A PRELIMNARY STUDY ON ROOT SYSTEMS OF THE ARTIFICIALLY MIXED STAND OF PINUS TABULAEFORMIS AND QUERCUS VARIBILIS IN XISHAN REGION, BEIJING
Liu Chunjang Guo Xulin Xu Zhenquan
The root systems of pine-oak mixed stand, pure pine stand and pure oak stand were investigated in respect of their morphology, distribution and biomass. The results showed. 1. The fine-root (2 mm in diameter) biomass and thick-root (2-10mm in diameter) biomass were 2440.18kg/ha and 3897.11kg/ha in a 27 years old pure oak stand, 1441.98kg/ha and 1767.93kg/ha in a 28 years old pure pine stand and 1861.65kg/ha and 3323.87kg/ha in the mixed stand of the same age respectively. 2. In the mixed stand both fine and thick root biomasses per oak tree were higher than those in the pure oak stand, and both fine and thick root biomasses per pine tree were lower than those in the pure pine stand. 3. In the mixed stand the distribution of root systems is reasonable and no repe llency between pine roots and oak roots was obserred in the soil.