江苏省冬油菜生育期内低温事件的年际变化及对产量的影响

为探讨气候变化对我国油菜生产带来的可能影响，选取江苏省地区52个气象站1961—2012年日气温资料及冬油菜产量逐年数据，采用M-K趋势检验探求冬春季节8种低温指数的变化趋势，并依托一阶差分法探讨低温指数与产量的数量关系。结果表明：（1）1961-2012年间省内大部分地区冬春季节低温事件的总天数、连续低温事件的场次、强度及持续性呈现出显著的减弱趋势；（2）不同类型低温指数中，FI1（越冬期日最低气温<-5℃的总天数）与CI4（蕾薹期连续日最低气温<0℃天气的最长持续时间）对冬油菜产量的负效应最为显著；（3）各站点产量对FI1及CI4敏感性分析表明江苏省北部地区冬油菜种植对低温灾害事件更为敏感；（4）1961-2012年间江苏大部分地区FI1及CI4的减少趋势给研究区冬油菜产量带来了一定幅度的增产。

Inter-annual Variation of Low Temperature Events in the Growing Period of Winter Oilseed Rape in Jiangsu and Its Effect on Yield

The purpose of this study is to explore the possible impacts of climate changes on oilseed rape production. Based on the daily temperature record and yield data for winter oilseed rape rice at 52 meteorological stations in Jiangsu during 1961-2012, the changing trends of eight types of low temperature indices in winter and spring were calculated using M-K test, and the quantitative relationship between low temperature indices and yield were discussed by first order difference method. The results was as fellow: (1) During 1961-2012, the total days of low temperature events, and the number, intensity, persistence of continuous low temperature events in most areas of the province showed strong decreasing trends; (2) among the different precipitation indices, FI1(total days with minimum temperature <-5℃ during wintering stage) and CI4 (the longest duration of continuous days with minimum temperature <0℃ during budding stage) had the most significant negative effect on winter oilseed rape yield; (3) sensitivity analysis for yield to FI1 and CI4 showed that oilseed rape planting in the northern areas was more sensitive to low temperature events; (4) the decreasing trend of FI1 and CI4 in most areas of Jiangsu brought a certain increase for winter oilseed rape yield during 1961-2012.