高寒地区2种白刺光合生理参数与土壤含水量关系

The Relationship between Photosynthetic Physiological Parameters and Soil Moisture Content of 2 Nitraria Species in Alpine Region

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。

To compare the adaptability of Nitraria tangutorum and N. po^ed seedlings of 2 Nitraria species were used as research subject, sibirica in cold and arid region, one-year old 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.