“多目标”需求下扬州市土地利用布局优化

Optimization of land use layout in Yangzhou City for multi-objective demand

建模和情景分析是土地利用变化研究的核心内容,面对城市化进程中日益严峻的生态环境以及粮食安全问题,开展不同约束条件下的土地利用模拟研究对于科学规划和政策制定具有重要意义。以国家级生态示范市扬州市为例,构建耦合景观生态安全格局的CLUE-S模型,结合地类间转变速率调整,模拟预测规划目标年(2030年)不同情景下的用地结构和布局。研究发现:(1)研究区低、中、高安全水平下生态用地面积比例分别为20.68%、36.50%和48.81%;(2)现状发展情景下,城镇及工矿用地量增加明显,用地在原有基础上沿外围呈紧凑连续型扩散,耕地、园林地锐减且分布呈现更加破碎化的状态;(3)耕地保护情景下耕地和园林地分布趋于连片和集中,城镇及工矿用地和交通运输用地对于耕地和生态用地的侵占速率降低;(4)生态涵养情景下园林地面积略有增加,城镇及工矿用地在原有基础上扩张速度减缓,粮食安全和生态安全基本实现。

Modeling and scenario analysis are the core contents of land use change research.Facing the increasingly severely ecological environment and food security problems in the process of urbanization,it is of great significance for scientific planning and policy making to carry out land use simulation research under different constraints.In 2018,with the implementation of the pilot program of"ecological restoration and urban repair"in Yangzhou city,urban construction has become another important direction of ecological governance.By the end of 2018,Yangzhou City had completed high-standard basic farmland,accounting for 73.9%of the city′s farmland,ranking first in northern Jiangsu Province and third in the province.At present,the provincial eco-circular agriculture pilot village project starts to be constructed,and it is more necessary to speed up the ecological transformation of Yangzhou City agriculture in order to ensure the quantity.In this context,it is particularly important to understand the future change trend of land use pattern under different ecological protection requirements.This paper takes Yangzhou City,a national ecological demonstration city,as an example,to construct a CLUE-S model of the coupled landscape ecological security pattern,so as to predict and simulate the land structure and layout under different scenarios in the planning target year(2030).The results showed that:(1)the proportions of ecological land in the study area under low,medium and high safety levels were 20.68%,36.50%and 48.81%,respectively.(2)Under the current development scenario,the urban and industrial and mineral land increased significantly,the arable land and garden land were sharply reduced,and the distribution was more fragmented.(3)Under the scenario of cultivated land protection,the cultivated land tended to be contiguous and concentrated,and the expansion of urban,industrial,mining land and transportation land on cultivated land and ecological land decreased.(4)Under the scenario of ecological conservation,the garden land area increased slightly,the expansion rate of urban and industrial land slowed down,food security and ecological security were basically realized.From the comparison of the three scenarios,it can be shown that in the"ecological conversation"scenario of this research,the prohibition of high ecological security areas can not only realize the"dual security"of ecology and food,but also appropriately guide the economical and intensive development of construction land and achieve high-quality development of social economy.In China,the government vigorously develops ecological civilization construction,attaches importance to ecological protection and cultivated land protection,not only because ecological protection and cultivated land protection is the bottom line of social and economic development,but also because reasonable and orderly ecological protection and cultivated land protection can promote the more efficient development of social and economic.