Pengaruh Kedalaman Sedimen Terhadap Emisi Gas Metana (CH4) di Situ Kuru

Abstract

Sedimen perairan situ merupakan salah satu sumber emisi gas metana (CH4)  penyebab efek gas rumah kaca. Tujuan penelitian ini adalah untuk mengetahui potensi emisi gas metana (CH4) di Situ Kuru secara in situ berdasarkan kedalaman sedimen. Pemilihan lokasi diambil menggunakan teknik purposive sampling di 3 tempat yaitu inlet, tengah dan outlet. Sifat fisika dan kimia air yang diukur pada penelitian ini adalah suhu air, pH air, Total Dissolved Solids (TDS), konduktivitas, Dissolved Oxygen (DO), dan Biochemical Oxygen Demand (BOD5). Analisis sedimen meliputi pH, BO, rasio C/N, VFA parsial, NH3, dan analisis mikroorganisme. Analisis sampel gas metana (CH4) dan gas karbondioksida (CO2) dilakukan dengan menggunakan gas analyzer. Analisis kimia fisik air dan sedimen membuktikan bahwa sedimen Situ Kuru mampu mendukung aktivitas mikroorganisme metanogen. Hasil menunjukkan bahwa sedimen Situ Kuru memiliki potensi untuk menghasilkan emisi gas metana (CH4) yang berbeda pada setiap daerah inlet, outlet dan tengah. Hasil juga menunjukkan bahwa nilai fluks gas metana (CH4) dipengaruhi kedalaman sedimen. Hasil fluks gas metana (CH4) metana tertinggi terdapat pada kedalaman 0-30 cm lokasi tengah sebesar 5,5790 mg/m2/jam. Fluks gas metana (CH4) dipengaruhi pula oleh keberadaan gas karbondioksida (CO2). Fluks gas karbondioksida (CO2)tertinggi terdapat pada kedalaman 0-30 cm lokasi tengah sebesar 2,3910 mg/m2/jam. Berdasarkan penelitian ini maka perlu dilakukan rehabilitasi terhadap Situ Kuru karena turut berperan dalam emisi gas metana (CH4) dengan kisaran 0,0290-5,5790 mg/m2/jam.ABSTRACTSediment in the waters is one of the sources of methane gas emissions that cause the greenhouse gas effect. The purpose of this study was to determine the potential for methane (CH4) emissions at Situ Kuru in situ based on the depth of the sediment. The location selection was taken using purposive sampling technique in 3 places, namely inlet, middle and outlet. The physical and chemical properties of the air measured in this study were air temperature, air pH, Total Dissolved Solids (TDS), conductivity, Dissolved Oxygen (DO), and Biochemical Oxygen Demand (BOD5). Sediment analysis includes pH, BO, C/N ratio, VFA, NH3, and microorganism analysis. Analysis of methane gas (CH4) and carbon dioxide (CO2) gas samples was carried out using a gas analyzer. Physical chemistry analysis of air and sediment proved that the Situ Kuru sediment was able to support the activity of methanogenic microorganisms. The results show that the Situ Kuru sediment has the potential to produce different methane (CH4) emissions at each inlet, outlet and middle area. The results also show that the value of methane gas flux (CH4) is influenced by the depth of the sediment. The results of the highest methane gas flux (CH4) of methane were found at a depth of 0-30 cm in the middle location of 5.5790 mg/m2/hour. The flux of methane (CH4) is also influenced by the presence of carbon dioxide (CO2) gas. The highest flux of carbon dioxide (CO2) is found at a depth of 0-30 cm in the middle location of 2.3910 mg/m2/hour. Based on this research, it is necessary to rehabilitate Situ Kuru because it plays a role in methane (CH4) emissions in the range of 0.0290-5.5790 mg/m2/hour.