中国干旱半干旱区2000-2020年土地利用与景观格局演变特征及驱动力分析

Analysis of the Evolution Characteristics and Driving Force of Land Use and Landscape Pattern in 2000-2020 in Arid and Semi-arid Areas in China

中国干旱半干旱区土地利用及景观格局变化对西北干旱区生态维护与经济发展发挥着重要的作用。本文从土地利用变化和景观格局变化两个角度,利用GIS技术和Fragstats4.2软件,对我国2000-2020年干旱半干旱地区的土地利用和景观格局指数进行分析,对21年间的土地利用和景观格局变化模式进行研究,发现:(1)土地利用变化较为显著,且在全时段处于不平衡状态,草地与未利用地双向转换频繁。未利用地面积减少和建设用地面积增加为主要特点,建设用地面积变化幅度最大、动态度最强。(2)我国干旱半干旱区景观在整个研究期间呈现破碎化程度增加、异质性降低、形态日趋复杂的特点(3)土地利用变化深刻影响景观格局,人类活动是土地利用转变的重要驱动因子。人类对该地区土地利用程度的不断提高所造成的景观破碎程度的增加以及该地区景观优势度的直接改变,也从另一个侧面印证了景观格局改变的重要推动因素是人类活动。

Land use and landscape pattern change in arid and semi-arid areas in China plays an important role in ecological maintenance and economic development in the arid and semi-arid areas of China.This paper has two perspectives:land use change and landscape pattern change,i.e.using the GIS and the Fragstats4.2 software to analyze land use and landscape pattern index in arid and semi-arid areas of China in 2000-2020 and study the change mode of land use and landscape pattern in 21 years.The results indicate that:(1)Land use types change significantly in the area,,and the change of land use in the whole period is unbalanced,such as the bidirectional conversion between grassland and unused land is frequent.The decrease of unused land area and the increase of construction land area are the main characteristics,and the change range of construction land use and land use attitude are the largest among the land use types in this research.(2)During the whole study period,the landscape in the arid and semi-arid areas of China showed the characteristics of increasing fragmentation degree,decreasing heterogeneity and increasingly complex shape.(3)Land use change profoundly affects the landscape pattern and human activities are an important driver of land use change.The continuous improvement of human land use degree in the region leads to the increase of landscape fragmentation degree,which directly changes the landscape dominance in the region also confirms that human activity is an important driver of landscape pattern transformation.