基于DEM的近60年辽宁省玉米生长季气温变化特征分析

DEM-based Analysis of Temperature Change Patterns During Maize Growing Season in Liaoning Province Over Recent 60 Years

为研究辽宁省近60年玉米生长季热量变化及空间分布,利用1961—2020年辽宁省52个气象观测站逐日平均气温及数字高程模型(DEM),采用空间混合差值法,计算辽宁省近60年玉米各发育期平均气温年际变化及空间分辨率为100 m的精细化空间分布情况。结果表明,辽宁省春玉米全生育期内逐年气温上升趋势明显,气候倾向率为0.20℃/10年。播种到3叶期、7叶—拔节期、抽穗—乳熟期和成熟—收获期内的平均气温均呈显著上升趋势,气候倾向率分别为0.23、0.18、0.19、0.22℃/10年。平均气温在玉米生长前期上升趋势显著,有利于玉米苗期抵御低温冷害风险。空间分布上,气温的高值区位于辽宁中部和环渤海一带,低值区位于朝阳建平北部和辽宁东部山区。玉米各生育期内平均气温总体呈西部高于东部、沿海高于内陆等特点。

The present study aimed to investigate the heat change and spatial distribution during maize growing season in Liaoning Province over recent 60 years.Using the digital elevation model(DEM),we analyzed the daily average temperature between 1961 and 2020 recorded by 52 meteorological stations in this province;based on this analysis,we calculated the inter-annual change of average temperature and the spatial distribution with spatial resolution of 100 m of Liaoning Province in recent 60 years by using the spatial mixed difference method.The results showed that the temperature in the whole growth period of maize in Liaoning Province increased significantly,with the climate trend rate of 0.20℃/10 years.The temperature in Liaoning Province rose significantly in recent years,bringing warm conditions favoring maize growth.The average temperature rose significantly through the periods between sowing and three-leaf stages,between seven-leaf and jointing stages,between tasseling and filling stages,and between mature and harvest stages,which had the climate trend rates of 0.23℃/10 years,0.18℃/10 years,0.19℃/10 years,and 0.22℃/10 years,respectively.The average temperature rose significantly in the early growth stage of maize,which reduced the risk of chilling injury in maize seedling stage.In terms of heat spatial distribution,the high temperature areas are in central Liaoning Province and around the Bohai Sea,while low temperature areas are northern Jianping County and eastern Liaoning Province.The average temperature in all growth stages was higher in the west than in the east of Liaoning,and higher in its coastal areas than in its inland areas.