| Landscape pattern and system coupling of the meta-ecosystem of mountain, desert and oasis in Hexi Corridor, Gansu, China is analyzed with remote sensing and GIS. The results show that:1) The meta-ecosystem of mountain, desert and oasis in Hexi Corridor, Gansu, China is made up of 5 landscape ecosystems that are mountain, desert, oasis, water region and road. Desert have the biggest area, it is the matrix and plays the dominant role in the functioning of the meta-landscape system; mountain and oasis are the patch; while water region and road play the role of the corridor.The mountain landscape ecosystem is made up of 10 landscape elements types, that are residence land, cultivated land, mountain desert, mountain grassland, mountain forestland, sub-mountain vegetation, mountain vegetation, ice and snow, river and road. Of thesis, mountain covers the most proportion of the mountain landscape ecosystem and most connected, so it plays the role of matrix; river and road, the corridor; the other landscape elements, the patch. The desert landscape ecosystem is made up of 4 landscape elements types that are rocky desert, sandy desert, conglental desert and road. Of thesis, conglental desert has the biggest area and most connected, it is the matrix of the desert landscape ecosystem; road, the corridor; rocky desert and sandy desert, the patch.The oasis landscape ecosystem is made up of 10 landscape elements, that are residence land, cultivated land, grassland, forestland, water region, road, rocky desert, sandy desert and conglental desert. Of thesis, cultivated land covers the most of the area and most connected, it is the matrix of the oasis landscape ecosystem; water region and road, the corridor; the others, the patch.2) The type of the landscape elements is broader than the type of the grassland and the vegetation, but the three classifications all are hierarchy relying on the scale. The types of the grassland or vegetation are types of the grassland or vegetation too, while one type is divided into different types through the hierarchy classification. But in the landscape classification hierarchy, the different divisions of a landscape cannot be called landscape again, on the other0hand, they are landscape element of the landscape pattern, and play the roles of matrix, patch or corridor according to their area, shape size and connectivity, then they can be categorized according to their origins or causative mechanisms. The classification of landscape type is aim to cover the entire area, in some degree which can be told the classification of land use, while the classification of grassland or vegetation is only concern about the region coved by grasses or vegetation.3) The relative frequency (f) of desert, mountain, oasis, water region and road in meta-landscape ecosystem are 57.5%. 20.7%, 23.4%, 8.1% and 7.3%, respectively, that suggests that desert is the dominate landscape element and plays the matrix which controlling the function and pattern of the meta-landscape ecosystem. The coverage information amount (H) of thesis landscape elements are 22.10, 35.50, 29.00, 17.81 and 16.80 bite, respectively, desert has the highest volume of H, while water region gets the smallest. Mountain has the biggest change value (CV) of H, 83.12%; oasis gets the secondary CV, 64.07%; desert gets the smallest, 45.21%. That suggests that the desert is the most stable landscape element, spatial heterogeneity of mountain gets more changes than the other elements in the meta-landscape ecosystem. The spatial heterogeneity of desert is homogeneous heterogeneity because its relative frequency is bigger than 50%, however, the spatial heterogeneity of other landscape elements in meta-landscape ecosystem is heterogeneous heterogeneity. So. increasing the relative frequency of oasis, water region and road or decreasing the relative frequency of desert to 50% around are practical ways to maintain and progress the entire spatial heterogeneity of the meta-landscape ecosystem.4) No matter what direction or coverage in all d...
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