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选取西北农林科技大学西林校区校园内自然状况下生长良好的耐旱树种刺槐(Robin iap seudoacacia)、元宝枫(A cer truncatum)、沙棘(H ippophae rhamnoid es)、白榆(U lmus pum ila)、油松(P inus tabu laeform is)、白皮松(P inus bungeana)及中生树种女贞(L igustrum lucidum)、柳树(S a lix m atsud ana K o idz.f.pendu la)为研究对象,测定了它们3个季节内的木质部栓塞日变化规律及其与光照强度、大气温度、气孔导度、蒸腾速率等生理生态指标的关系。结果表明:光照强度、大气湿度和大气温度主要是通过对植物气孔运动、蒸腾作用和体内水分关系的调节对木质部栓塞起作用的;木质部栓塞是植物一天生长过程中不可避免的“平常事件”,与植物的光合速率、蒸腾速率、气孔导度和水分利用效率间存在一定的相关关系;它的发生和恢复可能是某些植物适应水分胁迫的一种机制。
Robin iap seudoacacia, Acer truncatum, Hippophae rhamnoid es, U lmus pum ila, which are well-developed under the natural conditions, were selected from the campus of Xilin Campus of Northwest A & F University. Pinus tabu laeformis, Pinus bungeana and Ligustrum lucidum and Willow tree species (Salix m atsud ana K o idz.f.pendu la) The diurnal variation of xylem embolism in three seasons and their relationship with the physiological indexes such as light intensity, atmospheric temperature, stomatal conductance and transpiration rate were studied. The results showed that the light intensity, the atmospheric humidity and the atmospheric temperature mainly affected the xylem embolization through the regulation of the stomatal movement, transpiration and body water. The xylem embolization was an unavoidable “common event” in the plant growth. And plant photosynthetic rate, transpiration rate, stomatal conductance and water use efficiency there is a certain correlation between; its occurrence and recovery may be some plants to adapt to a mechanism of water stress.