© 2003 Heron Publishing—Victoria, Canada
Explanation of vegetation succession in subtropical southern China based on ecophysiological characteristics of plant species
Qiong Gao (1, 2), Shaolin Peng (3), Ping Zhao (3), Xiaoping Zeng (3), Xian Cai (3), Mei Yu (4), Weijun Shen (3) and Yinghui Liu (1)
1. MOE Key Lab of Environmental Change and Natural Disasters, Institute of Resources Science, Beijing Normal University, Beijing
100875, P.R. China / 2. Author to whom correspondence should be addressed (gaoq@bnu.edu.cn) / 3. South China Institute of Botany, Chinese Academy of Sciences, Guangzhou 510650, P.R. China / 4. Institute of Botany, Chinese Academy of Sciences, Beijing 100093, P.R. China / Received July 31, 2002; accepted December 30, 2002; published online May 15, 2003
Summary
A stomatal conductance model and a photosynthesis model were applied to field measurements of transpiration and photosynthesis
of seven tree species growing in subtropical southern China. Parameter values of drought resistance and tolerance and biochemical
assimilation capacity were obtained by means of nonlinear statistical regression, and were used to quantify species succession.
The analysis indicated that the models adequately described the ecophysiological behavior of the trees under various environmental
conditions. We found a general pattern of decreased drought resistance and tolerance, but increased biochemical assimilation
capacity from pines to heliophilus broadleaf trees to mesophilus broadleaf trees. Succession was explained on the basis of
these physiological characteristics together with positive feedbacks caused by changes in soil physical properties. The ecophysiological
explanation of succession implies that: (1) fitness of a species for a particular succession stage at a particular location
can be measured by stomatal behavior and biochemical assimilation capacity under local climate and soil conditions; (2) selection
of species for a particular location at a particular succession stage can be guided by the parameter values provided in this
study; and (3) succession may be accelerated by selecting trees with large root systems and large soil–root conductances that
facilitate soil hydraulic redistribution of water.
Keywords:
assimilation, model, photosynthesis, stomatal conductance.
