丝绸之路经济带城市景观格局变化分析——以阿克苏市主城区为例

Analysis on landscape pattern changes in the Silk Road Economic Belt:A case study of the main urban area of Aksu city

以阿克苏市主城区为例,以景观生态学理论为指导,应用GIS和RS技术手段,研究探讨了阿克苏市城市景观格局特征及其演变过程。结果表明,阿克苏市建设用地面积和耕地面积整体呈递增趋势,未利用地和水体面积呈递减趋势,而林地总面积的变化具有不稳定性,呈先递增后递减趋势。在景观要素变化幅度与变化速度方面,1989—2018年建设用地的变化幅度最大,变化速度最快,水体的变化幅度与变化速度其次,林地、耕地和未利用地的变化幅度与变化速度较稳定。这表明近30年间阿克苏市主城区建设用地面积扩张以未利用地和林地面积转换为基础使城市面积不断扩张,导致城市对水资源需求的增高,使得研究区水体面积呈递减趋势。从研究区景观水平来看,1989—2018年,斑块数量(NP)和斑块密度(PD)呈递增趋势,分离度指数(SPLIT)均先增后减,香农多样性指数(SHDI)和香农均匀度指数(SHEI)呈逐渐增加的趋势,表明阿克苏市城市发展进程中景观异质性和破碎化程度在增高,景观斑块丰富度增高,这意味着人类经济活动的影响越来越大。

Taking the main urban area of Aksu city as an example,the characteristics of Aksu city’s urban landscape pattern and evo⁃lution process were studied and discussed with the guidance of landscape ecology theory and the application of GIS and RS technology.The results showed that,the constructed land area and cultivated land area in Aksu city showed an increasing trend,while the unused land area and water area showed a decreasing trend,and the change of the total forest area was unstable,showing an increasing trend and then decreasing trend.In terms of the change range and change speed of landscape elements,construction land had the largest change range and the fastest change speed from 1989 to 2018;water area had the second change range and change speed;forest land,cultivated land and unused land had relatively stable change range and change speed.It shows that,in the past 30 years,the Aksu city’s expansion of construction land area is based on the conversion of unused land and forest land,which leads to the continuous ex⁃pansion of urban area and the increase of urban demand for water resources,making the water area of the research area show a decreas⁃ing trend.From the point of the study area landscape level,in 1989—2018,the number of patches(NP)and patch density(PD)showed increasing trend,separating degree index(SPLIT)first increased and then reduced,Shannon diversity index(SHDI)and Shannon evenness index(SHEI)showed a trend of increasing,indicating that in the process of urban development,the degree of land⁃scape heterogeneity and fragmentation in Aksu city increased,landscape patch richness increased,this means that the impact of hu⁃man economic activity is more and more bigger.