山西省1981—2018年农业霜冻危险性时空变化特征

Temporal and Spatial Variation Characteristics of Agricultural Frost Risk in Shanxi Province from 1981 to 2018

根据1981—2018年山西省108个气象站逐日最低气温资料,采用Mann-Kendall突变检验法、霜冻频率等级及强度指数、致灾因子危险性指数、霜冻站次比等方法和指标对山西省低温霜冻发生频率及危险指数进行时空变化分析。结果表明:1981—2018年山西省农业霜冻发生频率差异较大,农业霜冻发生频率波动降低,低频率农业霜冻占主导。山西省农业霜冻站次比呈波动下降趋势(下降速率为-8.8%/10a),农业霜冻发生范围逐步减少。根据Mann-Kendall分析,霜冻总次数减少从1998年开始。农业霜冻危险性具有明显的空间异质性,南部危险指数为0,中部地区为0~0.2,北部地区为0.4~0.9,呈现由南向北增加的趋势,高危险区域主要集中在吕梁山北部。

In order to explore the temporal and spatial variation characteristics of frost and its risk in Shanxi Province under the background of climate warming and frequent extreme weather events,based on the daily minimum temperature data of 108 meteorological stations in Shanxi Province from 1981 to 2018,the Mann-kendall mutation test method and the frost frequency level(P_(i)),intensity index(AT),hazard factor risk index(FI)and frost station times ratio(P_(j))and other indicators were used to analyze the temporal and spatial changes of the frequency and risk index of low temperature frost in Shanxi Province.The results show that:In the past 38 years,the frequency of agricultural frost in Shanxi Province varies greatly.The frequency of agricultural frost fluctuates and decreases,and the trend is dominated by low frequency agricultural frost.The ratio of agricultural frost stations in Shanxi Province showed a fluctuating downward trend(the decline rate was-8.8%/10a),and the occurrence range of agricultural frosts gradually decreased.According to the Mann-kendall analysis,the abrupt reduction in the total number of frosts started in 1998.The risk of agricultural frost has obvious spatial heterogeneity.The southern hazard index is 0,the central region is 0~0.2,and the northern region is 0.4~0.9,showing a trend of increasing from south to north.The high-risk area is mainly concentrated in the northern part of Lvyliang Mountain.In some areas,the degree of agricultural frost risk has been significantly reduced.Frost disasters in Shanxi Province changed from latitude-dominated to altitude-dominated.The research results are of great significance for guiding regional agricultural production,adjusting the structure of crops,and promoting stable and high yields of agricultural products.