多情景下的土地利用模拟与特征分析:以武汉市为例

Land use simulation and characteristic analysis in multiple scenarios:a case study in Wuhan

为寻求国土空间最优碳减排路径,实现低碳绿色型国土空间格局优化,以武汉市作为案例区,采用线性规划与Markov模型,形成不同情景下武汉市2035年土地利用结构,将空间自相关效应融入到元胞自动机模型,模拟不同用地结构下的土地利用空间布局,分析未来不同用地结构与空间布局下的碳排放,提出低碳土地利用模式。结果显示:自然发展情景和经济优先情景下,建设用地和耕地面积有明显变动,总碳排放量分别增加8.25%和29.06%;低碳导向情景下,建设用地增速放缓,林地明显增加,总碳排放量增加5.46%。从空间形态上来看,自然发展和经济优先情景下的建设用地围绕中心城区向外扩张态势明显,远城区零散建设用地逐步合并;低碳导向情景下建设用地增加受限,远城区林地增加明显,多生态绿楔和生态廊道的全域生态框架逐步成型。以上结果表明,不同情景下的模拟结果均能表现不同发展策略对武汉市国土空间格局的影响,强调经济效益最大化的经济优先情景碳排放情况不容乐观,融入低碳理念的国土空间开发与保护新格局能够在实现绿色减碳目标的同时兼顾经济增长速度。

Land use change is an important factor that affects the carbon cycle process of terrestrial systems and climate change.In order to seek the optimal carbon emission reduction path for terrestrial space and realize the optimization of low-carbon green national land spatial pattern,this study selected Wuhan as a case study area.Based on linear programming and Markov model,the land use structure of Wuhan in 2035 under different scenarios was formed.The cellular automata model incorporating spatial autocorrelation effect was used to simulate the land use spatial layout based on different land use structures,then the carbon emissions in the future under different land use structures and spatial layouts was analyzed,and finally a low-carbon land use pattern that meets the future development goals of the city was proposed.The results showed that in the natural development scenario and the economic priority scenario,the construction land and cultivated land area will change significantly,and the total carbon emissions will increase by 8.25% and 29.06%,respectively.Under the low-carbon oriented scenario,the growth rate of construction land slowed down,the forest land increased significantly,and the total carbon emissions increased by 5.46%.From the perspective of spatial form,under the natural development scenario and the economic priority scenario,the construction land expands outward around the central urban area obviously,and the scattered construction land in the far urban area was gradually merged.Under the low-carbon oriented scenario,the increase of construction land was limited,the increase of forest land in the far urban area was obvious,and the ecological framework of multi-ecological green wedges and ecological corridors was gradually formed.The above results showed that the simulation results under different scenarios can all show the impact of different development strategies on the territorial spatial pattern of Wuhan.The carbon emissions situation of the economic priority scenario that emphasizes the maximization of economic benefits is not optimistic.The new pattern of national land space development and protection integrated with the low-carbon concept can achieve the goal of green carbon reduction while taking into account the speed of economic growth.