基于RS和GIS的人工林景观稳定性研究——以常德市桃源县龙潭镇为例

Research on landscape pattern stability of artifi cial forest from perspective of RS and GIS:taking Longtan town of Taoyuan county in Hunan province as an example

以湖南省桃源县龙潭镇人工林为研究对象,利用1994年、2000年、2006年、2010年及2014年5期遥感影像数据,在对研究区人工林景观进行斑块区划的基础上,将每个斑块看作林分中的"单木",斑块之间的边缘效应模拟林分中单木之间的竞争关系,借鉴林分空间结构分析方法,提出了基于斑块边缘效应的人工林景观稳定性分析方法,用于分析斑块、类型和景观不同尺度人工林景观变化规律,运用层次分析法和主成分分析法分别建立类型水平和景观水平的人工林景观稳定性模型,利用提出的人工林景观稳定性分析方法及构建的模型分析了研究区人工林景观的稳定性。结果表明:(1)以松木和杉木为主的人工用材林随着时间的发展,其景观逐步由零星小斑块向阔叶林景观转化,景观破碎化程度有所下降;(2)基于类型水平上的人工林稳定模型反映出斑块类型重要程度前3位依次为阔叶、松木和杉木成熟林,大小分别为0.154 3、0.148 1、0.145 0;(3)在类型水平上,最稳定的年份是2014年,其稳定值为-0.155 1;稳定性最差的年份是2006年,其稳定值为-0.371 8。但在景观水平上2006年则是最为稳定的年份,其稳定值为0.298 7。应用本研究提出的方法分析进一步说明,在类型水平上稳定的景观不一定在景观水平上稳定。

Taking the artificial forest in Longtan town of Taoyuan county in Hunan province as research object, using remote sensing image data of 1994, 2000, 2006, 2010 and 2014 with the division of the artificial landscape in the research area, every forest patch was regarded as ＂individual tree＂ in the forest stand. Besides, this research also used edge effect in the patches to simulate the competitive relationship between individual tree in the forest stand. Meanwhile, drawing on the analysis methods of the forest stand spatial structure, a new analysis methods was be put forward in the paper which could be used to analyze the stability of the artificial landscape pattern based on edge effect between the patches. This method aimed at analyzing the changing law of the artificial landscape concerning different patches, types and views. The Analytic hierarchy process and the Principal component analysis were used to build stability model of the artificial landscape on top of the type level and the landscape level. The paper had analyzed the stability of the artificial landscape pattern in the research area by using the model and the analysis methods mentioned above.The result showed that：（1） Gradually, the landscape of the man-made commercial forest mainly pines and firs had transformed from the little sporadic patches to broad-leaved forest and the phenomenon of landscape fragmentation had decreased to some extent.（2） The stability model of the artificial forest based on type level reflected that the importance of the patches from high to low can be listed as mature broad leaf forest,mature pine forest and mature fir forest with their numerical valued being 0.154 3, 0.148 1 and 0.145 0 respectively.（3） In terms of the type level, the most stable year was the year of 2014 with its stable value being-0.155 1. The least stable year was the year of 2006 with its stable value being-0.371 8. But as for the landscape level, the year of 2006 was the most stable year with its stable value achieving 0.298 7. This method put forward in this paper would be used to further demonstrate that the landscape stable in the type level might not be stable in the landscape level.