Potential ecosystem service values of mangrove forests in southeastern China using high-resolution satellite data

Mangrove forests provide a large number of important ecological, economic, and social benefits. This study proposes a pixel-based method for estimating the spatial variability of mangrove ecosystem services (coastal protection, carbon sequestration, nutrient retention and heavy metal retention) in the Jiulong River Estuary using a combination of high-resolution satellite data with market price and replacement cost approaches. The results indicated that there was a considerable variability in the ecosystem service values caused by the distance of mangroves to the coast and the different growth phases of mangrove forests. The total estimated value of the four selected ecosystem services was US$ 287,993/year for 174.58 ha (approximately US$ 1650/ha/year). Coastal protection was estimated to provide the highest value (US$ 239,683/year), amounting to 83.23% of the total value of the ecosystem services, followed by nutrient retention (US$ 25,283/year), contributing 8.78% of the total value of the ecosystem services and accounting for up to 52.33% of the total value of regulating services. Heavy metals retention (US$ 10,289/year) and carbon sequestration (US$ 12,738 in 2015/year) had relatively low values in comparison to those of coastal protection and nutrient retention. However, there was an underestimation of mangrove ecosystem services because we did not consider other services, such as fisheries, biodiversity, recreation, education and tourism, mainly due to the lack of primary data. Nevertheless, the estimated economic value of mangrove ecosystem services in this area is meaningful to raise awareness of the benefits provided by mangroves to local communities and policy makers.