Influência do clima nas variações estacionais e interanuais do indice de vegetação de diferença normalizada (NDVI) no montado português

Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia Nowadays the climate change makes more necessary the study of ecosystem dynamics. The Portuguese montado is an ecosystem with very particular characteristics, because is a combined system with pastures and forest, managed by men, and depends on this manage to continue. More than economic value, montado is very important system with a big biodiversity and landscape quality. For this study was propose to study about the seasonal variation of montado, since 2000 to 2012, using remote sensing and vegetation index as tools to analyze the response of montado to different environmental factors, as the precipitation, temperature and relative humidity. The chosen vegetation index was the NDVI (Normalized Difference Vegetation Index), because of all the advantages, and was calculated using MODIS sensor data. To find the relation between our vegetation index vegetation data, and the meteorological variables, was make a time series analysis, and a correlation study of each variable with the vegetation index. The results was satisfactory and was agree with the initial hypotheses. We find that the precipitation is the variable that influences NDVI the most, and this correlation is bigger when we use the accumulative inter-annual and seasonal data instead the original data. The results show the effects of the big drought of 2004 and 2005 too. The remote sensing appears as a very important and critical tool for this study area future and show that this study could be extend with new directions and new research hypotheses