山东省设施农业生产季连阴天时空演变特征及其影响

利用山东省59个国家级气象观测站1961—2018年逐日日照时数及32个设施农业小气候观测站2008—2018年逐日气温观测资料，采用线性回归法、Mann-Kendall突变检验法及反距离权重插值法等分析了设施农业生产季连阴天时空分布和变化规律及其对设施内气温条件的影响。结果表明，时间上，过去58 a山东省连阴天年总发生次数和总连阴天数分别以1.7次·a-1和6.5 d·a-1的趋势增加，且年总发生次数在1999年发生突变；空间上，过去58 a连阴天总发生次数和总连阴天数均呈“东北—西南”向增多分布，聊城和德州地区的增加较其他区域更为明显，单站年发生次数和连阴天数增加超过0.06次·a-1和0.2 d·a-1，且变化趋势在聊城等15个和13个站点通过显著性水平为0.05的显著性检验；随着连阴天数增加，设施内气温降温幅度会增大；相同连阴天数时，平均气温和最低气温降幅春秋季大于冬季，分析其原因可能是春秋季基础温度高于冬季，从而更容易引起温度的剧烈变化所导致。研究结果可为有关部门研究设施农业种植布局和指导设施农业生产及防灾减灾提供理论支持。

Spatio-temporal characteristics and influence of continuous overcast skies in the production season of facility agriculture in Shandong Province

Based on the observed daily sunshine hours of 59 national meteorological stations from 1961 to 2018 and daily temperature data of 32 microclimate meteorological stations for facility agriculture from 2008 to 2018 in Shandong Province, this study analyzes the spatial and temporal distribution and trend of continuous overcast skies and their influence on the temperature condition for facility agriculture in the production season using linear regression, Mann-Kendall test, and inverse distance weighted (IDW) interpolation methods. The results are as follows. 1) Temporally, the total times and days of continuous overcast skies increase by 1.7 times·a-1 and 6.5 d·a-1 in the past 58 years, respectively, and the mutation of the total times occurs in 1999. 2) Spatially, the total times and days of overcast skies increase from the northeast to the southwest of Shandong Province. The increase is much more obvious in Liaocheng and Dezhou with the total times and days at a single station increasing by more than 0.06 times·a-1 and 0.2 d·a-1. Moreover, the trend passes the significance test at 0.05 level in the 15 and 13 stations such as Liaocheng. 3) The temperature dropping rate in facility agriculture increases as the days of continuous overcast skies increase. 4) For the same days of continuous overcast skies, the dropping rate of the average and the minimum temperature in spring and autumn is greater than that in winter, and the reason may be that the temperature in spring and autumn is basically higher than that in winter, which is more likely to cause dramatic changes in temperature. The results can provide theoretical support for relevant departments to study the planting layout and to guide production and disaster prevention and mitigation for facility agriculture.