TOLERANSI LIMA JENIS RUMPUT TERHADAP MINYAK DAN KAPASITAS DEGRADASINYA DALAM SISTEM FITOREMEDIASI

Abstract

Sistem fitoremediasi berbasis rumput untuk pengelolaan pencemaran lingkungan di tambang minyak telah diteliti. Lima jenis rumput, yaitu Scirpus grossus, Brachiaria humidicola, Eleusine indica, Paspalum notatum, dan Setaria splendida ditanam pada tanah tercemar minyak lama berkadar 3,1%. Pengaruh cekaman salinitas dievaluasi dengan menambahkan air formasi (850 mg/L TDS) ke dalam tanah. Setelah dua belasminggu, parameter pertumbuhan ditetapkan dan kandungan minyak dalam tanah dianalisis. Hasilnya menunjukkan, bahwa semua jenis rumput dapat tumbuh pada tanah tercemar minyak lama. Di bawah cekaman air formasi, jumlah anakan dan berat kering tunas B. humidicola dan S. splendida jelas tertekan, tetapi panjang akar meningkat. Sebaliknya, berat kering tunas pada S. grossus meningkat di bawah cekaman salinitas. Berat kering akar semua jenis rumput secara nyata berkurang dengan cekaman salinitas. Nisbah berat kering tunas terhadap akar relatif tidak dipengaruhi oleh salinitas. Kegiatan degradasi minyak dipengaruhi oleh cekaman salinitas. Kandungan minyak yang hilang dari tanah berkisar antara 32% hingga 50% pada semua jenis rumput.Kata kunci: pencemaran minyak, fitoremediasi, rumput, air formasi Abstract Experiment to develop a grass based phytoremediation system for environmental management in oil industry has been established in the green house. Five species of grasses, i.e. Scirpus grossus, Brachiaria humidicola, Eleusine indica, Paspalum notatum, dan Setaria splendida, were planted in 6.5 kg oil polluted Semanggi soil (oil content of 3,1%). The effects of salinity were evaluated by adding 800 ml of produced water (850mg/L TDS) to the soil. Growth parameters of the plants and the remaining oil content in the soil were determined in the end of week 12th after planting. The results indicated that all of the grass species are capable of growing well in the polluted soil. However, under the salinity stress, the number of buds on the stolons or rhizomes and the shoot dry weight of B. humidicola and S. splendida are reduced significantly. On the contrary,the root length of the two species is increased; and the shoot dry weight of S. grossus is increased. The root dry weight of all tested species are reduced significantly; however the ratio of shoot dry weight to root dry weight is not influenced by salinity stress. Overall, the oil removal rate from the soil is in the range of 32% to 50%; S. grossus and S. splendida are being the best. The oil degradation activity of the two species is slightly increased under salinity stress condition.Key words: oil polluted soil, phytoremediation, grass, produced water