摘要
采用Li-6400便携式光合仪对共和盆地4个林龄乌柳光合参数进行了对比分析。结果表明,25和37年生乌柳Pn日变化为双峰曲线,出现了光合"午休"现象;4和11年生乌柳Pn日变化为单峰曲线。11和25年生乌柳Pn和Tr日均值显著高于4和37年生乌柳,4年生乌柳WUEt日均值显著高于其它3个林龄乌柳。采用Michaelis-Menten模型对各林龄乌柳光响应和CO2响应参数拟合良好。11年生乌柳α值显著高于其它3个林龄乌柳;4和37年生乌柳Rd值显著高于11和25年生乌柳;11和25年生乌柳Amax值显著高于4和37年生乌柳。叶绿素荧光参数中,11和25年生乌柳ΦPSⅡ、qP日均值显著高于4年生乌柳,4年生乌柳NPQ日均值显著高于其它3个林龄乌柳,37年生乌柳NPQ日均值显著高于11年生乌柳。林龄对乌柳的光合能力产生了显著影响,处于不同生长阶段的乌柳采取了不同的生态适应对策。
An experiment was conducted to study the photosynthetic and fluorescence parameters of Salix cheilophila under field condition using the Li-6400 portable photosynthesis system and PAM-2100 portable fluorescence system in order to find out the differences in photosynthesis of 37-, 25-, 11 - and 4-year-old S. cheilophila in alpine sandy land of Gonghe basin. Resuits revealed that S. cheilophila of four stand ages showed different diurnal courses of gas exchange. The diurnal fluctuations of net photosynthetic rate （ P, ） of 37- and 25-year-old S. cheilophila could be represented by a bimodal curve, indi- cating midday depression of photosynthesis, while those of 11- and 4-year-old S. cheilophila could be diseribed by a unimodal curve. P, and transpiration rate （ Tr） of 11- and 25-year-old S. cheilophila were significantly higher than those of 4- and 37-year-old S. cheilophila, while water use efficiency （ WUEt ） of 4- and 37-year-old S. cheilophila was significantly higher than that of S. cheilophila of other three stand ages. The fitting effects of Miehaelis-Menten equation on the light-response parameters and CO2 response parameters were very well. The initial quantum yield （or） of 1 l-year-old S. cheilophila was significantly higher than that of S. cheilophila of other three stand ages, and photosynthetic capacities （Am,, ） of 11- and 25-year-old S. cheilophila were significantly higher than those of 4- and 37-year-old S. cheilophila, while the dark respiratory rates （ Rd ） were significantly lower than those of 4- and 37-year-old S. cheilophila. Meanwhile, the actual photocbemieal quantum efiieiency （PSll） and photochemical quenching coefficient （qr） of 11- and 25-year-old S. cheilophila were significantly higher than those of 4-year-old S. cheilophila, while the non-photochemical quenching coefficient （NPQ） of 4-year-old S. cheilophila was significantly higher than that of S. cheilophila of other three stand ages. NPQ of 37-year-old Salix cheilophila was significantly higher than that of 11- year-old S. cheilophila. The photosynthetic capacity of S. cheilophila shows significant changes with the increase of stand age, and S. cheilophila of different stand ages in dif- ferent developmental stages adopts various ecological adaptive strategies.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2012年第12期20-26,共7页
Journal of Northeast Forestry University
基金
林业公益性行业科研专项(201204203)
"十二五"国家科技支撑计划项目专题(2012BAD16B0102)
关键词
共和盆地
乌柳
林龄
光合特性
叶绿素荧光
Gongh basin
Salix cheilophila
Stancl ages
Photosynthetic characteristics
Chlorophyll fluorescence
