利用2012年12月至2013年1月和2013年12月至2014年1月两个生长季沈阳和喀左地区日光温室的小气候观测数据，基于日光温室番茄实际低温冻害发生及影响因素分析，构建日温差指数，确定辽宁地区日光温室番茄果实膨大期低温冻害的指标，并采用回归分析方法建立了日光温室温度预报模型。结果表明：日光温室内持续低温、寡照及高湿综合作用造成了番茄低温冻害的发生。在日光温室内高湿的环境条件下，日光温室外出现阴雨雪天气，且寡照天气持续3 d，日光温室内最高气温小于10℃，最低气温小于5℃，且5℃以下低温持续时间达15 h以上时，将出现低温冻害。利用日光温室内外逐时气温数据建立温室内逐时气温预报模型，18时至翌日08时逐时气温≤3℃误差的预报准确率达86％以上。因此，利用确定的日光温室内番茄低温冻害指标和建立的日光温室内逐时气温预报模型，可实现温室内番茄低温冻害预警，提高日光温室防灾减灾能力。%Based on greenhouse microclimate observation data in two growing seasons from December 2012 to Jan-uary 2013 and from December 2013 to January 2014,the occurrence of frost damage for tomatoes in greenhouse and their influencing factors were analyzed.The diurnal temperature difference index was constructed and taken as an indicator for the happening of low-temperature and frost damage during fruit enlargement period for tomato in greenhouse.Additionally,a temperature forecasting model was constructed through a regression analysis method. The results show that the occurrence of low-temperature and frost damage for tomato in greenhouse can be attribu-ted to the combined effects of continuous low temperature,lack of sunshine and high humidity in greenhouse.Low-temperature and frost damage happens when the number of scant-sunshine days with rain or snow outside green-house is more than 3,the maximum temperature in greenhouse is less than 10 ℃,the minimum temperature is less than 5 ℃,and the duration of low temperature (less than 5 ℃)is more than 15 h.In this study,hourly temperature data inside and outside greenhouse are used to construct a temperature forecasting model on an hourly time step for greenhouse.The forecasting accuracy for hourly temperature with an absolute error ≤3 ℃ from 1 8:00 to 08:00 reaches more than 86%.Based on the low-temperature and frost damage indicators and the hourly temperature forecasting model,an early warning for occurrence of low-temperature and frost damages can be provided.It im-proves the disaster prevention and mitigation capabilities in a greenhouse.
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