Incident Precipitation Partitioning: Throughfall, Stemflow and Canopy Interception in Eucalyptus dunnii Stand

Abstract

Atmospheric deposition is responsible for the ions input, which may be due to dust and aerosols and rainfall. During rainfall a portion is intercepted by the tree canopy and returned to the atmosphere by evapotranspiration, another part crosses the forest canopy called throughfall and stemflow. The objective of the study was to quantify incident rainfall partitioning into throughfall, stemflow and canopy interception in a Eucalyptus dunnii stand in southern Brazil. Four plots of 20 m × 21 m were demarcated. The rainfall consists 3 rain collectors in an open area. The throughfall consisted 3 collectors per plot in the line, interlining and diagonal positions of the trees. The stemflow consisted in the installation of three systems per plot formed by a hose in the trunk of the tree that leads the solution to a reservoir. The adjustment of the throughfall, stemflow and canopy interception in function of the incident precipitation was of 99%, 90% and 52%. As the volume of rainfall increases, the coefficient of variation decreases. The annual rainfall was 1903 mm, with a canopy interception average of 8.9%.