不同土地利用情景下农村景观生态格局优化

景观格局优化是实现有限土地资源优化利用的有效途径。文章以重庆市江津区龙华镇为样区,设置4种不同土地利用情景,通过8个景观格局指数与生态阻力对各情景设置进行分析,在此基础上采用最小累积阻力模型,构建不同景观组分别对4种不同土地利用情景(基准情景、生态情景、发展情景、综合情景)的景观格局进行优化,遴选最佳优化路径。结果表明:样区耕地景观占比最大,这有助于促进景观生态功能的开发与利用;样区较高程度的景观破碎化与较差的景观连通性对景观生态功能的开发与利用产生较大的阻碍作用;比较4种土地利用情景,综合情景的生态源面积大于其它3种情景,且生态源的分布情况也较其它3种情景均匀;在构建生态廊道体系时,综合情景下的物质、能量及物种的流通性也较其它3种情景强;而且,综合情景下的生态节点跟其它3种情景相比,无论是在功能数量上还是在空间分布上,均具有更强的合理性。

THE OPTIMIZATION OF RURAL LANDSCAPE ECOLOGICAL PATTERN OF DIFFERENT LAND USE SCENARIOS: A CASE OF LONGHUA TOWN, JIANGJIN DISTRICT OF CHONGQING

The interrelation between landscape pattern and ecological process is one of the important contents of landscape pattern optimization. And landscape pattern optimization is an effective way to achieve reasonable use of the limited land resource, and can guarantee the coordination and unity of economic benefit, social benefit and ecological environment benefit for land utilization. Taking Longhua town, Jiangjin District of Chongqing as the study site, this paper set four different land use scenarios (e.g., baseline scenario, ecology scenario, development scenario and integration scenario). Every land use scenario was analyzed through landscape pattern index, ecological sensitivity and minimum cumulative resistance. Landscape patterns under four different land use scenario were optimized using the minimum cumulative resistance model to build different landscape compositions with the support of ARCGIS software. The landscape optimization path was selected. The results showed that: The area ratio of cultivated land landscape was the biggest, accounting for 52.47% ofthe study area. This will help to promote the development and utilization of landscape ecological functions. In the study site, the degree of landscape fragmentation was high and landscape connectivity was very poor, which caused a serious negative impact on the development and utilization of landscape ecological function. Comparing of four land use scenarios, the area of ecological source of the integrated scenario was bigger than other three scenarios. And the distribution of ecological resources was also more uniform than other three scenarios. When constructing the ecological corridor system, the circulation of the material, energy and species of the integrated scenario were also stronger than other three scenarios. Moreover, the ecological modes of the integrated scenario were more reasonable than the other three scenarios. Therefore, to optimize the landscape pattern using scene analysis method had the guidance and innovation for the construction of rural landscape ecological pattern. It can present ecological function and value of landscape pattern, and strength the consistency and interaction between the development and utilization of regional land resources and the construction of landscape ecological pattern. This paper will provide scientific basis for regional agricultural development planning and land use planning.