干旱胁迫下雪松土壤水分及生理特性的研究

Study of soil water and physiological characteristics of Cedrus deodara under water stress

通过对雪松根际进行包埋处理,形成干旱土壤环境,研究了干旱胁迫对雪松生理特性的影响.结果表明,5～10月份,土壤干旱胁迫条件下,雪松光合速率平均值较对照降低了55.7%,蒸腾速度降低了46.4%,气孔阻力增大.光合速率和蒸腾速率的最大值出现在6月份,干旱胁迫下分别为18.262μmol·g-1·s-1和9.325mol·g-1·s-1.进入10月份,雪松仍能维持一定水平的光合速率和蒸腾速率.同时,干旱胁迫下,雪松的水分利用效率略有增大,较对照高4.2%,9～10月份,水分利用效率显著增大,10月份较6月份高263%.

The root of Cedrus deodara was wrapped by plastic film,then the dry environment was made.The results showed that photosynthetic rate and transpiration rate was reduced 55.7% and 46.4% than those of control test under soil water stress from May to October,and stomatal resistance increased.The maximum of photosynthetic rate and transpiration rate were 18.226 μmol·g^(-1)·s^(-1) and 9.325 mol·g^(-1)·s^(-1) respectively under water stress,and they appeared in June.The test showed that C.deodara could carry on photosynthesis and transpiration in October.Meanwhile,the water utilization efficiency of C.deodara slightly increased,especialy in September and October,and it increased 263% in October that that of June.