干旱区研究2025，Vol.42Issue(3)：523-533,11.DOI:10.13866/j.azr.2025.03.12
甘南黄河上游植被覆盖度时空变化与地形因子的关系
Relationship between temporal and spatial changes of vegetation coverage and topographic factors in the Upper Yellow River in Gannan
摘要
Abstract
Vegetation cover in the Upper Yellow River in Gannan plays an important role in maintaining the struc-tural stability of the alpine ecosystem and conserving water sources.Exploring the spatiotemporal variation of vegetation cover and its relationship with topographic factors and characterizing the spatiotemporal distribution of vegetation can deepen our understanding of the dynamics and functions of the alpine vegetation ecosystem and provide theoretical support for maintaining ecological balance and restoring vegetation.This paper is based on four periods of Landsat images and Digital Elevation Model data for 1990-2020 at the Upper Yellow River in Gannan,used a pixel dichotomous model,superposition analysis,geographic detector,intensively study the spa-tiotemporal changes of vegetation coverage and the correlation of topographic features in the study area.The re-sults showed the following:(1)From 1990 to 2020,the vegetation coverage in the Upper Yellow River in Gannan experienced a transition from degradation to recovery and then to significant improvement.The area with medi-um and high vegetation coverage(0.6-0.8)constituted the largest proportion,accounting for 77.68%of the total study area.(2)Between 1990 and 2020,the vegetation coverage in the study area showed a significant improve-ment trend.Among them,the area where vegetation coverage improved(Slope>0)accounted for approximately 91.26%of the total area,which was much larger than the area where it declined(Slope<0).(3)There were signifi-cant differences in the explanatory power of the topographic factors for vegetation coverage.Elevation is the main driving factor for vegetation coverage,and the explanatory power of the interaction of topographic factors such as slope,slope direction,and elevation is greater than that of a single factor.(4)Vegetation cover in the study area showed a single-peak pattern of increasing and then decreasing with both elevation and slope;the high-est vegetation cover was found on southerly slopes,while the lowest was on northeasterly slopes.In the time se-ries,the area of vegetation coverage from the north to the southwest shows a shrinking trend,while the areas in the southwest,west and northwest directions are increasing.The results of this study can provide scientific sup-port for ecological protection and high-quality development in the Upper Yellow River in Gannan.关键词
植被覆盖度/地理探测器/时空变化/地形因子/甘南黄河上游Key words
vegetation coverage/geographical detector/space-time changes/topographic factor/the Upper Yel-low River in Gannan引用本文复制引用
张起鹏,路红娥,赵頔琛,卓玛兰草..甘南黄河上游植被覆盖度时空变化与地形因子的关系[J].干旱区研究,2025,42(3):523-533,11.基金项目
国家自然科学基金项目(32060279) （32060279）
