ESTIMATING MACROPORE AND MATRIX FLOW USING THE HYDROGRAPH SEPARATION PROCEDURE IN AN EXPERIMENTAL FOREST PLOT

This study was conducted to estimate macropore space, macropore flow a nd matrix flow in an experimental forest plot in the Ouachita Mountain s of Arkansas. Lateral soil water fluxes and soil capillary potentials were observed in the isolated plot during applied rainfall experiment s. Rainfalls were applied 17 times during the period 17 July to 10 Oct ober 1991. The subsurface hydrograph separation technique was used to estimate macropore space, macropore flux and matrix flux. The boundary between macropore and matrix Row was statistically determined by cova riance analysis. The maximum estimated lateral macropore space was app roximately 0.006 (cm(3) c(-3)). The maximum estimated lateral macropor e and matrix flow were 0.042 and 0.00066 cm s(-1), respectively. This report also emphasizes the need for further research on the hydrograph separation procedure for estimating macropores and macropore flow.