The evaluation of ecosystem services is important for islands’ Eco-environment protection and land utilization. For most offshore islands, they are small in area and far away from the mainland with less species and vulnerable ecosystem. Then, the ecosystem services such as soil conservation, carbon storage, habitat quality and water yield are crucial to the sustainability of the island ecosystem. In this thesis, the Miaodao Archipelago was taken as the study area, and the InVEST model was used to quantitatively evaluate the four ecosystem services in 2017, i.e. water yield, carbon storage, soil conservation, and habitat quality. Then the characteristics of the four ecosystem services and the spatial distribution patterns of the trade-off and synergy relationships among these four ecosystem services were investigated. The main results and conclusions were as follows:
(1) The annual water yield of Miaodao Archipelago was 72.2 million m3.The total amount of carbon storage in Miaodao Archipelago was about 46.8 thousand tons, and the average carbon storage is 350.45g / m2.The total amount of soil erosion on Miaodao Archipelago was about 50.63×104 t/a. The low-lying areas were easy to store water yielding and the amount of soil erosion was lower. The habitat quality and the carbon storage in the areas covered with more vegetation was higher than that in the rural areas and tourism areas.
(2) The analysis results of the relationship among these four kinds of ecosystem services showed that: there was a negative correlation between water yield and carbon storage, water yield and habitat quality. Moreover, there was a positive correlation between habitat quality and soil conservation. No significant correlation was detected between water yield and soil conservation, carbon storage and habitat quality.
(3) The ecosystem services for different islands vary greatly, and the spatial distribution showed obvious regional differences. From the view of land cover, the ecosystem services of habitat quality, carbon storage and water production in forest were sound. In terms of elevation, slope and aspect, the ecosystem services varied greatly, and their characteristics were more prominent.
(4) The trade-off and synergy relationships between the four ecosystem services on different regions were different. It was necessary to adjust and control the ecosystem services according to the characteristics of the trade-off and synergy relationships to improve the ecosystem quality.
In conclusion, a quantitative assessment of the ecosystem services as well as the research on the balance and synergy of relationship among the island ecosystem services is helpful to coordinate local economic development and ecological protection, and then supporting the construction of Changdao Marine Ecological Civilization Demonstration Area.