长江下游平原小麦生长季气候变化特点及小麦发展方向

利用长江下游平原 10个样点 196 0～ 1997年的逐日气象资料 ,分析了近 40年来小麦生长季的气候变化特点 ;根据GISSTransientB模型的有关网格点值 ,展望了研究区域未来 5 0年气候演变的趋势 ;采用上述各样点近40年的小麦单产资料和同期气候资料 ,评价了当前小麦气候产量的变化规律 ;将经修正的CERES Wheat模型在各样点未来不同年份的气候变化情景下运行 ,并考虑大气CO2 增长对小麦产量的增益作用 ,模拟了今后 5 0年研究区域小麦气候产量的走势。结果表明 :近 40年来 ,长江下游平原小麦生长季已出现了明显的增温现象 ,并伴随日照时数和降雨日数的显著降低 ,小麦气候产量因暖冬、阴湿寡照和后期高温等呈下走趋势 ) ;今后 5 0年 ,这种下走趋势将因大气CO2 浓度增长而一定程度地得到缓解或补偿。因此 ,在研究区域目前种植结构调整中 ,合理压缩小麦面积是顺应气候变化的举措之一 ,但不能因此“封杀”小麦在研究区域的应有地位。培育耐阴的弱冬性或春性的优质小麦品种和发展多元化种植 ,将是研究区域今后利用冬季气候资源的发展方向。

Characteristics of Climate Change during Wheat Growing Season and the Orientation to Develop Wheat in the Lower Valley of the Yangtze River

Characteristics of climate change during wheat growing season in the past 38 years in the Lower Valley of the Yangzte River were analyzed using the local daily climatic data at 10 sites from 1960 to 1997.Trend of climate change in the next 50 years was prospected,based on outputs of the GISS transient B model.Wheat climatic yield in the past 38 years was estimated,using a statistical method and that in the next 50 years was simulated by running the modified CERES Wheat model under the climate change scenarios in 2010,2030 and 2050,generated by the GISS transient B model.The direct effects of CO 2 on wheat yield were also considered.The results indicate that the temperature during wheat growing season in the past 38 years has sustainablly and significantly increased,in company with reduction of both the sunshine duration in hours and rainy days and this trend would continue in future 50 years. Warming winter,lack of sunshine,humid weather,and high temperature in the later stage of wheat growth would result in decrease in wheat yield.But the direct effects of CO 2 would mitigate even compensate for the negative effects of climate warming in the studied region.It is,therefore,one of the strategies for adapting to climate change to reduce reasonably the wheat area,but undesirable to entirely refute the wheat proper role in regulating farming patterns.It will be the orientation to breed wheat varieties with a good quality and high temperature and wet resistance and,to diversify the farming patterns for efficiently using the winter climatic resources in future.