[Regional ecosecurity pattern in urban area based on land use analysis: a case study in Lanzhou]

Mid-scale regional ecosecurity, which takes practical ecosecurity issues as its priority, should be viewed as the core of the multi-scale concept of ecosecurity. For urban area, a special region taking ecological infrastructure as its core mission, the construction of regional ecosecurity pattern may provide a good chance to realize its sustainable development. Based on land use analysis, a qualitative and quantitative research on the landscape pattern, ecovalue evaluation, and driving force analysis of social economy could provide an effective approach to construct the ecosecurity pattern in urban area. This study showed that in Lanzhou, the ecosecurity pattern consisted of three parts, i.e., eco-safeguarding system, eco-buffering system and eco-percolating system, among which, eco-buffering system was the decisive part determining ecosecurity pattern construction. The quantitative analysis of urban spatial expansion pattern was taken as the decisive function to determine the security level of the ecosecurity pattern, which was divided into low, middle and high levels.