Abstract: The expansion of Phyllostachys edulis into neighbor secondary evergreen broadleaved forest may affect the hydrological functions of litter layers. Using laboratory simulated rainfall experiments and immersion test, we monitored the time of retarding runoff, rainfall interception and water holding capacity of litter between Ph. edulis forest (PEF) and adjacent evergreen broadleaved forest (EBF). When the rainfall intensities were 0.5, 1.0, 1.5 mm·min^-1 and the slopes were 10°, 25°, 40°, the time of litter retarding runoff decreased with the rainfall intensity and the slope, with the time of retarding runoff for PEF being higher than that for EBF. The relationship between interception capacity and rainfall time could be described by N_t=N₀(1-e^-kt) for both stands, and the maximum interception capacity (N₀) of litter layers increased with the rainfall intensity but decreased with the slope. Under the same condition, PEF had higher N₀ than EBF. The maximum water holding capacity rate was 267.51% for PEF, being 9.49% higher than that for EBF (244.33%); the maximum water holding capacity for PEF (7.41 t·hm^-2) was 40.60% higher than that for EBF (5.27 t·hm^-2). These results indicated that the hydrological functions of litter layer may increase with the expansion of Ph. edulis.

Key words: Xinjiang, heavy metal, cotton field., soil quality, physicochemical property