A study on crown interception with four dominant tree species: A direct measurement

An experiment was conducted to concentrate on the rainfall interception process of individual trees for four common species in Beijing, China, which included needle species (Platycladus orientalis and Pinus tabulaeformis) and broadleaf species (Quercus variabilis and Acer truncatum). Two types of interception storages, the maximum (C_max) and the minimum interception storage (C_min), were examined at four simulated rainfall intensities (from 11.7 to 78.5 mm hr^-1). Results showed that an average of 91% of C_max for all the species was intercepted during the first 10 minutes of rainfall, while 45% of C_max drained off after rainfall cessation. Leaf area index (LAI) and leaf area (LA) were significantly correlated (p < 0.05) with C_max and C_min, while such significant correlations were not found between rainfall intensity and C_max and C_min. Average C_max and C_min across all the species corresponded to 3 and 1% of gross rainfall. Mean C_max and C_min of the needle species were 3.0 and 1.8 times larger than that for the broadleaf ones. Results revealed that interception was a dynamic process which encompassed three phases. In addition, LAI and LA were valid predictors of interception in small trees, and deserve further test in forest stands.