Abstract:

To study the impact of spring climate change on winter wheat yield in the representative area of Longdong loess plateau, the Xifeng district of Qingyang city, utilizing the data on the average temperature, precipitation, sunshine hours in spring and winter wheat yield from 1985 to 2020, the characteristics of spring climate change and its impact on winter wheat yield formation were analyzed. The results showed that the spring average temperature anomaly increased significantly with the years, with a rising rate of 1.04℃ per decade, which was much higher than the global and national average levels. The precipitation anomaly percentage showed a fluctuating decreasing trend, with a decreasing rate of 2.72 mm per decade. The sunshine hours anomaly percentage showed an increasing trend, with an increasing rate of 2.45 h per decade. The winter wheat yield showed an increasing trend, with an increasing rate of 470.14 kg/hm² per decade. The match between the climate resources in the critical growth period of winter wheat and its yield formation was reflected by the abundance or scarcity of the climate yield. Over the 36 years, the abundance of production years with good matching accounted for 58%, and the scarcity of production years accounted for 42%. The years with meteorological conditions favorable for winter wheat yield formation accounted for 53%, and unfavorable years accounted for 47%. The research results can guide crop layout and agricultural production in the region according to climate change, seek advantages and avoid disadvantages, and play positive role in promoting the quality and production of winter wheat.

Key words: spring climate, change characteristics, winter wheat climate yield, impact analysis and evaluation