Objective The aim of this study is to determine the differences of stemflow between different forest types and its relationships with diameter at breast height (DBH), and analyze the seasonal variations in stemflow between forest types under the same rainfall levels.

Method Field measurement including standard tree selection and stemflow collection was conducted in three typical forest types located at Baotianman of Funiu Mountain.

Result During the growing season, stemflow volume was positively correlated with DBH under high-level rainfall, but negatively related to DBH under low-level rainfall. Stemflow volume (17770～35590 mL) and stemflow rate (0.106) were greater in winter than spring, summer and autumn under the same rainfall level. There were no differences in stemflow volume among three earlier seasons. Higher stemflow rate was found for conifers-broadleaf mixed forest in autumn and winter, which could be explained by the weakened interception of leaf at canopy in winter. The results showed that mixed coniferous-broadleaf forest had greater stemflow than that of coniferous and broadleaf forest mainly due to its higher stand density and lower DBH.

Conclusion The finding that differential stemflow among forest types associated with rainfall levels and DBH values indicates that DBH and leaf property are critical to determine the seasonal variation in stemflow.