrobrachium rosenbergii) with mean weight 113.8 g and density of 50 seeds per cage. The fishes were feed ad libitum. Water quality parameters were measured daily consisting of DO, pH, temperature, conductivity, and turbidity, while fish growth was determined by measuring its weight. After 4 months of rearing and reached marketable size, the fish were then measured for the evidence of Sb, Se, As, Hg, Mn, Cd, Fe, Cu, Pb, and Zn. The result shows that the settlement pond of coal mining is feasible to rear fish in cage. The recorded fish growths were 570.79% for barb fish with survival rate/SR: 95%, 202.57% for local carp with SR: 97%, 573% for common carp with SR:2.5%), 238.92% for giant prawn with SR:10%), 447.10% for climbing perch with SR:14%. All of the reared fish are safe to be consumed because they have normal content of Sb (0.24 to 2.45 mg/L, and detected ratio in all sample was: 100%), Se (0.00 to 0.06; 57.14%), As (not detected/nd), Hg (0.00 to 0.06 mg/L, 50%), Mn (nd to 1,68 mg/L, 14.29%), Cd (nd), Fe (nd-5.45 mg/L, 7.14%), Cu (nd), Pb (nd), and Zn (7.82-61.50 mg/L, 100%).