Abstract:
The rapid growth of China\'s demand for grains is expected to continue in the coming decades, largely as a result of the increasing feed demand to produce protein-rich food. This leads to a great concern on future supply potentials of Chinese agriculture under climate change and the extent of China\'s dependence on world food markets. While the existing literature in both agronomy and climate economics indicates a dominance of the adverse impacts of climate change on rice, wheat, and maize yields, there is a lack of study to assess changes in multi-cropping opportunities induced by climate change. Multi-cropping benefits crop production by harvesting more than once per year from a given plot. To address this important gap, we established a procedure within the agro-ecological zones (AEZ) modeling framework to assess future spatial shifts of multi-cropping conditions. The assessment was based on an ensemble of five general circulation models under four representative concentration pathway scenarios in the phase five of coupled model inter-comparison project and accounted for the water scarcity constraints. The results show significant northward extensions of single-, double-, and triple-cropping zones in the future which would provide good opportunities for crop-rotation-based adaptation. The increasing multi-cropping opportunities would be able to boost the annual grain production potential by an average scale of 89(±49) Mt at the current irrigation efficiency and 143(±46) Mt at the modernized irrigation efficiency with improvement between the baseline (1981-2010) and the mid-21st century (2041-2070).
摘要:
中国对谷物需求的快速增长预计将在未来几十年继续,主要是由于生产富含蛋白质食物的饲料需求增加。这引起了人们对气候变化下中国农业未来供应潜力和中国对世界粮食市场依赖程度的高度关注。虽然农学和气候经济学的现有文献表明,气候变化对水稻的不利影响占主导地位,小麦,和玉米产量,缺乏评估气候变化引起的多作机会变化的研究。通过每年从给定地块收获一次以上,多作有利于作物生产。为了解决这一重要差距,我们在农业生态区(AEZ)建模框架内建立了一个程序,以评估多作条件的未来空间变化。该评估基于耦合模型相互比较项目第五阶段中四个代表性浓度途径方案下的五个一般循环模型的集合,并考虑了缺水约束。结果表明,单,double-,和未来的三作区,这将为基于作物轮作的适应提供良好的机会。越来越多的种植机会将能够在当前的灌溉效率下将年谷物生产潜力平均提高89(±49)Mt,在现代化的灌溉效率下提高143(±46)Mt,并在基线之间提高(1981-2010)和21世纪中叶(2041-2070)。