Abstract:

Transpiration rate (E) and stomatal conductance (gs) in leaf of Acacia mangium were measured in a subtropical low hilly area of Guangdong Province, South China. Results showed that E and gs had a similar daily variation, both exhibiting a bimodal pattern in summer, and single-peak pattern in winter. The highest average E was found in summer, and the lowest in winter: E in winter was just 27.6 % of that in summer. The water consumption through transpiration of the A. mangium forest showed a clear difference between drought and wet seasons. Annual water consumption through transpiration was calculated as 1625. 1mm, which accounted for 78.3% of precipitation during the same period. The result indicated that water consumption through transpiration of A. mangium forest could approach that of a tropical rainforest.

Key words: Acacia mangium, Transpiration rate, Stomatal conductance, Water ecology