免耕旱地小麦产量的光温效应

Effects of the light and temperature on dry land wheat yield under different tillage systems

为探索光温对小麦(Triticum aestivum)产量影响的机制和规律,设计光照和温度2因素7水平的模拟试验,运用模型模拟1971-2005年35a间光照和温度变化下小麦的产量,并采用回归方法分析免耕覆盖(NTS)、传统耕作(T)和免耕(NT)3种耕作措施下,年平均光照和温度变化对小麦产量的影响。结果表明,不同耕作措施下,小麦产量随年平均光照和温度的升高呈二次抛物线型下降变化,且NTS的减产效应大于T和NT。当光照不变、年均温升高时,3种耕作措施下小麦均表现为减产,且年平均温度每升高1℃,最大减产率可达16.2%,平均减产率7.6%。当温度不变、年平均光照增加时,3种耕作方式下小麦产量均降低,且年平均光照每增加1MJ·m-2,小麦最大减产率可达13.8%,平均减产率3.9%。3种耕作方式中,NTS的产量改变率均大于T和NT,表明光照或者温度升高相同的值时,NTS耕作措施下的小麦产量减产效应大于其他两种耕作方式。相反,如果降低相同的温度或者光照,NTS的增产效应明显大于其他两种耕作方式。

Experiments with two factors and seven levels were designed to explore the influences of light and temperature variations on wheat yields the test of light and temperature. And then, amodelwas employed to simulate wheat yields under different light and temperature from 19＇71 to 2005 year and analyze the effects of light and temperature on wheat yield under 3 tillage systems.T＇he results showed the relationships between wheat yield and the light and temperature were quadrati： parabola with decreased type. Meanwhile, the reduction effect of wheat yield of NTS was greater than that of T and NT. If the annual average temperature rise 1 ℃ with constant light,wheat yield decreased ur der these 3 cultivation and maximum yield reduction rate was 16.2% with average of 7.6%. If the average light increase 1 MJ· m-2 with constant temperature, wheat yield decreased under these 3 cultivation ard maximum yield reduction rate was 13.8% with average of 3.9%. NTS yield change was greater than that of T and NT which suggest that the decreasing effect of NTS on yield was greater than the other two tillage system with the rise oflight or temperature.