Penyerapan Karbon Pada Vegetasi Lamun Di Pantai Legon Bajak Pulau Kemujan, Taman Nasional Karimunjawa

Abstract

Gas karbondioksida yang tinggi di atmosfer dapat memicu pemanasan global. Upaya mitigasi diperlukan untuk mengurangi dampak buruk, salah satunya dengan pemanfaatan lamun sebagai penyerap karbon yang dikenal dengan  blue carbon. Penelitian ini bertujuan mengetahui estimasi biomassa dan kandungan karbon pada vegetasi lamun di Pantai Legon Bajak Pulau Kemujan, Taman Nasional Karimunjawa. Penelitian dilakukan pada 28 – 29 November 2021 dengan dua stasiun. Analisis vegetasi dilakukan menggunakan metode line transect quadrant, yang mengacu pada buku Panduan Monitoring Padang Lamun LIPI. Pengambilan sampel lamun menggunakan seagrass core. Biomassa lamun terbagi menjadi bagian atas substrat (daun) dan bawah substrat (akar dan rhizoma). Nilai biomassa lamun ditentukan melalui berat kering dari dengan cara pengeringan. Nilai kandungan karbon diperoleh melalui metode LOI (Loss of Ignition) atau pengabuan kering.Hasil penelitian diperoleh 5 jenis lamun, antara lain Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis dan Halodule uninervis. Kondisi padang lamun tergolong memiliki penutupan sedang. Nilai biomassa yang terdapat di bawah substrat (585 g/m²) lebih besar dibandingkan yang terdapat di atas substrat (346,73 g/m²), diikuti dengan kandungan karbon di bawah substrat (182,54 gC/m²)yang lebih besar dibandingkan atas substrat (119,43 gC/m²). Vegetasi lamun di lokasi penelitian berpotensi menyimpan karbon sebesar 301,97 gC/ m².

The high level of carbondioxide gas in the atmosphere can trigger global warming. Mitigation efforts are needed to reduce adverse impacts, such as by the optimization of seagrass as a carbon sink which is known as blue carbon. This study aims to determine the estimation of biomass and carbon content in seagrass vegetation at Legon Bajak Beach, Kemujan Island, Karimunjawa National Park. The research was conducted on 28 – 29 November 2021 at two stations. Vegetation analysis was conducted by using the line transect quadrant method, which refers to the LIPI Seagrass Monitoring Guidebook. Seagrass sample was collected by using seagrass core. Seagrass biomass is divided into above substrate (leaves) and below substrate (roots and rhizomes). The value of seagrass biomass was determined through dry weight by drying process in the oven. The value of carbon content in seagrasses is obtained through the LOI (Loss of Ignition) method or dry ignition.The results o the study obtained 5 species of seagrasses, including E. acoroides, T. hemprichii, C. rotundata, H. ovalis and H. uninervis. The condition of seagrass meadows is classified as having moderate cover. The value of the biomass below substrate (585 g/m²) is greater than the value of biomass above the substrate (346.73 g/m²), followed by the value of carbon content below the substrate (182.54 gC/m²) which is greater than above substrate (119.43 gC/m²). Seagrass vegetation in the study site has the potential to store 301.97 gC/m² of carbon.