摘要
Landscape morphology can reflect the spatial behavior of land use.Using the Poyang Lake area as an example,the landscape pattern characteristics in 1995,2000,2015,and 2018 are determined by calculating the fractal dimension,fractal stability,patch density,patch shape fragmentation,and landscape isolation,and fractal theory is used to analyze the spatial behavior of land use.The results show that building land was the land use type which consistently had the highest fractal dimension,but the fractal dimension of building land shows a downward trend,indicating that the spatial form of building land gradually developed in an orderly direction under the action of land use spatial behavior.Paddy,dryland,and forested land were the land use types which always had the lowest fractal dimension,and they are in unstable states.The calculation results of patch density,patch shape fragmentation index,and landscape isolation index supported the conclusions of the fractal analysis.One recommendation for realizing the rational layout of the land is to reduce the fractal dimension of building land through scientific and reasonable planning and to guide the orderly development of building land.For natural landscapes such as forested land,shrub forest land,high-coverage grassland,and water area,their fractal dimensions should be increased to reduce human interference and maintain their stability.Finally,the results of this study suggest that the fractal dimension should be introduced into the National Spatial Planning,and used as an index for evaluating the rationality of the regional land use pattern.
土地景观形态能够反映土地利用空间行为特征。在对鄱阳湖地区1995年、2000年、2015年和2018年4个时间点的土地利用现状进行描述的基础上,通过分形维数、分形稳定性、斑块密度、斑块形状破碎度和景观隔离指数分析区域景观格局变化,并运用分形理论对土地利用空间行为进行分析。研究结果显示在1995年到2018年的20多年间,建设用地一直是分形维数最高的土地类型;但从时间尺度上,建设用地的分形维数呈下降趋势,表明建设用地空间形态在土地利用空间行为的作用下逐渐向有序方向发展。水田、旱地和有林地一直是分形维数最低的土地利用类型,且处于景观分形不稳定状态。斑块密度、斑块形状破碎化指数以及景观分离度指数的计算结果支持了分形维数分析的结论。从实现区域土地合理布局的角度,建议通过科学合理的规划,降低区域建设用地的分形维数,引导建设用地有序发展。对于诸如有林地、灌木林地、高覆盖度草地和水域等自然景观,应增加其分形维数以减少人为干扰,维护其稳定性。同时建议在国土空间规划中引入分形维数,将分形维数作为评价区域土地利用格局合理性的一项指标。
基金
The National Natural Science Foundation of China(41961035)
The Natural Science Foundation in Jiangxi Province(20202BAB213014)
The China Postdoctoral Science Foundation(2020M682106)。
