摘要
为了掌握岩溶生态环境下典型植物的水分生理生态特征,采用英国产TPS-1便携式光合作用测定系统,研究比较了桂林毛村不同地质背景(石灰岩、白云岩和砂页岩)下黄荆(VitexnegundoLinn.)的蒸腾光合和水分利用效率特征,并通过偏相关分析和主成分分析,探讨了影响黄荆水分利用效率的主要因素。结果表明,①砂页岩区黄荆的日平均蒸腾速率明显高于石灰岩区和白云岩区,但日平均光合速率却明显低于石灰岩区,与白云岩区差别不显著。关于水分利用效率(WUE),则是石灰岩区远高于砂页岩区,白云岩区则略高于砂页岩区,说明生长在岩溶区(石灰岩区和白云岩区)的典型植物黄荆在长期的演化中形成了适应岩溶干旱的水分生态特征。②影响黄荆水分利用效率的主要因子是大气温度、大气相对湿度、气孔导度和CO2浓度,但影响程度因地质背景的不同而有较大差异。
In order to grasp the characteristics of water physiological ecology of typical plants in the karst ecosystems, the compara- tive study on photosynthesis, transpiration and water use efficiency （WUE） of 14tex negundo Linn. under different geological background （limestone, dolomite and sandstone） were carried out in Maocun, Guilin, using a portable TPS-1 Photosynthesis System made in England. The main influencing factors of water use efficiency（WUE） of Vitex negundo were also explored through partial correla- tion analysis and principal component analysis. The results were obtained as follows： （1） The average diurnal transpiration rate of 14tex negundo in sandstone area was significantly higher than that in limestone area and dolomite area, but the average diurnal pho- tosynthesis rate of Vitex negundo in sandstone area was significantly lower than that in limestone area while had no significant difference with that in dolomite area. The water use efficiency （WUE） of 14tex negundo in limestone area was much higher than that in sandstone area, while the WUE of 14tex negundo in dolomite area was a little higher than that in sandstone area. These results suggested that, in the long-term evolution, the typical plant Vitex negundo grown in the karst areas （limestone area and dolomite area） formed water ecological characteristics to adapt to karst drought. （2） The main factors influencing the WUE of Vitex negundo were air temperature, air humidity, stomatal conductance and CO2 concentration, but the influencing degree varied obviously with the geological background.
出处
《生态环境》
CSCD
北大核心
2008年第3期1100-1106,共7页
Ecology and Environmnet
基金
国家自然科学基金青年基金项目(40302034)
