论文部分内容阅读
明确黄土高原地区降水和气温变化对冬小麦田土壤水分和产量的影响,对探索适应气候变化的冬小麦田间管理措施具有重要的现实意义。论文在验证EPIC模型对冬小麦田土壤水分模拟精度的基础上,以历史气象数据为基础,设置TR1、TR2和TR3三个气候情景,采用作物模型模拟的方法,研究黄土高原冬小麦田土壤水分和冬小麦产量对降水和气温变化的响应。结果显示:1)1961—2010年黄土高原降水呈降低趋势,其年际间变化幅度和频率均有所增加。与1961—1970年相比,洛川、长武、运城和延安的年均降水量在2001—2010年间分别降低了18.1%、13.6%、18.8%和24.9%,其变差系数分别增加了0.029、0.087、0.02和0.057。1961—2010年黄土高原气温呈波动性增加趋势,其中日最低气温增加幅度大于日最高气温增加幅度。与1961—1970年相比,日最高气温在2001—2010年间增加了0.30~0.84℃,而日最低气温增加了1.00~1.55℃。2)EPIC模型能够较好地模拟黄土高原冬小麦田土壤水分动态变化规律,0~2.0 m土层土壤湿度观测值与模拟值间的相对均方根误差RRMSE值为6.0%~14.0%,R2和模型效率ME值分别为0.824和0.815。3)黄土高原地区降水的减少和最高气温的增加均不利于冬小麦生产,而最低气温的提高对冬小麦生产较为有利。洛川、长武、运城和延安冬小麦产量因年降水量的降低而分别减产了8.5%、7.6%、11.7%和12.3%;因日最高气温的升高分别减产了6.4%、6.8%、7.2%和-3.0%;因日最低气温的提高而分别增加了8.8%、10.2%、1.5%和12.0%。因此,为适应降水减少和日最低气温升高的趋势,黄土高原冬小麦生产区应适当调整冬小麦播期,研究并推广保水节水技术措施,充分利用气候变化对冬小麦生产的有利因素,克服不利因素,确保冬小麦的可持续生产。
A clear understanding of the effects of changes in precipitation and temperature on the soil moisture and yield of winter wheat fields in the Loess Plateau is of great practical significance in exploring winter wheat field management practices adapted to climate change. Based on the historical meteorological data, three climatic scenarios of TR1, TR2 and TR3 were set up on the basis of verifying the precision of soil moisture simulation in winter wheat field by EPIC model. The crop model simulation was used to study the effects of soil moisture and winter wheat Response of Yield to Precipitation and Temperature Changes. The results show that: 1) Precipitation in the Loess Plateau decreased from 1961 to 2010, and its annual variation range and frequency both increased. Compared with 1961-1970, the average annual precipitation of Luochuan, Changwu, Yuncheng and Yan’an decreased by 18.1%, 13.6%, 18.8% and 24.9% respectively from 2001 to 2010, and their coefficient of variation increased by 0.029 , 0.087,0.02 and 0,057. From 1961 to 2010, the temperature in the Loess Plateau increased in a fluctuating manner. The daily minimum temperature increased more than the daily maximum temperature. Compared with 1961-1970, the daily maximum temperature increased from 0.30 to 0.84 ℃ in 2001-2010, while the daily minimum temperature increased by 1.00 to 1.55 ℃. 2) The EPIC model can better simulate the dynamic variation of soil moisture in winter wheat field on the Loess Plateau. The relative root mean square error (RMS) of soil moisture between 0 ~ 2.0 m soil layer is 6.0% ~ 14.0% The model efficiency ME values were 0.824 and 0.815, respectively. 3) The decrease of precipitation and the increase of the maximum temperature in the Loess Plateau are not conducive to the production of winter wheat, while the increase of minimum temperature is more favorable for the production of winter wheat. The output of winter wheat in Luochuan, Changwu, Yuncheng and Yan’an were reduced by 8.5%, 7.6%, 11.7% and 12.3% respectively due to the decrease of annual precipitation; the yield was reduced by 6.4%, 6.8% and 7.2% respectively due to the increase of the maximum daily temperature % And -3.0% respectively due to an increase of 8.8%, 10.2%, 1.5% and 12.0% respectively due to the increase of the daily minimum temperature. Therefore, in order to adapt to the trend of decreasing precipitation and daily minimum temperature, the winter wheat planting area in the Loess Plateau should adjust the sowing date of the winter wheat properly, research and popularize the technical measures of water conservation and water saving, make full use of the favorable factors of climate change on the production of winter wheat and overcome the unfavorable factors , To ensure the sustainable production of winter wheat.