全球气候变暖对中国种植制度可能影响Ⅳ.未来气候变暖对东北三省春玉米种植北界的可能影响

【目的】在全球气候变化背景下,中国气温明显升高已成为共识,这一变化对中国农业生产尤其是对种植制度及作物布局的影响越来越受到农业生产管理部门和专家学者的重视。【方法】本文结合SRES的两种排放情景A2(强调经济发展)和B1(强调可持续发展)预估的未来气候数据,采用经验频率法计算不同保证率下的积温,探讨了未来气候情景下东北三省春玉米不同熟型品种种植北界的变化趋势,同时探讨了未来气候情景下研究区域内春玉米缺水率的变化趋势。【结果】未来气候情景下,在不考虑CO2浓度升高对作物生长发育影响的前提下,东北三省春玉米不同熟型品种种植北界不同程度向北移动,在界限敏感区域内中晚熟品种替代早熟品种,使得玉米生育期延长,干物质积累增加,可以提高东北三省春玉米产量。然而在未来21世纪中期,春玉米缺水率亦呈现增加的趋势,为种植界限北移带来一定的风险。【结论】在未来气候条件下,春玉米不同熟型品种种植北界北移需综合考虑热量和水分的影响,适区种植以减少由于干旱造成的春玉米减产。

The Possible Effects of Global Warming on Cropping Systems in China Ⅳ.The Possible Impact of Future Climatic Warming on the Northern Limits of Spring Maize in Three Provinces of Northeast China

【Objective】 The fact that temperature in China had increased significantly in the context of global climate change has become a consensus. The effects of this change on China’s agricultural production, especially on cropping systems and crop distribution have attracted more and more attention of the Chinese government and scientists. 【Method】 In this paper, using the accumulated temperature with different guarantee rates by empirical frequencies method, the changes of the northern limits of different maturity-types of spring maize varieties and the changes of water deficient ratio in the study region were analysed, based on the meteorology data in both A2 and B1 climatic scenarios. 【Result】 The northern limits of different maturity-types of spring maize varieties moved northward with different degrees without considering the effect of elevated CO2 concentration on the growth and development of crop in future climate scenarios. In the sensitive region, the early-maturity varieties will be replaced by the middle and late maturity varieties, making the growth period longer and the dry matter increased, which can improve the yield of spring maize in three provinces of Northeast China. However, the increase of water deficient ratio will bring a certain risk of northward movement in the 21 mid-century. 【Conclusion】 Heat and water resources should be comprehensively considered in the northward movement of different maturity-types of spring maize varieties. Spring maize should plant in the suitable region in order to reduce the loss of maize yield due to the draught.