This study aimed at comparing the distribution, abundance and size of Drosera montana in microhabitats under different conditions of soil humidity and vegetation cover in Serra do Cipó, state of Minas Gerais. In a transect of 15x3m, all individuals of D. montana were mapped and their diameters were measured. We calculated the aggregation indexes of Clark & Evans and of Hopkins. The transect was divided into 45 quadrats of lm². Soil samples were collected in each quadrat for moisture content determination. The percentage of vegetation cover was estimated for each quadrat using the method of Daumbemirre. D. montana presented an aggregated pattern of distribution. A higher abundance of individuals was observed on sites with intermediate soil humidity and vegetation cover, in a continuum of environmental conditions varying from sites with dry soils and low vegetation cover to sites with wet soils and high vegetation cover. However, the size of D. montana was apparently not affected by soil humidity or vegetation cover, and is probably determined by prey trapping success. These results suggest that the aggregated pattern observed for this species is related to water and light availability, but its growth is possibly influenced by an interaction of biotic and abiotic factors.
plant-soil relation; aggregation; spatial distribution; carnivorous plant; Serra do Cipó