Plant diversity and aboveground carbon stock along altitudinal gradients in Quezon Mountain Range in Southern Mindanao, Philippines.
Plant diversity, aboveground biomass, and carbon stock along portions of Quezon Mountain Range were assessed in three elevation gradients, e.g., low (400-799 m a.s.l.), middle (800-1,199 m a.s.l.), and high (1,200-1,600 m a.s.l.) in Southern Mindanao using quadrat sampling technique. A total of 146 plant species were identified including threatened Shorea contorta, Parashorea malaanonan, Dillenia philippinensis, Alstonia macrophylla, Cinammomum mercadoi, Palaqium luzoniense, Neolitsea vidalii, Dacrycarpus elatumi, and Dacrycarpus imbricatus. On the average, low diversity was recorded in all gradients particularly in low and middle elevation ranges where alteration of vegetation cover, and proliferation of bio-invasive Piper aduncum were observed. Biomass and carbon stock were largest in high elevation where the inaccessible old growth forest is located compared to a proposed mine site in low and middle elevation that are predominated by grassland, farmlands, disturbed secondary growth forest, and human settlements. Overall, carbon stocks ranged from 33.8 to 192.0 MgC ha-1 suggesting the good potential of the area to mitigate climate change. Sustainable management of biodiversity and carbon stock is needed by apportioning productive and protective zones in the mountain.