摘要
在100%、70%、40%和10%4种光照条件下,对刺龙牙生长及光合特性进行研究,结果表明:刺龙牙移栽苗的地径当年生长量和2年生播种苗地径均表现出70%>100%>40%>10%,苗高生长随光照强度的增加而增加。100%和70%光照条件下,苗高生长差异不显著;整形修剪后,70%光照条件下,侧枝平均基径以及径高比最大,促成侧枝形成的比率最高,达86.7%,也能形成二级侧枝,侧枝表现出矮壮的特征,能为商品芽的生长发育提供充足的营养供应,提高商品芽的质量;刺龙牙的净光合速率日变化规律在不同光照条件下均为单峰型曲线,100%光照条件下,净光合速率在8:00时出现高峰,其他光照条件下在10:00出现高峰,比100%光照条件下推迟2 h,以后开始下降。70%光照条件下净光合速率日最大值为12.93μmol.m-2.s-1,比100%光照条件下日最大值高0.66μmol.m-2.s-1。刺龙牙随光照强度的减少,净光合速率降低。因此,在生产上人工栽植刺龙牙可结合在其它树种全光造林时进行混交栽植,或在林分郁闭度较低(透光70%左右)的林下栽植,提高光合产量,从而提高刺龙牙的商品芽产量和质量。
An experiment was conducted to study the growth and photosynthetic characteristics of Aralia elata （Miq.） Seem under four shading levels （100%, 70%, 40% and 10% of full light）. Results indicate that the diameter increments of root collar of 1-year-old transplants and 2-year-old seedlings reduce with light intensity decreasing. Height increment rises with light intensity increasing, and no significant differences were found between 70% of full light and full light. The basal diameter of lateral branches and the ratio of diameter to height （ 86.7% ） of the seedlings after shaping are the highest under 70% of full light treatment, and the seedlings produce stocky secondary lateral branches, which provide enough nutrition to the development of commercial buds and improve the quality of the commercial buds. The daily variation of net photosynthetic rate presents a unimodal curve. The peak occurs at about 8：00 a.m. under 100% of full light condition, while the peak occurs at about 10：00 a.m. under other light intensity conditions. The net photosynthetic rate is 12.93 μmol·m^-2·s^-1 under 70% of full light condition, which is 0.66 μmol·m^-2·s^-1 higher than that under full light. Therefore, Aralia elata could be planted with other species or under low forest coverage in order to improve the yield and quality of commercial buds.
出处
《东北林业大学学报》
CAS
CSCD
北大核心
2008年第1期23-25,共3页
Journal of Northeast Forestry University
基金
国家"十一五"林业科技支撑计划课题(2006BAD03A04)
辽宁省重大科技攻关项目(2006207002)
关键词
遮荫
刺龙牙
整形修剪
生长
光合特性
Shading
Aralia elata （ Miq. ） Seem
Shaping
Growth
Photosynthetic characteristics
