不同光环境下栓皮栎和刺槐叶片光合光响应模拟  

Simulation on photosynthetic light-responses of leaves of Quercus variabilis and Robinia pseudoacacia under different light conditions

作　　者：李理渊 李俊[2] 同小娟[1] 孟平[3] 张劲松[3] 张静茹 LI Li-yuan;LI Jun;TONG Xiao-juan;MENG Ping;ZHANG Jin-song;ZHANG Jing-ru(College of Forestry,Beijing Forestry University,Beijing 100083,China;Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Belting 100101,China;State Forestry Administration Key Laboratory of Tree Breeding and Cultivation,Research Institute of Forestry,Chinese Academy of Forestry,Beijing 100091,China）.)

机构地区：[1]北京林业大学林学院,北京100083 [2]中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室,北京100101 [3]中国林业科学研究院林业研究所国家林业局林木培育重点实验室,北京100091

出　　处：《应用生态学报》2018年第7期2295-2306,共12页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(31570617;31100322);中央高校基本科研业务费专项资金项目(YX2011-19)资助~~

摘　　要：植物的光合作用在一定程度上能够体现其对生境的响应情况.采用Li-6400XT光合测定系统,测定了黄河小浪底森林生态系统定位研究站栓皮栎和刺槐人工林林内、林缘叶片气体交换的光响应曲线,利用叶子飘模型对光合作用-光响应进行了拟合,分析了林内和林缘光合参数的差异,将气孔导度机理模型与光合作用-光响应修正模型进行耦合,研究了气孔导度(g_s)的光响应特征.结果表明:7—8月,当光强小于200μmol·m^(-2)·s^(-1)时,林内栓皮栎叶片净光合速率(P_n)高于林缘叶片,初始量子效率(α)高于林缘叶片12.4%,林内栓皮栎叶片对弱光的捕获和利用能力明显高于林缘叶片;当光强大于200μmol·m^(-2)·s^(-1)时,林缘栓皮栎叶片光合能力P_n高于林内.低光强下(0~200μmol·m^(-2)·s^(-1)),林内刺槐叶片P_n高于林缘;当光强大于200μmol·m^(-2)·s^(-1)时,林内刺槐叶片P_n低于林缘,且暗呼吸速率(R_d)和光补偿点(I_c)分别低于林缘50.0%和42.8%,以此来减少碳损耗,适应较低的光合速率.林内和林缘刺槐g_s随光强的变化差异显著.栓皮栎和刺槐叶片对不同光环境具有较强的适应能力.栓皮栎叶片的最大净光合速率(P_(n max))和α主要受气孔导度控制,R_d和I_c主要受气温影响.刺槐叶片的P_(n max)和α均与气温呈显著正相关,I_c、光饱和点(I_s)与叶片饱和水汽压差呈显著正相关.Photosynthesis can reflect the responses of plants to environmental changes.In this study,photosynthetic light-response curves were measured by the Li-6400XT photosynthetic system in Quercus variabilis and Robinia pseudoacacia plantations in Xiaolangdi Forest Ecosystem Research Station.Photosynthetic light-response curves were fitted by Ye model.The differences of photosynthetic parameters between inner and margin forests were examined.Stomatal conductance（gs）light-response curve were fitted using the mechanism model of gscoupled with a modified model of light-response of photosynthesis.The light-response characteristics of gswere investigated.Net photosynthetic rates（Pn）of Q.variabilis in the inner forest was higher than that in the margin.The initial light efficiency（α）was 12.4% more in the inner forest than that in the margin in July and August when photosynthetically active radiation was less than 200μmol·m^（-2）·s^（-1）.The ability to capture and utilize weak light of Q.variabilis leaves in the inner forest was obviously higher than that in the margin.When photosynthetically active radiation was higher than 200μmol·m^（-2）·s^（-1）,Pnof Q.variabilis leaves in the margin forest was larger than that in the inner.Under weak light conditions（0-200μmol·m^（-2）·s^（-1））,Pnof R.pseudoacacia in the inner forest was higher than that in the margin.Pnof R.pseudoacacia in the inner forest was less than that in the margin when light intensity was higher than 200μmol·m^（-2）·s^（-1）.The dark respiration rate（Rd）and light compensation point（Ic）in the inner forest were 50.0% and 42.8% lower than those in the margin.The less Rdand Icof the inner forest could reduce carbon loss and adapt to low photosynthetic rate.The stomatal conductance light-response of R.pseudoacacia in the inner forest significantly differed from that in the margin.The leaves of Q.variabilis and R.pseudoacacia had strong adaptability to the changes of light condition.The values of maximum net ph

关 键 词：栓皮栎 刺槐 气体交换参数 光环境 光合参数 

分 类 号：S792.18[农业科学—林木遗传育种] S792.27[农业科学—林学]