摘要
基于MODIS-NDVI遥感数据、气象数据和植被类型数据,结合趋势分析、变异系数和地理探测器等方法,分析内蒙古高原2000-2020年荒漠草原、落叶栎林、草甸草原、典型草原和灌木、禾草半荒漠5种植被类型NDVI的变化特征及其与气象因子的关系,利用残差分析法分离人类活动的影响。结果表明:2000-2020年,内蒙古高原区域平均NDVI呈上升趋势,平均增长速率为0.013·10a^(-1),其中落叶栎林NDVI增速最快(0.032·10a^(-1)),灌木、禾草半荒漠增速最慢(0.009·10a^(-1)),空间上呈由西向东梯度式升高的带状分布。过去21a,研究区内植被改善面积占总面积的91.59%,低波动和中低波动面积占研究区总面积的89.75%;草甸草原退化较为严重,退化面积占该植被类型总面积的13.63%,其他4种植被类型改善面积占各自植被类型总面积的比例均达90%以上。不同植被类型NDVI和全区NDVI均与降水量显著相关,气象因子间的双因子增强或非线性增强交互作用明显,水热共同作用是影响高原全区NDVI的主导因素。21a来研究区人类活动的影响不断增强,且对高原植被NDVI有促进作用,5种植被类型中人类活动增强面积占各自植被类型总面积的比例均达70%以上。
Based on MODIS−NDVI remote sensing data,meteorological data and vegetation type data,combining trend analysis,coefficient of variation and geographic detector,the variation characteristics of NDVI in five vegetation types of desert grassland,deciduous oak forest,meadow grassland,typical grassland and shrubs-grasses semi-desert in the Inner Mongolia Plateau from 2000 to 2020 and its relationship with meteorological factors were analyzed,while the human activities effects on NDVI of different vegetation types were separated using residual analysis.The results show that from 2000 to 2020,the regional average NDVI of Inner Mongolia Plateau showed an increasing trend,with an average growth rate of 0.013·10y^(-1),with a spatially graded band distribution from west to east.The NDVI of deciduous oak forests increased the fastest(0.032·10y^(-)1),while that of shrubs-grassy semi-deserts increased the slowest(0.009·10y^(-1)).The proportion of improved vegetation in the study area to total area of the study area was 91.59%,and the proportion of low and medium-low fluctuation area to the total area of study area was 89.75%.But the meadow grassland was more seriously degraded,and the proportion of degraded area to the total area of this vegetation type was 13.63%,while the proportion of improved vegetation in the other four vegetation types to the total area of their respective vegetation types was over 90%.Both NDVI of different vegetation types and the whole plateau were most strongly correlated with precipitation,and the two-factor enhancement or non-linear enhancement interaction between meteorological factors was obvious,with the combined effect of water and heat being the dominant factor influencing the whole plateau NDVI.The impact of human activities in the study area over the past 21 years had been increasing and contributed to NDVI of the plateau vegetation,with the proportion of the enhanced area of human activities in each of the five vegetation types reaching over 70% of the total area of the respective vegetation types.
作者
吴运力
张钰
田佳榕
WU Yun-li;ZHANG Yu;TIAN Jia-rong(Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University/College of Forestry,Nanjing Forestry University,Nanjing 210037,China)
出处
《中国农业气象》
CSCD
北大核心
2023年第12期1155-1168,共14页
Chinese Journal of Agrometeorology
基金
江苏省研究生科研与实践创新计划项目(KYCX19_1096)。