资助项目:国家自然科学基金 “黑河中游灌区尺度土地利用变化及其驱动力研究”(41561024)
第一作者:焦文慧(1995—),女,山东济南人,硕士,主要从事农业气象方面的研究。E-mail:jiaowenhuixlt@163.com 通信作者:张勃(1963—),男,甘肃庆阳人,博士生导师,教授,主要从事区域环境与资源开发等方面的研究。E-mail:zhangbo@nwnu.edu.cn
春玉米生长发育及其产量受干旱影响很大,明晰不同生育期干旱特征对为保障春玉米安全和防旱减灾具有重要意义。基于松嫩平原及周边42个站点1960—2016年逐日气象资料和春玉米生育期资料,分别计算各生育期逐日相对湿润度,将其作为春玉米生育期干旱等级评价指标,并应用线性倾向估计法、Mann-Kendall法和相关分析法,分析了近57年松嫩平原春玉米全育期及各主要生育期干旱变化特征。结果 表明:(1)松嫩平原春玉米全育期、并进期和生殖生长期呈干旱化趋势,营养生长期呈湿润化趋势。(2)干旱频率、强度和持续时间在全育期、并进期和生殖生长期呈增加趋势,在营养生长期呈下降趋势。并进期干旱在1990s最严重,其他生育期和全育期均在2000s最严重。各生育期干旱程度表现为营养生长期>生殖生长期>并进期。(3)全育期及各生育期多年平均干旱频率、强度和持续时间呈东北向西南递增的变化趋势,从东北向西南干旱加强。(4)松嫩平原春玉米生育期干旱变化特征对降水量、日照时数和相对湿度的变化最敏感。研究结果可为松嫩平原春玉米干旱预报及生产规划等提供参考。
Drought has great influence on the growth, development and yield of spring maize. It is of great significance to clarify the drought characteristics at different growth stages to ensure the safety of spring maize, drought prevention and disaster reduction. Based on the daily meteorological data and data in the growth period spring maize from 42 meteorological stations of Songnen Plain from 1960 to 2016, the daily relative moist index(M)of different growth periods was calculated, and the relative moist index as was taken as a drought index in spring maize growth period, the methods of linear regression, Mann-Kendal test, and correlation analysis were used to analyze the drought variation characteristics of spring maize in Songnen Plain in recent 58 years. The results showed that:(1)the trend of drought showed in the complete growth period, vegetative and reproductive transition period and the reproductive growth period of spring maize in Songnen Plain, and the trend of wetting showed in the vegetative growth period;(2)the drought frequency, intensity and duration had the increasing trend in complete growth period, vegetative and reproductive transition stage and the reproductive growth period, and had the decreasing trend in the vegetative growth period; In the vegetative and reproductive stage, the most serious drought occurred in the 1990s, and the most serious drought in the other growth and complete stages occurred after 2000; the drought degree of each growth period decreased in the order: vegetative growth period>reproductive growth period>vegetative and reproductive stage;(3)the average drought frequency, intensity and duration in all growth period increased from northeast to southwest, and the drought increased from northeast to southwest;(4)the drought variation of spring maize in Songnen Plain was most sensitive to the changes of precipitation, sunshine hours and relative humidity. These results can provide reference for drought forecast, planning of spring maize production in Songnen Plain.