Chapter 3 - Analyzing seasonal variation in the vegetation cover using NDVI and rainfall in the dry deciduous forest region of Eastern India

Abstract

Ecological viability of the environment has been crucially dependent on the vegetation status of the region across the globe. Climate parameters, namely, rainfall, temperature, relative humidity, evapotranspiration, etc., play essential roles in maintaining the health of the vegetation. Thus analyzing the influence of climate parameters on vegetation is essential to maintain their potentiality and sustainability. In the present study the relationship between rainfall and vegetation status was analyzed in Bankura district of West Bengal. Rainfall data from 1901 to 2018 has been collected from six stations located in the study area using CRU and Swat datasets. Trend-Free Pre-whitening (TFPW) Mann–Kendall (MK) and Sen's slope test were employed in the RStudio to examine the rainfall variability at different stations. Normalized difference vegetation indexes (NDVI) for different seasons were prepared from Landsat 8 OLI data of 2019. The association between NDVI and TFPW-MK values of rainfall was analyzed through regression to assess the influence of rainfall on vegetation. Results indicated a strong increasing trend in rainfall at an annual scale as well as during monsoonal months and post-monsoonal months. Neither a decreasing nor an increasing trend in rainfall was observed during the summer and winter seasons. Significant variability in vegetation was also identified from the seasonal analysis while a relationship was identified between rainfall and vegetation status indicating the influence of rainfall on vegetation in the study area. The approach used here will be instructive for formulating effective management strategies for planning in the forest-dominated region at various scales.