气候变化对中国粮食生产、消费及经济增长的影响研究——基于中国农业一般均衡模型

Climate Change Affecting Grain Production, Consumption and Economic Growth in China:Based on the Agricultural CGE Model

为研究气候变化对粮食生产、消费及经济增长影响,将气候变化影响粮食产量的研究结果作为一般均衡模型的政策模拟方案,通过构建的基期模拟预测研究了到2050年中国粮食生产、消费及其经济增长两个方面的内容。模拟结果显示:(1)到2050年,中国粮食生产总量在A2情景(高排放)下为629185×103t,在B2(中低排放)情景下为601859×103t。总需求在B2情景下为626609×103t,在B2情景下为561093×103t,不考虑损耗及库存,粮食供需基本平衡,供给略大于需求。(2)考虑CO_2的肥效作用,到2050年,气候变化对中国宏观经济和部门经济产生有利影响,实际工资、实际GDP、投资、家庭消费、出口等宏观指标相比于基期都有所上升,对主要农业部门及工业和服务业部门的产出、消费、进出口也是有利影响。而不考虑CO_2的肥效作用则会得到相反的结论。(3)在A2情景下气候变化对中国宏观经济和部门经济的有利影响要大于B2情景下的影响。(4)从气候变化对产出和需求影响的变化结果来看,从总体上来说,考虑CO_2的肥效作用,无论是A2还是B2情景下,都导致供给增加,进口减少,增加的供给量大于需求。因此,考虑CO_2肥效的作用,会增强供给的保障,有利于维护中国的粮食安全。而不考虑CO_2的肥效作用,无论是A2还是B2情景下,都导致供给减少,进口增加,减少的供给量大于需求的变化量,不利于维护中国的粮食安全。

To study the effect of climate change on grain production, consumption and economic growth, usinggrain production and climate changes in previous researches, policy schemes in base period were simulated,grain production, consumption and economic growth by 2050 in China were predicted based on the computablegeneral equilibrium（CGE） model. The results showed that（1） by 2050, under the high carbon emissionscenario（A2）, the total grain yield was 629185 thousand tons, and the total consumption demand was 626609 thousand tons; under the medium and low carbon emission scenario（B2）, the total grain yield was 601859 thousand tons, and the total consumption demand was 561093 thousand tons. Without regard to the loss andinventory, the supply and demand of grain was basically in a balance with supply slightly bigger than demand.（2） When taking the fertilizer effect of CO2 into consideration, climate change would have positive effects onChina＇s macro and sector economy by 2050. Macroeconomic indicators such as real wages, real GDP,investment and household consumption and export all increased compared with that of the base period; fromthe aspect of sector economy, climate change also had positive effects on the output, consumption, import andexport of the primary, secondary and tertiary industry. However, the results were opposite without consideringthe fertilizer effect of CO_2.（3） The positive effect of climate change on China＇s macro and sector economyunder A2 scenario was higher than that under B2 scenario.（4） Considering the effect of climate change ongrain yield and demand, when taking the fertilizer effect of CO_2 into consideration, grain supply increased andimport reduced under both A2 and B2 scenarios, and the increased supply quantity was larger than that of thedemand. Therefore, taking the fertilizer effect of CO_2 into consideration would guarantee the supply and wasbeneficial to food security in China, while without considering the fertilizer effect of CO_2, the results wereopposite.