Vegetation dynamics and patterns of change in functional protection subzones in Songshan National Nature Reserve, Beijing

Abstract

The nature reserve, as a cornerstone of global ecological conservation, has become the focus for ecological management and design programs. The aim of this study is to describe the differentiation dynam-ics of vegetation in various functional subzones under relevant protection conditions. Based on remote sens-ing, GIS and other methods of landscape analysis, the 1987- and 2001- normalized difference vegetation in-dex (NDVI) data of Songshan National Nature Reserve, Beijing were calculated using two-stage Landsat 5 Thematic Mapper images. Vegetation analysis was analyzed for trends, including three tendencies: decrease, stabilization and increase. Landscape metrics were calculated to portray the change pattern of vegetation, and spatial heterogeneities of vegetation dynamics and change pattern were compared in various functional sub-zones. The major results were achieved as follows: (1) Vegetation cover remained in general stable or was to some extent improved since the nature reserve had been established. The gradients of vegetation cover had already been constructed, i.e. core zone buffer zone experimental zone. (2) Under the strictest protection measures, vegetation in the core zone appeared to be highly stable and had been further improved. The stabi-lization-type vegetation dynamic was found in the central part of the zone and the increase-type dynamic was found on the edge of the zone. The decrease-type vegetation dynamic was consistent with natural vegetationdynamics in a randomly distributed state. (3) As a result of development and exploitation, the stabilization of vegetation in the experimental zone was low and variable, with a strong fluctuation as well as a dynamic of alternating increase and decline. Its vegetation coverage was the lowest and the vegetation tended to degrade gradually. (4) To some extent, a random distribution pattern was observed in the vegetation of the buffer zone.