Altera？？o da Diversidade de Espécies Arbóreas nos Povoamentos Florestais entre 1995 e 2005 (Portugal Continental)

percentage of basal area was used to evaluate tree species diversity in forest stands from 1995 and 2005 national forest inventories sample plots. the analysis was carried out at the prof region level (forest management regional plans) and statistical chi-square test was performed to verify if the changes occurred between 1995 and 2005 in the distribution of the number of tree species per sample plot were significant. eight prof regions show significant changes. for each of those regions, we illustrate forest composition and the diversity changes are outlined by the evaluation of hill series for 1995 and 2005.