Diversidade funcional em sistemas de montado : fluxo de nutrientes em Quercus rotundifolia Lam . Functional diversity in “ montado ” systems : nutrients fluxes in Quercus

Nutrient cycling in Quercus rotundifolia Lam. systems, regarding precipitation was studied at Évora (Southern Portugal), since November of 1996 until December of 2000. The amounts of gross rainfall, throughfall (at different distances from the tree trunk) and stemflow were measured continuously and samples for chemical analysis were collected weekly. The concentration of nutrients was higher in the throughfall than in the gross rainfall, especially in the areas closer to the tree trunk. Nutrients transferred to soil, through bulk rainfall, throughfall and stemflow were quantified. The highest concentration of nutrients was observed in the stemflow water. Soil physical and chemical characteristics, underneath and outside Quercus rotundifolia crowns, were studied in areas where trees commonly are wide spaced. The amounts of the forest floor litter layer were also evaluated. Soil physical and chemical characteristics showed in general a positive effect with tree presence. Nitrogen transformation was examined under and outside the influence of the tree canopies. Nitrogen availability was higher in the soil of under crowns areas.