摘要
叶片中叶绿素含量在光合作用中的光吸收、传递和转换过程中起到重要作用。为了预测未来大气CO2浓度升高并伴随温度上升的情况下,植物在不同的氮素营养水平下光合能力的变化,做了在3种氮素水平下(15 mmol.L-1N,7.5 mmol.L-1N和不施氮)CO2倍增和温度升高4℃对蒙古栎一年生幼苗叶片中叶绿素含量的影响的实验。结果表明:氮素水平对叶绿素含量影响显著,在CO2倍增(700μmol.mol-1)、高温(+4℃)和正常温度、大气CO2浓度条件下,高氮素水平下的叶绿素含量明显高于正常氮素水平和不施氮;CO2浓度和温度对叶绿素含量的影响受到氮素的制约:在高氮的条件下CO2浓度倍增促进叶绿素a、b的合成,而且对叶绿素b合成的促进尤为显著;而温度升高4℃能够促进叶绿素a的合成,但是对叶绿素b含量的影响不显著。在正常氮素条件下叶绿素a、叶绿素b及总量各个处理间的差异均不显著;在不施氮的条件下,CO2倍增和升高适当的温度在一定的程度上可以促进叶绿素a的合成,不能同时保证叶绿素b的合成。CO2浓度升高明显导致蒙古栎幼苗对氮素水平的需求也增加,高温条件下的蒙古栎幼苗也在一定程度上增加了对氮素的需求。
Chlorophyll content in leaves plays an important role in light absorption, transfer and transformation in photosynthesis. In order to predict the photosynthetic capacity of the plant under different nitrogen levels with elevated CO2 concentration and temperature in the future, we carried out the experiment about the chlorophyll content of one year old Q. mongolica seedlings exposed to double CO2 concentration, elevated temperature and control under different nitrogen levels. The results showed that ni- trogen levels significantly affected chlorophyll content. Under the three treatments of double CO2 concentration, elevated temperature and control, the chlorophyll content of high nitrogen was obviously higher than normal nitrogen level and no nitrogen added. The effect of CO2 concentration and temperature on chlorophyll content were also limited by nitrogen levels： under high nitrogen, CO2 concentration accelerated the chlorophyll a component and more significantly accelerated chlorophyll b component. And elevated temperature（ ＋4℃ ） could increased chlorophyll a content, but didn＇t affect chlorophyll b content. Under normal nitrogen level, chlorophyll a, b and total content were not affected by CO2 concentration and temperature. Under no nitrogen added, double CO2 concentration and elevated temperature to some extent might improve chlorophyll a content, but couldn＇t synthesize chlorophyll b at the same time. Elevated CO2 concentration significantly resulted in more requirements of Q. mongolica seedlings to nitrogen, and the seedlings under elevated temperature also to some extent needed more nitrogen.
出处
《植物研究》
CAS
CSCD
北大核心
2006年第3期337-341,共5页
Bulletin of Botanical Research
基金
国家自然科学基金资助项目(No.30471372)
关键词
叶绿素含量
CO2倍增
高温
氮
chlorophyll content
double CO2
elevated temperature
nitrogen
