ANALYSIS OF VEGETATION COVERAGE OF GRASSLANDS BASED ON NDVI VALUES. CASE STUDY: POIANA RUSCĂ MOUNTAINS.

In any terrestrial area, but especially in the case of mountainous areas, the spatial distribution of vegetation is conditioned by a series of natural factors such as relief, climatic factors or soils. From another point of view, the distribution of vegetation is different, depending on the phenophases, implicitly on the observation period, during the growing season. In this context, the aim of the work was to analyze the vegetation coverage of the grasslands in the Poiana Rusca Mountains, by applying the Normalized Difference Vegetation Index (NDVI), in five different periods. Five satellite images from the months of March, May, July, August and October were used, on which NDVI was applied, later reclassified according to the obtained values. Quantitatively, the changes produced from one time interval to another were calculated, based on the matrix of transitions, and thus, the changes produced were highlighted. It was found that the highest degree of vegetation coverage of the grasslands was in July, the "peak" of the vegetation season. The application of NDVI for the analysis of vegetation distribution has several advantages: it complements measurements in the field, it is expressed in the form of thematic maps that can be integrated with other geospatial data, it allows the location of "problematic" or risky areas, in terms of vegetation cover.. [ABSTRACT FROM AUTHOR]