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Driven by anxiety of population growth and decline of living standard of human beings, Research on environment in arid zone has been received significant attention in recent years. The flourishing landscape ecology provides a suitable way to study on environment. Meanwhile, the application of RS techniques brings essential data for landscape study. Integration both of them promotes study on environment. Among them, as key substances, the landscape pattern analysis is one of good methods to discuss regional environment. Although a number of papers about it have been published, little practical work has been done for arid zone in China. For these reasons, it is very important and urgent to understand the landscape pattern characteristics and environment trends in arid zone in China, especially in continental river basin in west of China.
Supported by the modern techniques of RS, GIS and GPS and CBERS-1 data and aerial photograph, using the methods of landscape pattern analysis, the paper analyzed the landscape pattern characteristics and environment trends in the middle reaches of Hetian River. The main conclusions has been given as follows:
(1) On macroscale, there have two kinds of typical deserted landscape patterns in arid zone: in the north of region, dominated by river corridor, the landscape is symmetrically distributed with waters and wetland-forestry and grass based on desert matrix; in the south of the region, indicated central line by river, linked by sub-rivers and irrigation canal network, the landscape shows artificial oasis with primary cultivated lands on desert matrix.
(2) Compared landscape pattern figures of 1959 with the one of 2000 and measured values of landscape patterns, fragmentation of each landscape types becomes low and connectivity is good. Landscapes controlled by human are increasing shapely, such as artificial rivers, irrigation canals, reservoirs, residences, cropland and so natural landscapes are been greatly reduced, especial in desert and Gobi area.
(3) The landscape trends of landscape pattern are equalizing, distribution by human is enhancing, landscape structure is rationalizing, and the regional quality of environment is optimized. While, the whole region is still under a vulnerable ecological environment.
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