基于GIS分析的西北地区土地利用与景观格局演变研究——以甘肃省兰州市为例

Study on the Evolution of Land Use and Landscape Pattern in Northwest China Based on GIS——Taking Lanzhou City of Gansu Province as an Example

以西北地区重点城市兰州为研究对象,借助ENVI和GIS软件对兰州市1990、2000、2010年及2018年遥感影像图进行解译处理,得到兰州市4期土地利用型图。在此基础上进一步运用Fragstats及SPSS软件,进行类型变化、动态度、转移情况、相关性及景观格局指数分析,探寻其变化情况及影响因素。结果显示:(1)1990—2018年间,研究区土地利用和景观格局发生了明显变化,耕地、草地等自然景观利用类型面积逐年减少,建筑用地等人工景观利用类型面积则逐年增加;(2)驱动因素分析表明人为驱动因素GDP与城镇化率等是驱动土地利用变化的主要因素,总体变化与城市化的加快密切相关;(3)景观指数分析表明,人工景观的无限制扩张,导致整体景观向破碎化发展,景观复杂程度增加,斑块逐渐趋于分散。综上分析认为,兰州市的土地利用与景观格局状况在28年间趋于复杂,城市化发展是造成土地利用和景观格局向人工发生演变的重要因素。兰州市需要贯彻可持续发展理念,结合自身优势进行绿色生态农业及水域建设。

Taking Lanzhou,a key city in Northwest China,as the research object,using ENVI and GIS software,the remote sensing images of Lanzhou in 1990,2000,2010 and 2018 were interpreted to obtain the four phases of land use type map of Lanzhou.On this basis,Fragstats and SPSS software were further used to analyze the type change,dynamic degree,transfer situation,correlation and landscape pattern index to explore its change trend and influencing factors.The results showed that:(1)From 1990 to 2018,the land use and landscape pattern in the study area changed significantly.The area of cultivated land,grassland and other natural landscape types decreased year by year,while the area of construction land and other artificial landscape types increased year by year.(2)The analysis of driving factors shows that human driving factors such as GDP and urbanization rate are the main driving factors of land use change,and the overall change is closely related to the acceleration of urbanization.(3)The analysis of landscape index shows that the unlimited expansion of artificial landscape leads to the fragmentation of the whole landscape,the increase of landscape complexity,and the gradual dispersion of patches.In conclusion,the situation of land use and landscape pattern in Lanzhou has become more complex in the past 28 years.Urbanization is an important factor causes the natural and artificial evolution of land use and landscape pattern.Lanzhou needs to implement the concept of sustainable development and carry out green ecological agriculture and water area construction in combination with its own advantages.