Assessment of space and time changes of NDVI (biomass) in Armenia's mountain ecosystems using remote sensing data

Abstract

This study of vegetation biomass for different areas in the mountain ecosystems of Armenia was implemented for the vegetation period of 2013. The research was done based on time series of Normalized Difference Vegetation Index (NDVI) as NDVI images have been proven to be a powerful tool to monitor biomass growth during the last decade. NDVI, which can be directly calculated from Landsat satellite data, is related to vegetation canopy characteristics. This NDVI-based research of different-aspect slopes at 1850-3150 m have indicated that during vegetation period the highest biomass is detected on north facing slopes at altitudes of 2300-2400 m, and the lowest-on south facing slopes at altitudes of 2000-2100 m. High correlation coefficients between NDVI values of southwest slopes and absolute altitudes of localities are detected in April and August, whereas variation in NDVI values depending on the altitude is nonlinear.