东北地区大豆冷害指标构建及变化特征

Construction of Soybean Chilling Damage Indicator and Its Evolution Characteristics in Northeast China

  • 摘要: 冷害是东北地区大豆减产的主要原因之一,冷害指标是冷害监测预警的重要依据。以东北地区大豆为研究对象,基于1971—2020年气象站点逐日平均气温数据、1992—2020年农业气象站大豆发育期数据和历史灾情数据,以热量指数为冷害指标,构建大豆灾害样本序列,利用Kolmogorov-Smirnov(K-S)分布拟合检验获得冷害指标的概率分布,通过t分布区间估计方法确定指标等级阈值,并进行验证。在此基础上,讨论冷害时空变化特征。结果表明:冷害等级与冷害指标完全匹配率达84.4%,该指标等级阈值可以较好反映东北地区大豆冷害发生情况;在相同冷害等级下,大豆三真叶-开花-结荚阶段冷害等级阈值较高,播种-出苗-三真叶阶段相对较低;20世纪70年代的冷害频次最高,1993年前后发生突变,之后呈下降趋势;黑龙江省最北部及吉林省东南部为冷害高发地区,以此为中心冷害频次向四周递减;随年代际变化,冷害频次高值区逐渐缩小,低值区逐渐北伸扩大。

     

    Abstract: Chilling damage is the major cause of soybean yield reduction in Northeast China. Chilling damage indicator is an important basis for the monitoring and early warning. Taking soybean in Northeast China as the research object, based on daily average temperature data of 98 meteorological stations from 1971 to 2020, the soybean growth period data and historical disaster data of 42 agro-meteorological stations from 1992 to 2020, using heat index as the indicator, the disaster sample sequences of soybean under 5 growth stages and 3 chilling damage levels are constructed by disaster data. Probability distribution fitting and Kolmogorov-Smirnov test methods are used to obtain the probability distribution of chilling damage indicator, and then the t-distribution interval estimation method is used to determine the damage level threshold, and finally the indicator is verified. In addition, the temporal and spatial characteristics of chilling disaster are studied by applying trend analysis, Mann-Kendallt test method and other methods. The results show that the perfect match rate of disaster level and chilling damage indicator is 84.4%. Therefore, this level threshold of the indicator can well reflect the occurrence of soybean chilling damage in Northeast China. Under the same chilling damage level, the threshold value of chilling damage level in the three-leaf-flowering-podding stage is higher, and that in the sowing-emergence-three-leaf stage is relatively lower. Soybean has higher heat demand in the middle and late stage of growth and development, and lower heat demand in the early stage of growth and development. The frequency of chilling damage is the highest in the 1970s, and the mutation occurred around 1993 and then showed a downward trend until 2004. The spatial distribution of chilling injury frequency in each development stage shows the same change characteristics, and the highest value area is the widest in podding-mature stage. The areas with high incidence of cold damage is the Greater Khingan Range in the northernmost of Heilongjiang Province and the Changbai Mountain in the southeast of Jilin Province. And the frequency of chilling damage shows a decreasing trend around this center. With the inter-decadal change, the high-value area gradually shrinks and the low-value area gradually expands northward.

     

/

返回文章
返回