Print PageResults/Conclusions :
Low-intensity rainfall events (i.e., 5.0 and 9.9 mm) increased water content in the litter and at 0 – 80 cm soil depth, but the increased soil water content was lost in several days. Moisture recharge with intermediate rainfall (around 15 mm) lasted longer. High-intensity rainfall events (i.e., 28.3 mm) increased soil water content up to 85% in 0 – 40 cm soil layers and could recharge the groundwater. Following the light rainfall in early spring, the δD of water from the litter, humus, illuvial and material layers decreased first and then gradually reached the pre-rainfall level with the changes delayed in material layer. In summer, influence of intermediate rainfall on δD of water reached to the litter humus, and illuvial soil profile, but not hit material layer. Heavy rainfall (28.3 mm) affected δD of water in all layers. The δD of soil interflow slightly fluctuated with rainfall events. The δD of shallow groundwater did not differ significantly among all the rainfall events. In growing season, rainfalls with intermediate intensities temporally altered the shape of δD profile curve of soil water in the upper layer of soil following the rainfall events. In contrast, high-intensity rainfall greatly affected the shape of δD profile curve of soil water in all soil layers. Following a heavy rainfall, the preferential flow initially occurred through macropores, decayed plant roots, and rocks at different depths of soil profile. With continuing rainfall, the litter and surface soil were near saturated or saturated, and the infiltration process became homogeneous and plug-like. Forest soil water, particularly in deeper soil profile, was slightly affected by rainfall events and thus can be a source of water supply for regional needs, particularly during dry seasons.
