关键词: 景观格局, 景观指数, 尺度效应, 梯度分析, 惠州

Abstract: We integrated landscape metrics, gradient analysis, and moving window method to analyze the spatial variations of landscape pattern in Huizhou. The radiative gradient zones were set around the downtown by expanding outward at equal distances. Four transects with different directions were set according to the characteristics of the study area. The grain effect analysis of landscape metrics and the land area change evaluation index model were used to determine the appropriate grain for the study area. Considering the anisotropy of landscape pattern, the appropriate spatial extents for different transects were determined by calculating the semivariogram and the corresponding nugget-sill ratio in different directions. The landscape patterns along transects in different directions were analyzed with moving window method. The results showed that: (1) 50 m was an appropriate grain extent for the study area, and the moving window sizes for the four transects were 750, 850, 1350 and 1150 m, respectively. (2) From the center to the periphery, Huizhou can be divided into downtown, agricultural area, urban sub-center area, transition area, and ecological conservation area. (3) Most highly urbanized and exurban areas presented a single landscape component with exclusive advantages. In contrast, the landscape heterogeneity and fragmentation increased in the urban fringe and urban-rural transition zone. (4) Analysis of landscape pattern of different transects can reflect the directional differentiation of the research area, which is an effective means for urban landscape gradient analysis.

Key words: landscape pattern, landscape metrics, scale effect, gradient analysis, Huizhou.