干旱区生态环境知识资源中心

Stemflow is a hydrological flux that largely influences the input of rainwater to the soil and its spatial distribution. Here, we aimed to identify the factors influencing this hydrological flux by quantifying the stemflow of 129 trees in the Brazilian savannah. The attributes of individual trees were investigated as predictor variables influencing either stemflow volume or tree efficiency in generating stemflowproportion of rainfall over the canopy flowing down the stem. The volume of stemflow was higher in trees that were large, had perennial leaves, and exhibited monopodial growth. However, the efficiency of a tree in generating stemflow was negatively correlated to its dimensions. The most efficient trees had a smooth bark surface, monopodial growth, and straight stems. There was large variation in efficiency among individuals, which is related to the high diversity of attributes among the studied trees. The small size of Cerrado trees explains the lower stemflow volume in comparison with trees in forest ecosystems. The efficiency observed in the Cerrado trees was also lower when compared to trees from other ecosystems, even in arid environments. Copyright (c) 2014 John Wiley & Sons, Ltd.