Research on ecological restoration zoning in coastal zone based on landscape ecological risk and ecosystem service value：a case study of Fangchenggang City

The coastal zone of Fangchenggang City was taken as an example, its landscape ecological risk and ecosystem service value in different periods were calculated, the spatial correlation of the two was analyzed using spatial autocorrelation, and the ecological restoration zoning of the national land space in the coastal zone were delineated based on the analysis results. The results showed that from 2000 to 2020, the land use type of the coastal zone of Fangchenggang City was dominated by forest land, accounting for about 50% of the study area, followed by sea area (18%), cultivated land (16%) and construction land (6%), and the type conversion of forest land, sea area and construction land in the coastal zone was the most drastic during the study period. The overall ecological risk level of the study area was dominated by lower ecological risk, which accounted for about 32% of the study area, followed by medium ecological risk (26%), low ecological risk (18%) and higher ecological risk (16%), while the area of high ecological risk was smaller, accounting for only about 8% of the study area. The ranges of lower ecological risk and medium ecological risk showed a trend of shrinking during the study period, while the ranges of low, higher and high ecological risk showed an expansion trend. The value of ecosystem services in the study area showed a trend of "increasing first and then decreasing", with a cumulative decrease of 543 million yuan over the 20 years. Based on the results of spatial clustering analysis of landscape ecological risk and ecosystem service value, the study area was divided into ecological priority restoration area, ecological key restoration area, ecological comprehensive enhancement area, ecological preventive management area and ecological conservation and nourishment area. Ecological restoration measures such as restoration of coastal wetlands, cultivation of agricultural land fertility, management of urban inland waterways, enhancement of the completeness of ecological land use, and promotion of natural regeneration of forests and grasses, etc., were put forward for the different sub-areas, respectively.