温度升高对不同生活型植物光合生理特性的影响

Effects of Enhanced Temperature on the Photosynthetic Characteristics in Different Life-form Plants

为探讨未来温度升高对不同生活型植物的影响,选取了华南地区常见且分布较广的11种木本植物、7种草本植物和3种藤本植物为研究对象,通过人工模拟温度升高(20、25、30、35℃)的实验方法研究其光响应曲线及特征参数。结果表明,木本植物中大叶相思(Acacia auriculaeformis)、无患子(Sapindus mulorossi)、樟树(Cinnamomum camphora)罗汉松(Podocarpus macrophyllus)、降香黄檀(Dalbergia odorifera)和马樱丹(Lantana camara)的光合生理指标在不同温度下差异均不显著;麻楝(Chukrasia tabularis)的光补偿点(LCP)和气孔导度(Gs)随着温度升高而升高;火力楠(Michelia macclurei)和海南蒲桃(Syzygium cumini)的胞间CO2浓度(Ci)随着温度的升高而下降;海南石梓(Gmelina hainanensis)的Gs和Ci均随着温度升高而下降,其最大净光合速率(Pmax)在不同温度下差异不显著;凤凰木(Delonix regia)的Pmax和Gs随着温度升高而升高,在30℃达到最大。草本植物中,香根草(Vetiveria zizanioides)、华南毛蕨(Cyclosorus parasiticus)、马齿苋(Portulaca oleracea)的光饱和点(LSP)、LCP、Pmax、Ci在不同温度下均差异不显著,Gs随着温度的升高而增大;飞扬草(Euphorbia hirta)、升马唐(Digitaroa ciliaris)、中华结缕草(Zoysia sinica)的Pmax和Gs随着温度升高而增大。金钟藤(Merremia boisiana)、薇甘菊(Mikania micrantha)和厚叶悬钩子(Rubus crassifolius)的Pmax、Gs随着温度的升高而增大,在30℃时达到最大值;LCP随着温度的升高而增大;LSP在不同的温度下无显著性差异。厚叶悬钩子的Ci在不同温度下无显著性差异;金钟藤的Ci随着温度升高而增大,在30℃达到最大值;薇甘菊的Ci和温度呈正相关。与木本和草本植物相比,温度升高对藤本植物的Pmax、Gs、LCP和Ci促进作用更为显著。

To explore the effects of enhanced temperature onthe photosynthetic characteristics in different life-form plants, we chose 11 woody plants, 7 herbaceous plants and 3 vines in South China and measured their characteristic parameters of the light response curves under four temperature levels (20, 25, 30 and 35℃). We found no significant difference in the photosynthetic characteristics for most of the woody plants among the different temperatures, such asAcacia auriculaeformis,Sapindus mulorossi,Cinnamomum camphora,Podocarpus macrophyllus,Dalbergia odorifera andLantana camara. The light compensation point (LCP) and stomatal conductance (Gs) ofChukrasia tabulariswere raised, while the intercellular CO2 concentrations (Ci) ofMichelia macclurei and Syzygium cumini were decreased with rising temperature. As the temperature was increased,Gs andCiofGmelina hainanensiswere decreased while the maximum net photosynthetic rate (Pmax) showed no significant difference.Pmax andGs of Delonix regia increased with increasing temperature until 30℃. Under different temperatures, there was no significant difference for light saturation point (LSP), LCP, Pmax andCi of some herbaceous plants, such asVetiveria zizanioides,Cyclosorus parasiticusand Portulaca oleracea, exceptGs elevated with raising temperatures.Pmax andGs of other herbaceous plants, such asWedelia trilobata, Digitaroa ciliaris, Euphor bia hirta andZoysia sinica, were elevated with raising temperatures, while their LCP showed a reserved trend. For all three vines, such asMerremia boisiana, Mikania micranthaandRubus crassifolius,LCP,Pmax,Gs andCi increased with increasing temperatures. Additionally, compared with woody and herbaceous plants, the rising temperatures performed more promotion effects on the photosynthetic characteristics of vines.