Spatial heterogeneity of landscape ecological risk of typical islands in Beibu Gulf based on honeycomb grid

Based on the landscape pattern index data of typical islands in the Beibu Gulf, ecological risk assessment model, spatial autocorrelation model and variation function model was used to analyze the ecological risk of different islands. ① The best fitting model for ecological risk of Qixing island was Gauss model, and its nugget coefficient was 0.06780, while Tuanhe island was 0.01225. It showed that the landscape pattern index of Qixing island was mainly controlled by random factors, while Tuanhe island was controlled by structural factors. ② The Tuanhe island with structural factors can be moderately developed, while the Qixing island with random factors can be properly protected. ③ The ecological risk value of Tuanhe island showed a spatial pattern of “high in the southeast and low in the southwest ”, while the ecological risk value of Qixing island showed a spatial distribution pattern of “high in the west and low in the east, high in the south and low in the north ”. ④ The lithology played a key role in the formation of the island landscape pattern. The bedrock island was hard rock, and the landscape pattern had a certain stability; while the sediment island was the alluvium and the landscape pattern was easily disturbed by natural and man-made conditions. An ecological risk assessment method based on Geostatistics theory proposed in this paper can provide reference for the theory and method of island natural resource management in Beibu Gulf of Guangxi.