川藏铁路沿线植被覆盖度时空变化特征分析

基于MODIS-NDVI遥感数据反演了川藏铁路地区2000-2018年植被覆盖度,采用线性回归分析植被覆盖度的时空变化规律,利用相关分析法分析气候、地形等与植被覆盖度的相关关系.结果 表明:(1)2000-2018年川藏铁路沿线平均植被覆盖度为0.629,呈现波动上升趋势,2000-2012年为缓慢增长,2013-20...

Spatial-temporal variation characteristics of vegetation coverage along Sichuan-Tibet railway

Based on MODIS-NDVI remote sensing data,the vegetation coverage long the area of Sichuan-Tibet railway from 2000 to 2018 was inverted.The temporal and spatial variation law of FVC was analyzed by linear regression,and the correlation analysis method was used to analyze the correlation between climate,topography and FVC.The results show that:(1)From 2000 to 2018,the average FVC along the Sichuan-Tibet railway was 0.629,showing a fluctuating rising trend;from 2000 to 2012,it increased slowly;from 2013 to 2018,it increased rapidly.In the 19 years,the proportion of improved FVC was 53.78%,and the proportion of decreased FVC was 5.25%,among which the increase rate was the highest in Kangding to Changdu section,and the decrease rate was the highest in Basu to Linzhi section.(2)The FVC space along the Sichuan-Tibet railway presented a distribution characteristic of high in the east and low in the west.From 2000 to 2018,the average FVC of Chengkang,Kanglin and Lalin railway sections were 0.75,0.61 and 0.55,respectively.The low-altitude areas were dominated by medium and high FVC,while the high-altitude areas were dominated by medium and low FVC.(3)Correlation analysis showed that the vegetation coverage along the Sichuan-Tibet railway was significantly positively correlated with temperature(r²=0.376,P<0.01)and rainfall(r²=0.284,P<0.01).Temperature was the main climatic factor driving the dynamic change of vegetation coverage along the Sichuan-Tibet railway,and it was significantly negatively correlated with altitude(r²=-0.240,P<0.01).