基于RS和GIS的张掖市土地利用景观格局变化及驱动力

Driving forces and changes in landscape pattern of land utilization based on RS and GIS in Zhangye city,Gansu province

以张掖市2000,2005年Landsat TM影像为源数据,运用景观生态学方法研究土地利用景观格局动态变化,并从自然和人文角度探讨驱动力.结果表明:研究区呈现以草地景观为基质,未利用土地、林地和耕地景观为主体的交错分布格局;各类景观均有变化,2005年草地景观面积21 189.12 km^2,较2000年下降1.39%,林地3818.13 km^2,较2000年增加11.40%,未利用土地景观面积和缀块数增加明显;自然条件是土地利用景观格局变化的前提,指导人类对区域土地利用;人文因素是主因,表现为黑河分水政策、区域人口增长和人地矛盾加剧,主导景观类型的改变.在社会经济发展的同时,对土地利用和开发应做到科学合理.

The space-time changes in landscape pattern of land utilization were studied in terms of Landsat TM data during 2000 and 2005 based on GIS and RS. The principle and technique of landscape ecology were used to study the landscape pattern changes, and the driving forces behind land utilization in Zhangye were discussed in terms of natural and human factors. The results show that the grassland is the matrix of the study area, the mixed grassland landscape pattern is composed of grassland and relative principal parts of unused land, woodland and arable land. Different landscape types changed to different extents, in 2005, the area of grassland was 21 189.12 km^2, a decline of 1.39% than in 2000, and the woodland was 3 818.13 km^2, an increase of 11.40%. The area and patch number of unused land changed obviously. Natural environment was the basic condition for landscape pattern of land utilization, and the land cover pattern directed human actions in land utilization and the human factors were the guiding factor for the changes in land use, which could be directly shown in the water redistribution around the Heihe river, the conflict between the increasing population and land use. With the support of economic development and planning principles for land utilization, the sustainable utilization and development of land could be realized by rational development and land conservation in the study area.