Carbon sequestration potential of seagrasses species in the selected sites of Don Marcelino, Davao Occidental, Philippines

Abstract

The study determined the carbon sequestered by seagrasses from the three (3) coastal sites of Don Marcelino, namely Talagutong, Kinanga, and Lawa. The study employed one-shot sampling as part of a preliminary survey visit at the study sites. The survey was conducted during the lowest tide of the day, and the observation of seagrass species was limited to a depth of 0–3 meters. A total of four species of seagrasses were identified using taxonomic field guides. The species Halodule pinifolia, Thalassia hemprichii, and Cymodocea rotundata were present in Talagutong, while Thalassia hemprichii, Cymodocea rotundata, Halophila ovalis, and Halodule pinifolia were recorded in Kinanga and Lawa. Thalassia hemprichii is the most dominant seagrass species and has the highest percent cover, followed by Cymodocea rotundata. Moreover, Thalassia hemprichii is more dominant in the study area, which also obtained the highest shoot density, followed by Cymodocea rotundata. Cymodocea rotundata obtained the highest sequestered total carbon from Lawa compared to the other two (2) sites. The carbon sequestered by Thalassia hemprichii in Talagutong and Lawa is significantly higher compared to Kinanga. Furthermore, the carbon sequestered by Halophila sp. in Lawa and Kinanga is significantly higher (21.56 and 18.56 (g/m²) than in Talagutong. It is highly recommended to the local government units to include seagrass areas of Don Marcelino into marine protected areas as a part of the implementation of proactive climate change mitigation.