关键词: 土地利用/覆被类型, 遥感解译, 近期时空变化, 于田绿洲

Abstract: In this paper, based on Landsat TM/ETM+ images of 1991, 2001 and 2011, the spatio-temporal characteristics of land use/cover changes in Yutian oasis were analyzed by using RS and GIS technology. It is found that from 1991 to 2011, cultivated land had decreased 14.41%, most of them had changed to forest and grass land, showing that 20 years adjustment of agricultural structure and reforestation policy had gradually taken effect; water body had increased 64.86%, most of them had came from previous forest, grass land and unused land, which had ensured the rational use of water resources in irrigated oases and to further improved the water infrastructure; forest land had decreased 20.28%, demonstrating that decreasing forest area will undoubtedly impact the local ecological environment, if the ecological functions of forest were ignored; grass land had increased 26.07%, most of them came from arable land, demonstrating that the forest land and unused land, grain for green policies had curbed the destruction of grasslands by blind reclamation, and helped effective increase of grassland area; construction land had increased 440.21%, mainly came from former arable land, forest land and unused land, meaning that the construction area expanded with the population explosion and rapid social and economic development; unused land had decreased 4.75%, mainly changed to decreased arable, grass land and water body, which means blind reclamation was persisted, which severely damaged the natural vegetation cover, made the extremely fragile ecological environment even worse, and because of shortage of water resources, reclaiming had been abandoned.

Key words: land use/cover type, remote sensing interpretation, recent spatio-temporal variation, Yutian Oasis