Research On Spatial Scale Effect Of Land Use Landscape Pattern

Spatial scale effect research is one of the important contents of landscape pattern analysis. Analyzing the scale effect of landscape pattern and identifing the characteristic scale can help to accurately reflect the characteristics of land use pattern,provide a scientific basis for establish scientific and reasonable land use planing and formulate the effective measures to control land use. Currently, the more study of spatial scale effect is maken from the angle of size change, while those from the angle of extent change is less. In this paper, based on geographic information systems,spatial scale effect of land use pattern were studied using extent changing method under different scale in Yongdeng country of Lanzhou city, Gansu Province, China.The results showed that:(1).The patch level index and the landscape level index all showed obvious dependence with the increase of spatial extent. Scale effect of patch level index and landscape level index in different extent interval all existed difference.(2).According to the change characteristic curve of scale effect,the scale effect of patch level index and landscape level index can be divided into three intervals:Within the extent range of 1 ~ 20 km, scale effect showed the most obvious difference between patch level and landscape level. Within the extent range of 21 ~ 90 km, scale effect showed smaller difference between patch level and landscape level. When the extent range more than 90 km, in patch level and landscape level, the difference of scale effect were not obvious and scale effect disappeared.(3).For the scale dependence, scale dependence(the coefficient of variation range was 0.03~29.57%)of landscape level was weaker than scale dependence(the coefficient of variation range was 0 ~ 458%)of patch level.(4).The effective extent of scale dependence was 100km(10000 km2). When the extent exceeded the scale dependence range, study of landscape pattern would be meaningless. And in this extent, there were at least two characteristic scales, the first one was about 20 km, and the second one was about 90 km.