台湾地区植被NDVI时空格局演变特征

Evolution characteristics of NDVI spatial and temporal patterns of vegetation in Taiwan

基于1998—2018年SPOT/VEGETATION NDVI卫星遥感数据,结合同期气象资料,采用趋势分析、标准差分析和偏相关系数等数理分析方法,分析了我国台湾地区归一化植被指数(NDVI)的时空变化特征,探讨了NDVI对气候平均态的响应特征。结果表明:时间尺度上,1998—2018年台湾地区植被年际NDVI呈现明显的增加趋势,增速为0.02/10 a;空间尺度上,1998—2018年台湾地区植被改善明显,南北走向的中央山脉地区“绿色植物带”逐年加深;气温和降雨对NDVI的影响存在明显的地域性差异,海拔越高,降雨对植被(林地、草地)的影响越大,在低海拔区域NDVI对气温呈现出显著的负相关关系(P<0.05)。

As an important component of terrestrial ecosystems,vegetation plays an important role in climate regulation,soil and water conservation,and terrestrial carbon balance.Based on the SPOT/VEGETATION NDVI satellite remote sensing data from 1998 to 2018 and the meteorological data of the same period,the temporal and NDVI in Taiwan was analyzed by trend analysis,standard deviation analysis and partial correlation coefficient.The response characteristics of NDVI to the climate mean state were discussed.The results show that the annual NDVI in Taiwan increased significantly from 1998 to 2018,with an increase rate of 0.02/10 a.On the spatial scale,the vegetation improvement in Taiwan was obvious from 1998 to 2018.The"green vegetation belt"in the central mountain area with north-south trend was bettter year by year.For response of NDVI to temperature and rainfall,there was spatial difference.The vegetation(forest and grassland)in high altitude areas,such as central mountains,was more affected by rainfall than by temperature.There was a significant negative correlation(P<0.05)between NDVI and temperature in low altitude and high density human agglomeration areas.Natural disasters occured frequently in the study area and the climate average state affected vegetation growth less in this area.