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对塔克拉玛干沙漠南缘策勒绿洲前沿地区多枝柽柳 (Tamarixramosissima)进行了研究 ,生长季节和灌溉前后水分关系的特征表明 :多枝柽柳在生长季节保持了较高较稳定的清晨水势 ,植物能够平衡白天水分损失造成的水分亏缺 ,水分恢复状况良好。环境气候变化对渗透势等水分参数的影响不及植物水分恢复状况对它们的影响。除了个别数据 ,多枝柽柳水势和渗透势的降低幅度很小 ,更像是生长过程的结果 ,植物水分胁迫的特征并不明显。对比水分生理上对干旱胁迫的适应———渗透势的迅速降低和质外体水含量的增加 ,膨压消失点相对含水量(RWCp)和渗透势差值 (ΔΠ)等参数显示的生理特征表明 ,植物更加依靠稳定充足的水分供应来适应生长环境中极端的高水压差和与此相应的高大气蒸发要求。与此适应 ,植物和地下水发生了联系 ,并且一次性灌溉对植物水分状况的恢复基本没有帮助 ,保持地下水位稳定在根系的可吸收范围内成为保护绿洲前沿多枝柽柳长期存在的关键。多枝柽柳的水分特征属于中生植物的范畴 ,对极端环境的适应属于躲避的类型。
Tamarix ramosissima was studied in the frontier of the Cele oasis on the southern margin of the Taklamakan Desert. The characteristics of the growth season and the relationship of water before and after irrigation show that the tamarix ramosissima maintains a relatively high and stable early morning water potential in the growing season, and the plant can balance Water loss caused by moisture loss during the day, water recovery in good condition. The effects of climate change on the soil moisture parameters such as the soil osmotic potential are less than those of the plant water restoration. With the exception of individual data, the decrease in water potential and osmotic potential of T. ramosissima is much smaller, more like the result of the growth process, and the characteristics of plant water stress are not significant. Compared with the physiological adaptation to drought stress, the physiology characteristics of drought stress, such as the rapid decrease of osmotic potential, the increase of water content of apoplast, the relative water content of turgor disappearance point (RWCp) and the difference of osmotic potential (ΔΠ) Suggests that plants rely more on a stable and adequate supply of water to accommodate the extreme high water pressure differences in the growing environment and the corresponding high atmospheric evaporation requirements. With this adaptation, plants and groundwater contact, and a one-time irrigation on the water status of plants recovered little help to maintain the groundwater level within the root resorbable within the protection of the forefront of oak Tamarix willow long-term key. The water characteristics of Tamarix ramosissima belong to the category of mesophytes, and the adaptation to extreme environment belongs to the type of avoidance.