Land-Use Change And Ecosystem Services Evaluation In The Islands City, Based On Remote Sensing

Ecosystem services are the conditions and processes through which natural ecosystems, and the species that make them up, sustain and fulfill human life. They are the cornerstone of human survival and sustainable development of society. Islands owning special location are considerably fragile and highly sensitive to human activities. Zhoushan is the only city of Zhejiang Province consisting solely of islands and also the first state-level new area of marine in China. It consists of a number of islands and has a long coastline. Recently, owing to new urbanization strategy and the rapid development of marine economy, Zhoushan is in a hurry to exploit the urban and reclaim new land, resulting in a serious of significant changes in land structure and ecosystem services and potentially posed threats into island environment. Combining multi-date remote sensing images and data of topography, soil, meteorology and social economy, in this research we analyzed spatial-temporal dynamic of land-use changes trigged by rapid urbanization and rampant reclamation. We further evaluated the trajectory of ecosystem services change including biodiversity, soil conservation, hydrology regulation, carbon storage and production supplement. This study finally revealed the potential role of ecosystem in supporting the ecological safety and social development and the dynamic interaction between human activities and ecosystem. Main conclusions are as follows:(1) Owing to rampant reclamation, the monitoring area of Zhoushan city increased significantly from 1271.82 km2 in 2000 to 1376.23 km2 in 2010. Among the extended areas by reclamation,47.58% of them were used for urban construction, and 23.67% turned into water bodies for aquaculture.(2) The main type of land use was forest, followed by farmland and urban land. From 2000 to 2010, forest and farmland area decreased, while urban area increased dramatically. And the area which transferred from farmland and forest to urban land accounted for 80.27% and 50.58% of respective transfer area.(3) Product supplement was found as the most prominent ecosystem service of Zhoushan, followed by soil conservation, carbon storage, biodiversity, and hydrological regulation was the weakest. During 2000-2010, product supplement service improved significantly; Soil conservation service and carbon storage service increased slightly. Hydrological regulation service remained stable; biodiversity service declined slightly.(4) Carbon storage, hydrological regulation and soil conservation service correlated significantly indicating obvious synergies. However, biodiversity negatively correlated with them which resulted from the radiation distribution of land use in "Forest-Farm-Urban" type.(5) The impacts of forest and farmland on ecosystem services were serious, especially forest. They were in significant positive correlation with carbon storage, hydrological regulation, and soil conservation.