高寒地区2种白刺光合生理参数与土壤含水量关系

摘要

To compare the adaptability of Nitraria tangutorum and N.sibirica in cold and arid region, one-year old potted seedlings of 2 Nitraria species were used as research subject , and the photosynthetic and physiological pa-rameters such as net photosynthetic rate ( Pn) , transpiration rate ( Tr) and water use efficiency ( WUE) of differ-ent soil moisture contents were analyzed.The results showed that in alpine region in Qinghai, N.tangutorum and N.sibirica reach the maximum net photosynthetic rate in 21.92 % and 17.67 % soil moisture and the maximum transpiration rate in 17.72 %and 17.55 %.The soil moisture to maintain well water use efficiency was 11.85 %and 13.31%.It showed that N.tangutorum was more suitably grow in relatively high water conditions region, and under drought condition N.sibirica had better survival ability.%为比较唐古特白刺和小果白刺在高寒干旱地区的适生性，以1年生2种白刺的盘栽苗为研究对象，对＜7.5％、7.6％～12.5％、12.6％～17.5％等6种土壤水分含量条件下唐古特白刺和小果白刺叶片净光合速率、蒸腾速率、水分利用效率等光合生理参数进行测定分析。结果表明，在青海高寒地区，唐古特白刺和小果白刺分别在21.92％和17.67％的土壤含水量时，达到最大净光合速率；在土壤含水量为17.72％和17.55％时，具有最大蒸腾速率；2种白刺能够维持较高水分利用效率的土壤含水量分别是11.85％和13.31％。说明唐古特白刺适宜在水分条件相对较高的区域生长，而小果白刺在干旱缺水的条件下生存能力更强。