Presented during the 7th Mangrove Macrobenthos Management Meeting in Ishigaki, Okinawa, Japan. 

Matthew Vincent Tabilog, Polynne Dira, Tara Abrina, Abegail Gelantaga-an, Shiena May Espenida, Rey Lagutin, Dina Lagutin, Leonel Sanier, Quiresa Mae Montaño, Rey Obeda, Jayson Dela Fuente, Dixon Gevaña

Abstract:

Mangrove forests are known to provide a variety of ecosystem services and socio-economic benefits, including climate resilience, protection, biodiversity, and sustenance to wildlife and local communities. Estimating the economic values of this habitat is important for supporting mechanisms in developing policies and financing conservation and restoration strategies.  This is the first study to estimate the economic value of the ecosystem services of mangrove forests in the 227-hectare Bulanon-Lapuslapus-Macapagao Local Conservation Area (BLM-LCA) in Sagay City, Philippines. First, using the benefit transfer method, we estimate the provisioning services of the BLM-LCA, including fishing and gleaning, to amount to PHP 188 million (USD 3,182,200); regulation and maintenance services, including coastal protection and carbon sequestration, are approximated to be valued at PHP 490 million (USD 8,304,267); and cultural services from tourism to be around PHP 742,000.00 (USD 12,567). Using results from previous mangrove valuation studies in the Philippines, which utilized a contingent valuation method, we also estimate the conservation value of the Sagay LCA to be PHP 306,000.00 (USD 5,195). To further validate and refine the values of the mentioned services, a participatory economic valuation was conducted with different sectors of the local community. Because the BLM-LCA is co-managed by the locals and the local government, it is of interest to look into which ecosystem services are deemed most important and valued by the community. Results from the benefit transfer method are then compared with that of the participatory economic valuation. Given these values, we recommend that mangrove forests be conserved and protected in order to sustain the equitable delivery of their vital services to people who directly benefit from the mangroves’ services and other stakeholders.

Presented during the 73rd Meeting of the Ecological Society of Japan in Kyoto University, Japan

Matthew Vincent TABILOG, Yuan YAO, Seishiro KODA, Sota KANNARI, Masahiro NAKAOKA

Abstract:

Seagrasses are a group of marine phanerograms that form extensive meadows in the intertidal and shallow sublittoral parts of the coastal areas of the world. These marine plants provide ecological functions and socioeconomic benefits contributing to habitat complexity, food security, coastal protection, and climate resilience through their ability in sequestering potential amounts of atmospheric carbon. In this study, we examined spatiotemporal variation in eelgrass (Zostera marina L.) in relation to environmental drivers in two coastal lagoons in Eastern Hokkaido, Furen and Notsuke, which are the two largest eelgrass beds in Japan. Field surveys were conducted across 5 stations in each site on a monthly or bimonthly basis from May until October 2025 with in situ measurements of abiotic environments such as temperature, salinity, and depth. Eelgrass were collected quantitatively using a 15 cm diameter core, and the aboveground and belowground biomass of eelgrass, as well as that of epiphytic microalgae attached on eelgrass leaves were then measured and compared among stations, sites and months. Results of the study showed that biomass of eelgrass and epiphytes in each site had a large spatial and temporal variation. Temperature and salinity influenced the growth of eelgrasses in the coastal lagoons and their biomass and shoot density increased steadily from May, reaching peak values in August, followed by a gradual decline. Carbon sequestration rates estimated from the measured biomass and absorption potential by the literature were found to be in the median range reported in different blue carbon ecosystems. The obtained data and estimates can be used as a baseline for conducting effective conservation and management of these coastal ecosystems, especially for utilizing seagrass beds as means for climate mitigation.