1989—2016年吐鲁番高昌区绿洲时空格局变化及其驱动因素

Spatiotemporal Change of the Oasis in Gaochang,Turpan and Its Driving Factors During the Period of 1989-2016

本文以1989、1997、2002、2009、2016年吐鲁番高昌区遥感影像作为数据源,提取高昌近27 a的绿洲分布情况。利用GIS、Fragstats和相关统计方法,开展高昌绿洲时间序列和空间分布上的变化及驱动因素分析。结果表明：27 a来高昌绿洲总体呈扩张趋势,同时绿洲与非绿洲转换现象显著,绿洲面积由1989年的413.47 km^2增长至2016的800.48 km^2,其中1997—2002年扩张速度最快;绿洲面积扩张、缩减主要发生在东西两侧,绿洲稳定区主要集中在绿洲中部,波动变化主要集中在绿洲边缘地区,分布零散地区;绿洲景观格局破碎度先下降后逐渐上升,景观形状趋于复杂,但整体景观结构仍比较单一,易受人类活动影响;27 a来高昌区绿洲变化受自然、人文社会因素的影响,但人文因素起决定作用,其中水资源的开发利用是绿洲扩张的前提条件,农业人口、经济发展、农业现代化和政策是主要的驱动因素。

In this paper,the remote sensing images of Gaochang area in Xinjiang in 1989,1997,2002,2009and 2016 were taken as the data sources to extract the oasis distribution in the study area in recent 27 years.The GIS means,fragstats and related statistical methods were used to investigate the change of time sequence and spatial distribution of the Gaochang Oasis and of the driving factors.The results showed that the Gaochang Oasis was expanded during the study period,the oasis-non-oasis conversion was significant,the oasis area was enlarged from413.47 km^2in 1989 to 800.48 km^2in 2016,and the oasis expansion was the most significant during the period of1997-2002.The central area of the oasis was stable,and the area fluctuation occurred mainly in the eastern and western marginal zones.The fragmentation of the oasis landscape was reduced at first and then increased gradually,the landscape shape was tended to be complex,but the overall landscape structure was still relatively single and easily affected by human activities.In the past 27 years,the oasis change was affected by both the natural and human factors,in which the exploitation and utilization of water resources was the precondition of oasis expansion,and the farming population,economic development,agricultural modernization and policy were the main driving factors.