This study investigated the floristic similarity of the tree component of 39 upper montane forest fragments in Atlantic domain, Brazil, and the influence of geographic and climatic variables on the patterns observed. It was created a binary matrix of presence and absence of the tree species compiled from the 39 floristic and phytosociological survey. For the relationship of the floristic composition of the areas with the environmental and spatial variables, the geographic coordinates and climate data of each area were extracted. The floristic similarity of the fragments was measured using a dendrogram and for determination of environmental and spatial variables influence on floristic patterns, a nonmetric multidimensional scaling analysis (NMDS) was used. The dendrogram analysis and the NMDS showed the formation of clusters, predominantly among fragments located in the same phytogeographic unit. The existence of an environmental gradient based on the climatic conditions was observed. In areas with higher thermal seasonality, annual temperature range, precipitation, latitude and longitude, upper montane forests with rain forest matrix occurred, and in areas with higher average temperature, daily temperature range, isothermality, seasonality of precipitation and minimum temperature in the coldest month, upper montane forests with seasonal matrix occurred.
Phytogeography; Floristic comparison; NMDS
