摘要
为了确定UV-B辐射增强和温度变化对高寒草甸植物生理过程的影响,以LI-6400便携式光合测定系统控制温度和紫外灯UV-B辐射增强方法,测定分析了UV-B辐射增强和温度变化对麻花艽（Gentiana stramineaMax-im.）叶片光合作用及相关生理参数的影响。结果显示：麻花艽叶片净光合速率（Pn）、气孔导度（Gs）、胞间CO2浓度（Ci）、蒸腾速率（E）和水分利用效率（WUE）在对照下较高,UV-B辐射为20W和40W处理下较低;8月,Pn在25℃下比15℃下显著高;9月,对照处理下Pn在25℃下比15℃下高。同时,E在25℃比15℃下高;Gs、WUE和Ci在25℃下比15℃下低。另外,麻花艽叶片Pn在光合有效辐射强度为0-800μmol·m^-2·s^-1时随光合有效辐射强度增加而增加幅度较大,800-2200μmol·m^-2·s^-1时增幅较小;Gs和E随光合有效辐射强度增加而增加;Ci在光合有效辐射强度0-800μmol·m^-2·s^-1时随光合有效辐射强度增加而呈现下降趋势,800-3000μmol·m^-2·s^-1变化不大;WUE在光合有效辐射强度0-800μmol·m^-2·s^-1时随光合有效辐射强度增加而呈现增加趋势,800-3000μmol·m^-2·s^-1时呈现下降趋势。说明UV-B辐射增强将对高寒草甸植物-麻花艽叶片光合作用及相关参数将产生极大影响,影响与温度变化有一定的关系。
This study describes the effects of temperature changes and enhanced UV-B radiation on net photosynthesis and related physiological parameter of straw-yellow gentian（Gentiana straminea Maxim.）.Samples were analyzed using 20 W and 40 W UV-B lamps to increase UV-B radiation and with LI-6400 portable photosynthesis systems to change air temperature.Results show that net photosynthetic rate（Pn）,stomata conductance（Gs）,intercellular CO2 concentration（Ci）,transpiration rate（E） and water use efficiency（WUE） of straw-yellow gentian was higher under control than that under 20W or 40 W UV-B lamp treatments,while Pn at 25℃ was higher than that at 15℃ under increasing UV-B radiation treatments in August or under controls in September.Additionally,E of straw-yellow gentian at 25℃ was higher than that at 15℃,while Gs,Ci or WUE of straw-yellow gentian at 25℃ was lower than that at 15℃ under increasing UV-B radiation treatments.Results also show that Pn of straw-yellow gentian increased with increasing photosynthetic active radiation（PAR） when the PAR ranged from 0-800 μmol·m^-2·s^-1hile maximizing when PAR ranged from 800-2200 μmol·m^-2·s^-1ut no change when the PAR ranged from 2200-3000 μmol·m^-2·s^-1he Gs or E of straw-yellow gentian increases with increased the PAR.The Ci of straw-yellow gentian decreases with increased PAR when the PAR ranged from 0-800 μmol·m^-2·s^-1ut did not change when the PAR ranged from 800-3000 μmol·m^-2·s^-1he WUE of straw-yellow gentian increases with increased the PAR when the PAR ranged from 0-800 μmol·m^-2·s^-1nd it decreases slowly when PAR ranged from 800-3000 μmol·m^-2·s^-1esults indicate that enhanced UV-B radiation results in decreased Pn,Gs,Ci,E and WUE of alpine meadows leaves that would be influenced by temperature variation.
出处
《草地学报》
CAS
CSCD
北大核心
2010年第5期622-628,635,共8页
Acta Agrestia Sinica
基金
中国环境科学研究院公益性院所基金项目(2007KYYW05)资助
关键词
UV-B辐射变化
高寒草甸
光合作用
麻花艽
青藏高原
UV-B radiation change
Photosynthesis
Alpine Meadows
Straw-Yellow Gentian
Qinghai-Tibet Plateau
