Diversity analysis has an increasing importance in the analysis of forest stands, especially in multi-species ones, as a tool to evaluate stand structure and bring to light the differences in stand development through species interactions. The diversity analysis provides more detail to the traditional stand structure descriptions and enables the approach to stand management more consistent not only with the timber production, but also with other productions and values of the multi-benefit forest stands, and/or transformation processes. In literature many diversity measures can be found. The most commonly used are the diversity indices as they allow the quantification of the diversity features. In this study eight diversity indices were used to characterize the horizontal, vertical and spatial distribution of the individuals in multi-species stands, using a series of permanent plots, located in Serra da Lousã, Central Portugal. Diversity dynamics were evaluated with two successive measurements, in 2001 and 2009. The results revealed a tendency towards more diversity with the reduction of the number of maritime pine individuals and the development of other species, mainly sweet chestnut and English oak
