碳四植物光合生化机理模型的叶片含水量修正  

Modification of Leaf Water Content for the Photosynthetic and Biochemical Mechanism Model of C4 Plant

作　　者：冯晓钰 周广胜[2] Feng Xiaoyu;Zhou Guangsheng(Jinhua Meteorological Service of Zhejiang,Jinhua 321000;Chinese Academy of Meteorological Sciences,Beijing 100081)

机构地区：[1]浙江省金华市气象局,金华321000 [2]中国气象科学研究院,北京100081

出　　处：《应用气象学报》2022年第3期375-384,共10页Journal of Applied Meteorological Science

基　　金：国家自然科学基金重点项目(42135014);金华公共气象服务创新团队项目。

摘　　要：叶片光合作用的准确模拟对陆地生态系统模型及全球变化对植被影响研究具有重要意义。水分是影响光合作用的重要因素,目前研究多采用土壤含水量表示,而非直接起作用的叶片含水量,这限制了光合作用的准确模拟。以玉米为研究对象,利用2014年6—10月中国气象科学研究院固城生态与农业气象试验站玉米6个水分梯度持续干旱试验数据,结合光合生化机理模型,定量研究最大羧化速率与叶片含水量的关系。结果表明:两者呈显著二次曲线关系,其拟合方程的决定系数达0.88;参数不同时,最大羧化速率的绝对值不同,但归一化后的叶片含水量修正函数与参数无关,当叶片含水量为80%左右时,其修正函数值为1,当叶片含水量降至70%左右时,其修正函数值为0。研究从叶片含水量影响方面完善了碳四植物光合生化机理模型,可为进一步提高光合作用模拟的准确性和玉米干旱监测预警提供参考。The accurate simulation of leaf photosynthesis is of great significance to the study of terrestrial ecosystem model and understanding the impact of global change on vegetation.To improve the description of photosynthesis from phenomenon to mechanism,empirical model is gradually replaced by photosynthetic biochemical mechanism model,in which the photosynthetic biochemical mechanism model proposed by Farquhar is widely recognized and used.The effect of CO_(2) concentration on plant photosynthesis is considered by the model,but the response of plant photosynthetic parameters to temperature and light intensity is studied without considering water stress.Water is one of the important raw materials of photosynthesis,which directly affects leaf stomatal conductance,transpiration rate and photosynthetic rate,and then affects plant photosynthesis.Therefore,many experiments are carried out and the water response function is gradually established.However,these studies mostly focus on soil water content rather than leaf water content that directly affects photosynthesis,limiting the accurate simulation of photosynthesis.Taking maize from North China as the research object,drought simulation data are studied based on six water gradient tests which are carried out at Gucheng Ecological and Agro-meteorological Experimental Station of Chinese Academy of Meteorological Sciences from June to October in 2014.Different from the previous empirical model of photosynthesis,a C4 plant photosynthetic biochemical mechanism model developed from the biochemical mechanism model proposed by Farquhar and modified by von Caemmerer is applied.The sampling blades and the environmental factors such as temperature,CO_(2),relative humidity,and light intensity are kept consistent,and the temperature difference between different observation times are adjusted to quantitatively study the relationship between leaf water content and maximum carboxylation rate accurately.The results show that the relationship between them can be expressed in a quadratic c

关 键 词：叶片含水量 光合作用 定量模拟 玉米 

分 类 号：Q945.11[生物学—植物学]