2001-2018年贵州省NDVI时空演变及其对气候变化和人类活动的响应

Spatio-temporal Variation in NDVI and Its Response to Climate Change and Human Activities in Guizhou Province During 2001-2018

[目的]研究贵州省植被覆盖对气候变化和人类活动的响应程度,为区域生态环境建设提供理论依据。[方法]选取2001-2018年MODIS13 A1影像,结合气象数据,利用线性趋势分析、偏相关分析和残差分析等方法,分析了贵州省18年间NDVI的时空变化特征,探究了NDVI对气候变化的响应规律以及人类活动对NDVI的影响。[结果]①2001-2018年贵州省NDVI呈现显著上升趋势,增长速率为0.0053/a,空间上极显著增加和显著增加区域面积分别占研究区域的52.80%和16.80%。②2001-2018年贵州省气候向暖湿方向发展,NDVI与气温和降水呈正相关关系,且NDVI对气温的敏感性高于降水。③月尺度上NDVI对气温的响应不存在滞后性,对降水响应存在一个月滞后性;NDVI与气候月尺度相关性高于年尺度。④人类活动对贵州省植被覆盖作用日益增强,对NDVI贡献度为72.30%。[结论]人类活动对NDVI的影响大于气候变化,贵州省植被变化是气候变化和人类活动共同作用的结果。

[Objective]The response of vegetation coverage to climate change and human activities in Guizhou Province was studied to provide important guidance for restoring the regional ecological environment.[Methods]Based on MODIS13 A1 data and meteorological data,the spatio-temporal variation in the normalized difference vegetation index(NDVI)during 2001-2018 in Guizhou Province was analyzed.Moreover,the impact of climate change and human activities on the NDVI was explored with linear trend analysis,partial correlation,and residual methods.[Results]①The NDVI showed a significant upward trend at a growth rate of 0.0053 per year in Guizhou Province during 2001-2018.In the space studied,the extremely significant and the significant improvement areas accounted for 52.80%and 16.80%of the study area,respectively.②The climate showed a process of distinct warming and increasing humidity in Guizhou Province during 2001-2018.The NDVI was positively correlated with temperature and precipitation,and the NDVI was more sensitive to temperature than to precipitation.③There was no lag in the response of NDVI changes to temperature on a monthly scale,but there was a one-month lag in the response to precipitation.The correlation between the NDVI and climate change on a monthly scale was higher than that on an annual scale.④The effect of human activities on vegetation coverage was increasing in Guizhou Province,and the contribution to the NDVI was 72.30%.[Conclusion]The impact of human activities on the NDVI was greater than that of climate change.The spatio-temporal variation in the NDVI was the result of the combined effects of climate change and human activities in Guizhou Province.