A GIS-based gradient analysis on landscape pattern of Tongzhou District of Beijing, China

The gradient variance and spatial stability associated with landscape pattern were investigated for fast urbanization area of Tongzhou District of Beijing by combining spatial network sampling technique, landscape metrics and gradient analysis. A newly integrated indicator, Landscape Stability Index (LSI) is established by combing related landscape metrics to reflect the potential landscape dynamics. The results shows that landscape change in Tongzhou exhibits distinctive spatial differences along transects from urban center to rural areas, characterized by higher fragmentations at urban fringes and newly urbanizing areas. In addition, the landscape stability index of Tongzhou is from 0.204 to 1, with mean value of 0.4436, indicating relatively low landscape stability level with intensive transformation and conversion of landscape and obvious spatial difference. The rapid landscape converting area (with low LSI value) consists of the arc-shaped area surrounding central Tongzhou city and its vertical zone along Beiyun River to southeastern direction.