Abstract:

Throughfall, stem flow and rainfall were measured from Jul. 2009 to Sep. 2010 in an evergreen broad-leaved secondary forest in Yangdongshan, North Guangdong. The characteristics of rainfall and canopy interception of the forest were analyzed. The results indicated that the total rainfall was 2 362.6 mm during the experimental period. Rain days with 0.0-5.0 mm daily rainfall accounted for 55.2% of all rain days, but the rainfall accounted for only 8.0% of the total rainfall. However, rain amount of 10.0-25.0 mm and 25.0-50.0 mm daily rainfall accounted for 35.3% and 29.9% of the total rainfall, respectively. Throughfall, stem flow and interception were 1 837.3, 30.1, and 495.2 mm respectively, and mean throughfall rate, stem flow rate and interception rate were 77.8%, 1.3%, and 21.0% respectively. When rainfall range increased, throughfall rate also increased, but canopy interception decreased. However, with rainfall range increasing, stem flow rate increased firstly and then decreased. During the experimental period, for every rain event, the observed maximum canopy interception was 30.0 mm.

Key words: evergreen broad-leaved secondary forest, canopy interception, hydro-ecological effect, throughfall, stem flow