清香木对不同土壤水分胁迫的生长和光合响应

以1年生清香木实生苗为试验材料，通过设置2种土壤极端水分条件与5种不同程度土壤水分胁迫处理，研究不同土壤水分胁迫对苗木地径、株高、生物量、净光合速率、胞间CO2浓度、蒸腾速率等光合指标变化。结果表明，（1）苗木的成活率、地径、苗高等指标随着水分胁迫（干旱）的加深而呈现递减趋势；（2）苗木净光合速率、气孔导度、蒸腾速率及瞬时羧化效率与胁迫程度成反比，而胞间CO2浓度和瞬时水分利用效率与胁迫程度成正比；（3）清香木幼苗具有一定程度的抗旱能力，恢复能力较强，可作为喀斯特山区植被恢复和群落构建的先锋树种。

Response of Different Soil Water Stress on Growth and Photosynthetic in Pistacia weinmannifolia Seedlings

After selecting 1-year-old Pistacia weinmannifolia seedlings as experimental materials , setting 2 ex-tremes and 5 different water stress gradients , researching on the effects of water stress on seedling basal diameter , plant height , biomass , and net photosynthetic rate of photosynthesis was conducted , and the results showed that：1 ） Survival rate , diameter , and seedling height showed a descending tendency with the increasing moisture stress （drought）;2） The net photosynthetic rate （Pn）, the stomatal conductance （Gs）, the transpiration rate （Tr） and the instantaneous carboxylation efficiency （ CE ） had negative relation with the water stress level of the seed-lings, the intercellular CO2 concentration （Ci） and the instantaneous water use efficiency （WUE） had positive re-lation with water stress degree; 3） Seedlings of P.weinmannifolia had some anti-drought capacity with strong resil-ience, and it could be pioneer tree species for vegetation recovery in Karst areas.