基于APSIM模型旱地春小麦产量对温度和CO2浓度升高的响应

为了探索气候变化对旱地春小麦生长的影响机理,在田间试验的基础上通过调试APSIM模型参数,并对模型进行检验,用APSIM模型模拟7个温度水平和7个CO2浓度水平组合设计下的春小麦产量,并采用二次多项回归和通径分析研究春小麦产量对温度和CO2浓度升高的响应。结果表明:当温度不变,CO2浓度每升高100 mol·mol-1,春小麦平均增产4.9%,最大增产可达到14.6%;春小麦产量随CO2浓度升高呈递增型二次抛物线变化,但春小麦产量会出现报酬递减。当CO2浓度不变时,温度每升高1℃,春小麦平均减产6.1%,最大减产幅度高达14.2%;春小麦产量随温度升高呈递减型二次抛物线变化。温度和CO2浓度同时升高对春小麦产量存在正的协同作用,但温度对春小麦产量负效应大于CO2浓度对春小麦产量的正效应。温度和CO2浓度同时升高会对旱地春小麦产量形成不利。

Response of dryland spring wheat yield to elevated CO2 concentration and temperature by APSIM model

Global warming has become the most complicated issue facing agriculture production in the world and has received much attention in recent years.In order to determine the effect of global warming on spring wheat grain yield,field experimental results in the semiarid Dingxi region were used in APSIM model simulation and analysis.Spring wheat yield response to elevated CO 2 concentration and temperature was researched by simulating wheat yield under regular climatic conditions.The used APSIM model parameters were firstly modified and then verified based on field data.Spring wheat grain yield was stimulated by the APSIM model for a unitized design of 7 levels of temperature and CO 2 concentration.Regression equations and path analyses were also used to analyze the response of spring wheat grain yield to the changes in temperature and CO 2 concentration.The results showed that average increase in spring wheat grain yield was 4.9%,with a maximum increase of 14.6% when CO 2 concentration increased by 100 mol·mol-1 at constant temperature.A quadratic parabola relationship was noted between spring wheat grain yield and CO 2 concentration,which indicated an increasing tendency.Spring wheat grain yield increment reduced with further increases in CO 2 concentration.Average drop in spring wheat grain yield was 6.1%,with a maximum drop of 14.2% when temperature increased by 1 ℃ at constant CO 2 concentration.Also a quadratic parabola relationship was noted between spring wheat grain yield and temperature,which suggested a declining tendency.While synergy effects of temperature and CO 2 concentration on spring wheat grain yield were positive,although negative temperature effects on grain yield were more obvious than positive CO 2 concentration effects.The study concluded that global warming with increased temperature and CO 2 concentration negatively affected dryland spring wheat grain yield in semiarid China.