常绿阔叶林两种树种幼苗对不同光环境的适应--关于生长特征和光合色素含量的研究  

Adaptation to Different Light Regimes of Two Tree Species in Evergreen Broad-Leaved Forests——Growth Characteristics and Pigment Contents in Seedlings Gordonia acuminate and Sloanea leptocaa

作　　者：汤爱仪[1] 陶建平[1] 刘欣[1] 严超龙[1] 梁琴[1] 

机构地区：[1]西南大学三峡库区生态环境教育部重点实验室,西南大学重庆市三峡库区植物生态与资源重点实验室,西南大学生命科学学院,重庆400715

出　　处：《西南大学学报（自然科学版）》2008年第1期109-113,共5页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(30371141);西南师范大学博士基金项目

摘　　要：在旷地（相对光强100%）、林窗（18%～23%）、林下（3%～7%）3种自然光环境下,通过比较缙云山亚热带常绿阔叶林演替前期种四川大头茶（Gordonia acuminate）和顶级种薄果猴欢喜（Sloanea leptocarpa）的幼苗生长、生物量和光合色素含量,探讨不同生态习性亚热带常绿阔叶树种幼苗对光环境的适应及响应的异同.结果表明：1）在旷地环境,两种幼苗具有低的比茎长（SSL）、单位鲜重叶绿素（ChlM）、单位面积叶绿素（ChlA）、单位鲜重类胡萝卜素（CarM）和高的类胡萝卜素/叶绿素（Car/Chl）以适应高光环境.与四川大头茶相比,薄果猴欢喜具有高的茎生物量比（SMR）、Car/Chl和低的SSL、叶生物量比LMR（p〈0.05）;2）在林下环境,两种幼苗具有高的比叶面积（SLA）、叶面积比（LAR）、ChlM、ChlA、CarM和低的Chl a/b以适应低光环境.与四川大头茶相比,薄果猴欢喜具有更大的SLA,LAR,ChlM,ChlA,CarM和更低的Chl a/b（p〈0.05）.上述结果表明：早期种四川大头茶适应旷地光环境的能力略强于顶级种薄果猴欢喜,但适应林下的能力较差.两种幼苗对光适应能力的差异一定程度上可以解释它们在常绿阔叶林中不同的演替地位.Growth characteristics, biomass and pigment contents in seedlings of two species in subtropical evergreen broad-leaved forest, Gordonia acuminate （early-successional species） and Sloanea leptocarpa （late-successional species）, were compared to study their adaptation to different light regimes. They were grown in different light regimes： open land（relative light intensity 100%）, gap （18-23%） and understory （3-7%）. Both species showed good adaptation to the high growth light regimes （open land） in this study, as they were low in specific stem length （SSL）, chlorophyll contents（ChllM, ChlA） and CarM, and high in carrotenoid/chlorophyll（Car/Chl）. Compared with G. acuminate, S. leptocarpa had higher values of stem mass ratio（SMR） and carrotenoid/chlorophyll（Car/Chl）, and lower specific stem length（SSL）, leaf mass ratio（LMR） on the open land （p〈0. 05）. In contrast, in the understory, they were high in specific leaf area （SLA）, leaf area ratio （LAR）, chlorophyll contents （ChllM and ChlA） and CarM and low in Chlorophyll a/ b （Chl a/b） in the understory. Compared with G. acuminate, S. leptocarpa had higher values of SLA, LAR, ChlM, ChlA and CarM,and lower values of Chlorophyll a/ b （Chl a/b） （p〈0. 05）. These results indicated that G. acuminate acclimated better to the open land but did worse to the understory environment, as compared with S. leptocarpa. Their abilities to acclimate light regimes might explain their successional status in subtropical evergreen broad-leaved forests.

关 键 词：幼苗 光环境 生长特征 生物量分配策略 光合色素 

分 类 号：Q914.29[天文地球—古生物学与地层学]