【摘 要】
：
利用MODIS的归一化植被指数(NDVI)数据,采用Theil-Sen Median趋势分析、Mann-Kend-all显著性检验方法及Hurst指数法,分析了2000-2017年河西地区植被的变化趋势及其可持续性特
【机 构】
：
兰州大学资源环境学院,兰州730000;兰州大学资源环境学院,兰州730000;兰州大学西部环境教育部重点实验室,兰州730000
论文部分内容阅读
利用MODIS的归一化植被指数(NDVI)数据,采用Theil-Sen Median趋势分析、Mann-Kend-all显著性检验方法及Hurst指数法,分析了2000-2017年河西地区植被的变化趋势及其可持续性特征.结果表明,河西地区2000-2017年NDVI增长区域面积较大且分布广泛,减少区域较少.河西地区植被总体呈稳中向好的趋势,走廊绿洲区植被增长趋势最大,祁连山区植被增长趋势较小,戈壁荒漠区植被变化趋势不显著.植被覆盖持续增长的区域远多于持续降低的区域,但持续增长的能力较弱,小部分处于增长趋势的植被未来发展趋势可能逆转,存在植被退化风险.走廊绿洲区植被持续增长能力最强,祁连山区植被增长持续性较弱,戈壁荒漠区植被较为稳定.
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