焦世文 梁靓 陶维新 冯兰君

摘要 [目的]分析甘肃省植被覆盖时空变化特征，为区域生态环境规划提供理论基础。[方法]基于2010—2019年MODIS NDVI产品，结合土地利用、生态功能区划分等数据，采用一元线性回归趋势分析方法和变异系数等分析方法对2010—2019年甘肃省植被覆盖时空分布特征进行阐述，对植被指数变化趋势及变化稳定性进行定量分析。[结果]甘肃省植被指数在年均月尺度上呈现单峰分布，在夏季处于高位，年均NDVI呈现稳步增长的趋势，增速平均为0.003 2/a;植被指数空间分布具有明显的地域差异性，西部地区NDVI值小，可认为基本无植被生长，中东部平原和祁连山地区植被长势较好，NDVI明显较高，南部地区NDVI最高;农业耕作区的植被指数变化波动性比较大，其他地区植被覆盖变化趋于稳定。[结论]基于MODIS NDVI时间序列分析方法可为了解甘肃省土地覆盖状况、开展具有区域差异性的生态保护与修复工程等提供一定的理论依据。

关键词 植被覆盖;NDVI;时空分布;变化特征;遥感

中图分类号 Q948 文献标识码 A

文章编号 0517-6611（2021）09-0070-04

doi：10.3969/j.issn.0517-6611.2021.09.019

Abstract [Objective]To analyze the spatial and temporal variation characteristics of vegetation cover in Gansu Province and provide a theoretical basis for regional ecological environment planning.[Method]Based on MODIS NDVI products during 2010-2019，combined with data of land use and ecological function zone division，the spatial and temporal distribution characteristics of vegetation cover in Gansu Province during 2010-2019 were elaborated by using the analysis methods such as one-dimensional linear regression trend analysis and coefficient of variation，and vegetation index change trends and change stability were quantitatively analyzed.[Result]The vegetation index in Gansu Province showed a single-peaked distribution on the annual average monthly scale，which was at a high level in summer，and the annual average NDVI showed a trend of steady growth with an average growth rate of 0.003 2/a.The spatial distribution of multiple annual average vegetation indices had obvious geographical variability，with small NDVI values in the western region，which could be considered as basically no vegetation growth，and better vegetation growth in the central-eastern plains and Qilian Mountains.NDVI was obviously higher in the central-eastern plains and Qilian Mountains，and NDVI was the highest in the south.The vegetation index changes in agricultural cultivation areas were more volatile，and the vegetation cover changes in other areas tended to be stable.[Conclusion]The MODIS NDVI time-series analysis method can provide some theoretical basis for understanding the land cover status and carrying out ecological protection and restoration projects with regional differences in Gansu Province.

Key words Vegetation cover;NDVI;Spatial and temporal distribution;Variation characteristics;Remote sensing

植被作為土地覆盖最重要的一部分，在全球及区域生态系统环境变化中起着“指示器”的作用[1]。近年来，随着城市发展及人类活动的加剧，植被退化造成的环境问题越来越严重，植被退化及恢复问题受到了各国政府及学术界的关注。及时准确地获取地表植被特征和植被覆盖变化信息，对于揭示地表植被时空变化规律和评价区域生态环境变化具有重要的指导意义;同时，开展植被覆盖变化与气象因子变化之间关系的研究，有助于了解气候变化对生态环境变化的影响，对于加强生态文明建设具有很大的帮助。……