杂谷脑河流域近30年景观格局时空演变研究

Study on Spatiotemporal Evolution of Landscape Pattern of Zagunao River Basin in Recent 30 Years

杂谷脑河流域是岷江上游典型的干旱河谷区。以1980年和2006年两期Landsat TM遥感影像为主要信息源,从时间序列和空间尺度上分析近30a杂谷脑河流域LUCC过程与景观格局动态变化,揭示其景观格局的时空演变规律,探讨土地利用变化对景观格局的影响机制,以期为其脆弱生境恢复与重建提供依据。结果表明:该流域土地利用变化显著,且以林地大面积减少和灌木林地显著增加为主要特点;区域呈现以自然景观为主,人为景观处于支配地位,以云、冷杉暗针叶林为地带性植被并主导该区域森林景观的格局现状;杂谷脑河流域的景观多样性和均匀度两指数增加,优势度减小,处主导地位的森林景观类型与其它景观类型所占比例的差异在缩小,景观结构趋于均匀,森林景观对流域景观控制作用减弱。

The Zagunao River basin is the typical arid valley of upper reaches of Minjiang River.In this paper,the landsat TM images of 1980and 2006were used as the main information source,the LUCC(land use and cover change)processes and landscape pattern dynamic changes on spatiotemporal of study region in recent30years were analyzed,which aimed to explore the spatial and temporal succession of landscape pattern,to reveal the effect mechanism from LUCC to landscape pattern,and then to provide the basis on restoration and reconstruction of the fragile habitat.The results showed that the land use of study area changed significantly with the main characteristics on area of forestland decreasing and shrub land increasing,the regional present situation was dominated by natural landscape,and the artifical landscape is obvious in ascendancy,meanwhile,the Picea and Abies coniferous forests as the zonal vegetation type controlled the pattern current situation of regional forestland landscape,the index of landscape diversity and evenness increased,while the landscape dominance index decreased,which reflected that different landscape types made up the similar proportion,at the same time,it seemed that the forestland landscape tended to be less controlling on the whole basin landscape.