Study of Greenhouse Gases: Nitrous Oxide (N₂O) Emissions in the Seagrass Beds of Tanjung Tiram and Halong Beach, Inner Ambon Bay

N2O gas is the third largest contributor to global warming at 7.9% after CO2 76.7% and CH4 14.3%. Although the concentration of N2O is smaller than CO2 and CH4 in the atmosphere, which are the largest contributors to global warming, it has a relatively long lifetime of 150 years. Coastal ecosystems such as seagrass ecosystems, in addition to having the ability to absorb greenhouse gases, can also release N2O gas due to organic matter originating from land and litter from seagrass itself. Research on the concentration and emissions of greenhouse gases in seagrass beds is still minimal. Therefore, research on N2O gas emissions needs to be conducted to provide additional scientific information on greenhouse gas emissions in the Tanjung Tiram and Halong Beach seagrass areas, Ambon Dalam Bay. This research was conducted in June - September 2023. Gas sampling was carried out by placing a cover on the sediment in the seagrass beds according to the dominant species living there. The gas that has been taken is then put into a 10 ml vial bottle to be analyzed for greenhouse gas concentration in the greenhouse gas laboratory of the Agricultural Instrument Standardization Agency (BSIP) of Pati Regency, Central Java. After the greenhouse gas concentration value is obtained, the carbon emission value analysis is carried out. Statistical analysis for N2O gas concentration using single factor ANOVA. The highest N2O concentration at the Tanjung Tiram location was found in the Thalassia hemprichii species 0.372 ppm and the lowest in the Enhalus acoroides species 0.355 ppm while the highest N2O concentration at the Halong Beach location was found in the Halodule pinifolia species 0.376 ppm and the lowest in the Cymodocea rotundata species 0.346 ppm. The highest N2O emissions at the Tanjung Tiram location were in the H. pinifolia species 0.01289 mg/m2/hour and the lowest in the T. hemprichii species 0.00484 mg/m2/hour, while the highest N2O emissions at the Halong Beach location were in the T. hemprichii species 0.00923 mg/m2/hour and the lowest in the H. pinifolia species 0.0183 mg/m2/hour.