摘要
基于MODIS NDVI数据,通过趋势分析、Hurst指数、残差分析等方法,系统分析了2001-2020年三北工程区植被覆盖时空演变特征及气候变化和人类活动对植被的影响。结果表明:1)2001-2020年三北工程区及其各建设区植被NDVI均呈上升趋势,不同分区年增长速率差异明显,黄土高原区>风沙区>东北华北平原区>西北荒漠区。三北工程区NDVI呈现东高西低、南高北低的空间格局。2)研究区改善趋势明显,显著改善趋势面积占45.9%,其中黄土高原区的显著改善面积占比明显高于其他建设区,未来变化以改善为主,但可持续性不强。3)三北工程区植被NDVI与气温、降水均呈正相关关系,人类活动对植被NDVI以促进为主,各土地利用NDVI和残差均表现增加趋势,且趋势具有一致性。4)在植被改善地区和退化地区,人类活动对植被的影响均处于主导地位,人类活动的平均贡献率分别为62.9%和59.06%,不同分区植被对人类活动和气候变化的响应差异明显,其中黄土高原区人类活动对植被改善和退化贡献率最大,分别为75.36%和71.4%。
As an important ecological barrier in our country,the“Three-North Shelterbelt Project”(to build shelter belt in northeast,north,and northwest China)area has a fragile ecological environment.Studies on the temporal and spatial characteristics of vegetation cover can provide support for the ecological construction of the project region.This paper,based on MODIS NDVI data,by adopting methods such as trend analysis,the Hurst exponent,and residual analysis,comprehensively investigated the spatiotemporal evolution characteristics of vegetation cover and the impact of climate change and human activities on the vegetation in the project region from 2001 to 2020.The results showed that 1)from 2001 to 2020,the NDVI of vegetation in the project region and its various construction zones showed an overall increasing trend.There were significant differences in the annual growth rates among different zones,with the Loess Plateau region>wind and sand area>Northeast and North China Plain Region>northwest sesert area.The spatial pattern of NDVI in the project region exhibited a pattern of higher values in the east,lower values in the west,higher values in the south,and lower values in the north.2)The improvement trend in the study area was evident,with significantly improved areas accounting for 45.9%.Among them,the proportion of significantly improved areas in the Loess Plateau region was significantly higher than those in other construction zones.Future changes would be dominated by improvement,but sustainability would not be strong.3)In the project area,the NDVI of vegetation showed a positive correlation with temperature and precipitation.Human activities primarily contributed to the promotion of vegetation NDVI,with increasing trends observed both in NDVI and residuals for various land uses,and the trends were consistent.4)In areas of vegetation improvement and degradation,human activities played a dominant role in influencing vegetation,with average contribution rates of 62.9%and 59.06%,respectively.Different zones showed distinct differences in the response of vegetation to human activities and climate change.In particular,the Loess Plateau region had the highest contribution rates to both vegetation improvement and degradation,accounting for 75.36%and 71.4%,respectively.
作者
夏凯
黄义忠
XIA Kai;HUANG Yizhong(Faculty of Land and Resources Engineering,Kunming University of Science and Technology,Kunming 650021,Yunnan,China)
出处
《西北林学院学报》
北大核心
2025年第1期133-143,共11页
Journal of Northwest Forestry University
基金
国家自然科学基金(41761081)
云南省社科规划办重点项目(ZD202218)。
