Hydrochemical characteristics of throughfall and stemflow in a Moso‐bamboo (Phyllostachys pubescens) forest

Abstract To investigate the impacts of the invasion by bamboo on fluxes of nutrients and pollutants, the nutrient/pollutant fluxes and canopy interactions, including neutralization of acidity, leaching and uptake of nitrogen (N), were characterized in conjunction with rainfall partitioning in a Moso‐bamboo ( Phyllostachys pubescens ) forest. Measurements of precipitation volume, pH, major ions, and silicate (SiO 2 ) in rainfall, throughfall and stemflow were collected weekly in a Moso‐bamboo forest located in Munakata City, Western Japan for 1 year. Results showed that rainfall partitioning into stemflow was larger than that for other types of forest, which may be due to the properties of Moso‐bamboo forest structure, such as a straight and smooth culm. Inorganic N (NO 3 − + NH 4 + ) and S (SO 4 2− ) fluxes of throughfall and stemflow were approximately 1·6 and 1·3 times higher than that of rainfall, respectively. Contribution of stemflow flux to inorganic N and S fluxes to the forest floor was high. This could be due to lower uptake of inorganic N through culm and a higher rainfall partitioning into stemflow than that for other types of forest. The Moso‐bamboo canopy neutralized rainfall acidity, reducing the fluxes of potentially acidifying compounds via throughfall and stemflow. Canopy leaching of K + was distinctly higher than that of Mg 2+ and Ca 2+ and could be related to the high mobility of K + in plant tissues. Cl − and SiO 2 were readily leached as for K + . The impact of the invasion by bamboo on nutrient cycling was discussed. Copyright © 2010 John Wiley & Sons, Ltd.