基于GEE的黄河流域植被时空变化及其地形效应研究  

Spatio-temporal Changes of Vegetation in the Yellow River Basin and Related Effect of Landform based on GEE

作　　者：王晓蕾[1,2] 石守海 WANG Xiaolei;SHI Shouhai(School of Geoscience and Technology,Zhengzhou University,Zhengzhou 450000,China;Joint Laboratory of Eco-Meteorology,Zhengzhou University,Chinese Academy of Meteorological Sciences,Zhengzhou University,Zhengzhou 450000,China)

机构地区：[1]郑州大学地球科学与技术学院,郑州450000 [2]郑州大学中国气象科学研究院郑州大学生态气象联合实验室,郑州450000

出　　处：《地球信息科学学报》2022年第6期1087-1098,共12页Journal of Geo-information Science

基　　金：河南省自然科学基金资助项目(212300410292);河南省重点研发与推广专项(科技攻关)项目(212102210137);河南省高等学校重点科研项目(21A420006)。

摘　　要：黄河流域作为中国东部平原的生态屏障,研讨其植被覆盖的时空变化有助于生态环境治理。本文利用GEE平台,基于Landsat数据通过像元二分模型反演了1990—2020年黄河流域植被覆盖度(FVC),并通过Theil-Sen Median趋势分析和Mann-Kendall检验方法剖析FVC的时空变化趋势,挖掘出FVC趋势变化与海拔、坡度、坡向等地形因子之间的响应关系。结果表明:(1)黄河流域FVC整体呈现西北低东南高的空间分布趋势,其中低等FVC占整个流域面积的45%,主要集中于西北部干旱半干旱地区;(2)流域中部植被覆盖改善明显,占整个流域的57.07%,西北部和东南部退化程度相对较高;(3)植被覆盖受地形效应影响较为显著,在坡度大于40°及高程(-31~637 m)时高等级FVC占比较高,坡度8~18°及高程1852~2414 m范围内植被改善效果相对较好。结果可以为黄河流域生态环境保护及高质量发展提供科学支撑。The Yellow River Basin serves as an ecological barrier in the eastern plain of China. Analyzing the spatiotemporal change of vegetation cover in Yellow River Basin and its topographic effects is helpful for ecological environment management. In this study, we first calculated the annual Fractional Vegetation Cover(FVC) of the Yellow River Basin for 1990—2020 through the GEE cloud computing platform using pixel binary model and Landsat images. Then, the spatiotemporal trend of FVC was obtained through Theil-Sen Median trend analysis and Mann-Kendall test. Finally, the topographic effects on FVC was quantified based on Digital Elevation Model(DEM) data(i.e., SRTM Plus) through ArcGIS. The results show that:(1) the FVC in the Yellow River Basin presented a spatial distribution of low in the northwest and high in the southeast. Low-level FVC values accounted for 45% of the entire basin area, which were mainly concentrated in the arid and semiarid areas in the northwest;(2) the vegetation coverage in the middle of the basin was improved significantly,which accounted for 57.07% of the entire region. The degradation trend of the northwest and west region was stronger than that in other regions of the Yellow River Basin;(3) the vegetation coverage was significantly affected by the topography. High-level FVC occurred in regions where the slope was greater than 40° and the elevation was between-31~637 m. The vegetation recovery was good within the range of slope of 8~18° and elevation of 1852~2414 m. The results can provide scientific support for the ecological environment protection and high-quality development of the Yellow River Basin.

关 键 词：黄河流域 植被覆盖度 时空变化 地形效应 Landsat数据 Google Earth Engine 植被指数 定量分析 

分 类 号：Q948[生物学—植物学] P237[天文地球—摄影测量与遥感]