基于土地利用变化的祁连山地区生境质量时空演变分析

Analysis on Spatio-temporal Evolution of Habitat Quality in Qilian Mountains Based on Land Use Change

[目的]对祁连山地区的生境质量和生境退化状况开展研究,揭示人类活动对该地区生态环境的影响程度,为该地区的生态环境保护和发展提供科学参考。[方法]基于1970s末以来全国1∶10万土地利用数据,分析1970s末至2015年近35 a来祁连山地区的土地利用和景观格局变化特征,并采用InVEST模型评估该地区生境质量变化。[结果]①草地和未利用土地是该区最主要的土地利用类型,其次是林地、耕地、水域、城乡工矿居民用地;其中草地和城乡工矿居民用地的变化较剧烈,前者先减后增,后者持续增加。②在时间变化上,随着土地利用类型的变化,该区的生境质量由恶化的态势逐渐趋于改善,2015年生境质量最好。③在空间分布上,该区的生境质量和生境退化度均表现为东高西低。[结论]优越的自然条件使其生境质量较高;人类活动强度较高则是生境退化度较高的原因。

[Objective]The habitat quality and habitat degradation in the Qilian Mountains was explored,in order to reveal the extent of human activities affecting the ecological environment of the Qilian Mountains and to provide scientific references for the ecological environmental protection and development in the region.[Methods]The land use and landscape pattern changes in the Qilian Mountains in the past 35 years based on the national 1∶100000 land use data since 1970s,and then the InVEST model was used to evaluate the evolution in habitat quality.[Results]①Grassland and unused land were the most important land use types in the study area,followed by forest land,cultivated land,waters,urban and rural construction land.Among them,changes of grassland and urban and rural construction land were more severe,the former was reduced firstly and then increased,while the latter continued to increase.②In temporal scale,with the change of land use type,the habitat quality of Qilian Mountain area gradually improved from the deterioration,and the habitat quality was the best in 2015.③At spatial scale,both of the habitat quality and habitat degradation degree in the Qilian Mountains were high in the east and low in the west.[Conclusion]Superior natural conditions result in higher habitat quality,and higher intensity of human activities are responsible for habitat degradation.