近30年来浏阳河流域景观格局动态及稳定性时空变化特征

Spatial and Temporal Characteristics of Landscape Pattern Dynamics and Stability in Liuyang River Basin in Recent Three Decades

为揭示浏阳河流域的景观稳定性时空变化特征,在RS和GIS技术支持下,利用1985年、2000年和2015年遥感影像获取流域内3期土地利用/覆盖类型数据,运用景观分析方法定量分析了1985—2015年间浏阳河流域景观结构变异特征、稳定性变化特征及景观稳定性与景观类型的相关关系。结果表明:①在1985—2015年间,浏阳河流域景观总体结构的时间变化特征为破碎化度、斑块边缘复杂度和景观多样性先增加后降低,人类干扰强度和景观团聚程度先降低后增加,反映出研究区景观稳定性呈先降低后增加的变化;②该流域的稳定性分布具有明显的空间分异特征,流域东部和南部稳定性较高,中部和西部稳定性较低;③不同景观类型的稳定性高值关联度从大到小的顺序为林地>耕地>人工表面>水体,低值关联度从大到小的顺序为人工表面>耕地>水体>林地;④林地是维持流域景观稳定性的关键景观;⑤社会经济和政策因素是该流域景观稳定性最重要的驱动因素,通过有效的政策调控,可以遏制和改善景观稳定性恶化的状况,为流域的管理和规划提供理论基础和决策依据。

The aim of this study is to reveal the spatial and temporal changes of landscape stability in Liuyang River Basin.Remote sensing images of 1985,2000,and 2015 were used to obtain the land use/cover types of three periods in the basin with the support of remote sensing and GIS technology.Hence,the landscape structure change,landscape stability,as well as the relation between them from 1985 to 2015 were analyzed by landscape analysis method.Research manifested that:1)From 1985 to 2015,the overall landscape structure of Liuyang River Basin was characterized by increased-and-then-decreased fragmentation,patch edge complexity and landscape diversity,as well as human disturbance intensity and landscape aggregation degree in an opposite trend,implying that the landscape stability in the study area weakened but then improved.2)The landscape stability is spatially heterogeneous,high in the east and south of the study area,while low in the middle and west.3)The high-value correlation degree of forest land is the largest,followed by that of cultivated land,artificial surface,and water body in sequence,whereas the low-value correlation degree of artificial surface was the largest,followed by that of cultivated land,water body,and forest land in sequence.4)Forest land is the key landscape to maintain the landscape stability of the basin.5)Social economy and policy are the most important driving factors of landscape stability.The deterioration of landscape stability can be alleviated by effective policy regulation.