摘要
木荷(Schima superba)作为中国亚热带常绿阔叶林的重要组成树种,在2008年南方冰雪灾害中受到严重损害。本研究在浙江江郎山随机设置5个400m2样地,并将受害木荷分为断木和倒木2种类型,研究不同部位萌枝光响应、气体交换以及叶绿素荧光参数等光合生理特征,有助于人们对群落更新机理的认识,为研究亚热带地区萌枝生态学特征提供理论依据。结果表明:不同叶龄之间,2年生叶片的最大净光合速率(Pmax)、最大光化学效率(Fv/Fm)、PS的潜在活性(Fv/F0)、有效光化学效率(Fv'/Fm')、比叶重(LMA)、叶片全氮含量大于1年生叶片,其总叶绿素含量(Chl(a+b))显著高于1年生叶片(P<0.05),而叶绿素a/b(Chl(a/b))低于1年生叶片;不同部位之间,Fv/Fm、Fv/F0、Fv'/Fm'、Chl(a+b)、Chla/b、类胡萝卜素(Car)表现为断木的中部和倒木的根部最高;LMA、全氮含量表现为断木顶部>中部>根部,倒木根部>中部>顶部;不同受害类型木荷之间,倒木萌枝净光合速率(Pn)、水分利用率(WUE)高于断木(P<0.05),而断木萌枝对光有更宽的生态辐,其光补偿点(LCP)低于倒木,光饱和点(LSP)却高于倒木。
Schima superba,an important tree species of China subtropical evergreen broadleaf forests,suffered from the ice and snow disaster in 2008.In this study,five 400 m2 plots were randomly established in Jianglangshan Mountain of Zhejiang Province,and the damaged S.superba trees were classified into decapitated and uprooted.The photosynthetic responses,gas-exchange,and chlorophyll fluorescence parameters of the sprouts at different segments were studied,aimed to understand the mechanisms of the community regeneration after the extreme disturbance and to provide a theoretical basis for the study of sprout ecology in subtropical regions.As for the different age-class leaves,2-year-old leaves had the higher maximum net photosynthetic rate（Pmax）,maximal photochemical efficiency of PSⅡ（Fv/Fm）,potential activity of PSⅡ（Fv/F0）,effective photochemical efficiency of PSⅡ（Fv＇/Fm＇）,leaf mass per area（LMA）,and nitrogen（N） content than 1-year-old leaves.2-year-old leaves also had a significantly higher chlorophyll（a＋b） content than 1-year-old leaves（p0.05）,but the chlorophyll a/b ratio was lower than that of 1-year-old leaves.For the sprouts at different segments,the sprouts at the middle segment of decapitated trees and at the basal segment of uprooted trees had the highest Fv/Fm,Fv/F0,Fv＇/Fm＇,Chl（a＋b）,Chla/b,and carotenoids（Car）.The sprouts at the top segment of decapitated trees had the highest LMA and N content,followed by those at middle segment,and at basal segment.For uprooted trees,the LMA and N content exhibited an opposite order,i.e.,basal segment middle segment top segment,and the net photosynthetic rate（Pn） and water use efficiency（WUE） were significantly higher than those of decapitated trees（P0.05）.Decapitated trees had broader ecological amplitude to sunlight,with lower light compensation point（LCP） and higher light saturation point（LSP） than uprooted trees.
出处
《生态学杂志》
CAS
CSCD
北大核心
2011年第12期2753-2760,共8页
Chinese Journal of Ecology
基金
林业公益性行业科研专项(201104006和201104008)
中国林业科学研究院中央级公益性科研院所基本科研业务费重点项目(CAFYBB2008006)资助
关键词
冰雪灾害
光合作用
叶绿素荧光参数
叶龄
部位
ice and snow disaster
photosynthesis
chlorophyll fluorescence parameter
leaf age
segment.
