近20年江苏省气温和降水资源变化对稻麦生产的影响

利用数理统计及非线性回归模型等方法,探求江苏省近20 a气温和降水资源变化对稻麦生产的影响。结果表明:近20 a平均温度(Tavg)、最高温度(Tmax)和最低温度(Tmin)年增加趋势为0.050℃、0.056℃和0.061℃,降水量(Prec)变化不明显。在近年气候变暖下,冬小麦全生育期和营养生长期呈显著缩短趋势(p<0.05),分别年缩短0.41 d和0.70 d,而生殖生长期年显著延长0.32d(p<0.05)。冬小麦营养生长期和全生育期长短与该时段Tavg、Tmax和Tmin呈显著负相关(p<0.05)。水稻生育期长短变化不大,呈现整体向后推移趋势。2000s与1990s相比,冬小麦生育期缩短,而冬小麦和水稻播期均推迟,因此麦-稻换茬时间延长5 d,稻-麦换茬时间减少3 d。近20 a稻麦产量均呈增加趋势,稻麦周年产量每年极显著增加85.5 kg/hm²(p<0.01)。利用非线性模型分析表明,Tavg、Tmax和Tmin每增加1℃稻麦周年单产分别增产0.47%、0.10%和1.92%,主要是因为冬小麦产量增加幅度大于水稻减产幅度。为合理利用气候资源,可考虑推迟冬小麦播种,防止其冬前旺长。选育晚熟耐高温水稻品种,促进水稻生殖生长,提高产量。

IMPACTS OF TEMPERATURE AND PRECIPITATION RESOURCES CHANGE ON RICE-WHEAT PRODUCTION IN RECENT 20 YEARS IN JIANGSU PROVINCE

In this paper, we present the impacts of temperature and precipitation changing to wheat - rice production in Jiangsu province in recent 20 years, based on mathematical statistics and nonlinear regression model methods. Relative data shows that the maximum temperature(Tmax), minimum temperature(Tmin) and average temperature(Tavg) increased by 0.050,0.056 and 0.061℃ annually in recent 20 years. However, there is no obvious change in precipitation (Prec). As the climate warming, the whole growth process of winter wheat significantly reduced 0.41 d (day) (p<0.05) annually. Vegetative stage reduced 0.70 d every year. Reproductive stage extended 0.32 d significantly in each year (p<0.05). Both vegetative stage and whole growth stage of winter wheat and Tavg, Tmax, Tmin of each stage show negative correlation. Although the whole growth stage of rice pushed back integrally, the days didn't change. Comparing 2000s to 1990s, the growth stage of winter wheat was shortened, and both rice and winter wheat seeding time was delay. So replacement time of wheat-rice stubble extended 5d, while rice-wheat stubble reduced 3d. In recent 20 years, yields of wheat and rice are rising significantly (p<0.05). Annual yield significantly increased 85.5 kg·hm^-2 per year(p<0.01). By using nonlinear regression model analysis, the annual yield increased 0.47%, 0.10% and 1.92% respectively, if Tavg, Tmax and Tmin increased by 1℃, because the increasing yield of winter wheat is higher than the yield reduction of rice. In order to take advantage of the changing climate, postponing breeding to prevent vigorous growth of winter wheat before winter is suggested. Select late varieties with high-temperature tolerance to promote the reproductive growth would also help increasing the production of rice.