黑河中游土地利用转型过程及其对区域生态质量的影响

干旱区土地利用转型作为影响区域生态系统变化的主要因素,直接关系人类福祉.本文以生态脆弱的黑河中游地区为研究对象,基于1987、2001、2016年的遥感影像数据,采用土地利用转型检测评估模型、生态响应模型系统研究了1987—2016年黑河中游地区土地利用转型的过程及其区域生态质量响应规律.结果表明: 1987—2016年,研究区土地利用转型变化显著,总变化量呈增加趋势,耕地和建设用地持续增加;在随机新增和减少状态下,未利用地向其他地类转型的倾向性不强,草地向耕地转型具有很强的倾向性;研究区生态质量总体呈下降趋势,生态用地呈缩减态势,净减少2.8%,对于生态环境退化影响最大的土地利用转型类型是草地向耕地和未利用地的转型.为促进区域土地资源的可持续利用以及改善区域生态质量状况,需根据区域水资源状况合理分配区域生产用地和生态用地的比例.

Process of land use transition and its impact on regional ecological quality in the Middle Reaches of Heihe River,China

Land use transition is one of the main drivers of regional ecosystem change in arid area, which directly affects human well-being. Based on the satellite images of 1987, 2001 and 2016, the change detection assessment model and ecological response model were used to analyze the process of land use transition and response of ecological quality during 1987-2016 in the ecologically fragile middle reaches of the Heihe River. The results showed that the land use change was significant during 1987-2016 and the total change increased significantly, as well as the continuous increase of the cultivated land and construction land. There was a strong tendency of transform from grassland to cultivated land, while the tendency of transforming unused land to other land classes was not strong under a random process of gain or loss. During 1987-2016, the ecological quality of the study area displayed a decreasing trend as a whole and the ecological land decreased by 2.8%. The land use transition with the greatest impact on the ecological environment degradation was the transition of the grassland to the cultivated land and unused land. Therefore, in order to promote the sustainable use of regional land resources and to improve the regional ecological quality, it is necessary to allocate the proportion of production land and ecological land according to the regional water resources.