Presenter : Narayanarao Bhogapurapu
Remote sensing technology in combination with geographic information system (GIS) can render reliable information on vegetation cover. The analysis of spatio – temporal change in vegetation cover and its density has a greater significance in taxonomy and understanding the overall nature of biodiversity with response to recent climatic changes. We analysed the spatio – temporal change and adopted NDVI taxonomy in a micro region like Visakhapatnam district in the north eastern part of Andhra Pradesh state. For this study, Landsat images (TM) of 2011 to 2008 were used. The images were then classified into dense shrubs, less dense shrubs, crop lands / grasslands, built up area, bare surface and water body. Supervised classification was done and maximum likelihood operation was performed to generate vegetation cover maps using QGIS. Afterwards, vegetation cover maps of 2011 to 2009 were crossed to generate the map of change of vegetation. In addition, the use of spectral vegetation index, namely the Normalized Difference Vegetation Index (NDVI) was applied to detect areas of vegetation cover decrease. The study then reveals that vegetation cover of the area has changed significantly during 2011 and 2008.
Keywords: spatio-temporal change, Landsat, NDVI, QGIS, supervised classification.