STUDI FITOREMEDIASI SERAPAN BESI (Fe) DARI KOLAM BEKAS TAMBANG BAUKSIT MENGGUNAKAN PURUN (Eleocharis sp.)

Abstract

Abstrak Kolam bekas tambang bauksit di Kelurahan Senggarang, Kota Tanjung Pinang memiliki kandungan besi yang meskipun masih di bawah ambang batas baku mutu, namun berpotensi mengalami biomagnifikasi logam besi. Selain mengandung besi, kolam bekas tambang bauksit tersebut banyak ditumbuhi oleh tumbuhan mencuat yaitu purun (Eleocharis sp.). Air kolam bekas tambang bauksit juga dimanfaatkan warga sekitar untuk mandi dan mencuci. Tujuan penelitian ini yaitu untuk mengetahui kemampuan purun menyerap besi (Fe) dari air kolam bekas tambang bauksit di Kota Tanjung Pinang. Penelitian dilakukan melalui eksperimen di laboratorium menggunakan rancangan acak lengkap terhadap biomassa purun yang berbeda, yaitu 250 g, 500 g, dan 0 g (kontrol) selama 30 hari. Penelitian ini menunjukkan perbedaan yang nyata antara perlakuan biomassa purun 250 g dan 500 g dalam menyerap besi dari hari ke-0 hingga hari ke-30. Biomassa purun 500 g mampu menyerap besi sebesar 80,1%, sedangkan kemampuan penyerapan besi biomassa purun 250 g hanya 17,1%. Penelitian ini mengonfirmasi bahwa akar purun lebih efektif dalam menyerap dan menyimpan logam besi daripada bagian batang. Kata kunci: fitoremediasi, besi (Fe), purun (Eleocharis sp.), tambang bauksit, Tanjung Pinang Abstract Phytoremediation Study of Iron (Fe) Absorption from Former Bauxite Mine Ponds Using Hairgrass (Eleocharis sp.) . The former bauxite mining ponds in Senggarang Village, Tanjung Pinang City showed iron content which, although still below the permitted threshold, has the potential to experience metal iron biomagnification. In addition to containing iron, these former bauxite mining ponds are overgrown with emergent aquatic plants, such as hairgrass (Eleocharis sp.). The water from these ponds is also used by local residents for bathing and washing. The purpose of this study was to determine the ability of hairgrass to absorb iron (Fe) from bauxite mining pond water in Tanjung Pinang City. The research was conducted through laboratory experiments using a completely randomized design method on different hairgrass biomass, i.e. 250 g, 500 g, and 0 g (control) for 30 days. This study showed a significant difference between the treatment of hairgrass biomass of 250 g and of 500 g in absorbing iron from day 0 to day 30. The hairgrass biomass of 500 g was able to absorb iron up to 80.1%, while the iron absorption capacity of 250 g of hairgrass biomass was only 17.1%. This study confirmed that hairgrass roots were more effective at absorbing and storing ferrous metals than the stems. Keywords: phytoremediation, iron (Fe), hairgrass (Eleocharis sp.), bauxite mine, Tanjung Pinang