Study of Various Vegetational Factors in Buxa Hills of Alipurduar

The vegetation gross primary productivity and carbon sequestration efficiency of vegetation exhibits different spatiotemporal heterogeneity at different spatial and temporal scales, and the sensitivity of carbon sequestration to climate change varies among different vegetation types. This study takes at Buxa hills as an example, and based on remote sensing MODIS images, different vegetation types, gross primary productivity (GPP) and net primary productivity (NPP) were obtained. The carbon utilization efficiency (CUE) values of vegetation were calculated, and the spatiotemporal distribution characteristics of GPP, NPP and CUE of different vegetation types were analyzed. The impact of climate change on vegetation CUE was discussed and the contributions of climate change and human activities to CUE was decomposed. The results showed that GPP showed an increasing trend, while CUE showed a decreasing trend, and the order of GPP size for different vegetation types was: forest>shrub>grassland>cultivated vegetation, the order of CUE size was cultivated vegetation>shrubs>grasslands>forests. GPP was higher in summer, while CUE was higher in spring and winter, and lower in summer. The GPP of different vegetation types shows a increasing trend, with the order of grassland>cultivated vegetation>shrub>forest. While the CUE of different vegetation types shows a decreasing trend, with the order of grassland>shrub>cultivated vegetation>forest. Below an altitude of 700m, there is a larger vegetation CUE, while above an altitude of 1700m, there is a significant increase in vegetation CUE. The vegetation CUE from May to August has the greatest correlation with temperature during the same period, showing negative and positive correlations with temperature and precipitation, respectively. There are differences in different periods, especially in winter vegetation CUE was positively correlated with precipitation and temperature. Meanwhile, human activities also have a certain impact on carbon utilization efficiency. These studies provide a basis for regional vegetation protection and carbon sequestration function assessment.