Dampak Aktivitas Perkotaan dan Penambangan Nikel Terhadap Tingkat Kontaminasi Logam Berat dalam Air Laut dan Sedimen (Impact of City Activities and Nickel Mining Toward Heavy Metal Contaminant in the Seawater and Sediment)

Teluk Kendari dan Teluk Lasolo yang terletak di Sulawesi Tenggara banyak menerima limbah berasal dari beberapa sungai yang bermuara ke teluk tersebut dan dari kegiatan penambangan logam nikel di daratan dan kawasan pantai. Limbah tersebut mengandung berbagai macam bahan kontaminan, termasuk logam berat. Tujuan penelitian adalah untuk mengetahui tingkat kontaminasi logam berat dalam air laut dan sedimen di perairan Teluk Kendari dan Teluk Lasolo dalam kaitannya untuk kepentingan biota laut. Pengukuran kadar logam berat Pb, Cd, Cu, Zn dan Ni dalam air laut dan sedimen di Teluk Kendari dan Teluk Lasolo. Contoh air laut diambil dengan menggunakan Rosette Water Sampler dan sedimen dengan gravity core pada 10 stasiun penelitian. Kadar logam berat diukur dengan menggunakan Spektrofotometer Serapan Atom (SSA). Hasil penelitian menunjukkan kadar logam berat Pb, Cd, Cu, Zn dan Ni dalam air laut dan sedimen di Teluk Lasolo lebih tinggi dibandingkan dengan Teluk Kendari. Tingginya kadar ke lima logam berat di Teluk Lasolo ini disebabkan oleh limbah yang berasal dari aktivitas penambangan nikel di kawasan darat dan pantai Lasolo. Hasil penelitian ini menunjukkan bahwa kadar ke lima logam berat di kedua perairan teluk ini masih aman untuk biota laut. Kata kunci: sedimen, air laut, logam berat, pencemaran Lasolo, Kendari Kendari and Lasolo Bay which were situated in Southeast of Sulawesi. Both of Bay have been received a lot of waste originated from a variety of activities in Kendari City and Nickel mining activities in the land and in coastal area of Lasolo region. Waste contains a variety of materials contamination, one of these contaminants are heavy metals. The aim of this research is to determine the level of heavy metal contamination in seawater and sediment in Kendari and Lasolo Bay in their relation to the interests of marine organisms. Measurement of levels of heavy metals Pb, Cd, Cu, Zn and Ni in sediment in the Kendari and Lasolo Bay has been done in June 2011. Seawater and sediment samples have taken by using a Rosette water sampler and gravity cores at 10 research stations. Heavy metal levels were measured by Atomic Absorption Spectrophotometer (AAS). The results showed that the concentration of heavy metals Pb, Cd, Cu, Zn and Ni in seawater and sediments in Lasolo Bay is higher compared to Kendari Bay. This condition is believed to be attributable from the nickel mining activities in the land and coastal area of Lasolo. Generally, the concentration of those heavy metals in both of that bay still saved for marine organism Keywords: sediment, seawater, heavy metal, pollution Lasolo, Kendar