河西东部设施农业低温灾害风险分析

Low Temperature Risk Evaluation for Facility Agriculture in Eastern Hexi Corridor of Gansu

依托典型棚监测数据和1980—2014年6个气象站观测资料,利用信息扩散理论对设施农业低温灾害进行分析。结果表明:温棚作物可遭冻害的最低温度,黄瓜为-17.5℃、番茄为-14.5℃。极端最低温度强度大、频率高、覆盖范围广、变化幅度大,极易诱发冻害。在同一级别下最低温度频次为凉州<古浪<民勤<永昌<乌鞘岭<天祝;在不同等级上最低温度强度为凉州<古浪<民勤<永昌<天祝<乌鞘岭。研究区域在-15^-33℃均有一定风险,乌鞘岭山地的风险值高于中部绿洲区和北部荒漠区,北部荒漠区高于中部绿洲区。从风险指数分布上看古浪、凉州为轻度风险,民勤、永昌为中度风险,天祝、乌鞘岭为重度风险。该结论可为本地设施农业生产布局和气候资源利用提供科学依据。

Based on the monitoring data of typical greenhouse and the observation data of 6 weather stationsfrom 1980 to 2014 in eastern Hexi corridor, the authors used information diffusion theory and risk assessmentmethod to analyze the freezing damage caused by low temperature on facility agriculture. The results showedthat the low temperature had great influence on greenhouse crops. When the outside temperature of thegreenhouse was minus 17.5℃ and minus 14.5℃, the cucumber and tomato would suffer freezing damage. Thecharacteristics of extreme minimum temperature were high intensity, high frequency, wide covering range,great amplitude of variation, and easily inducing freezing damage. At the same level, the frequency of thelowest temperature appeared in an order from small to large as： Liangzhou, Gulang, Minqin, Yongchang,Wushoaling, Tianzhu. For different levels, the strength of the lowest temperature from small to large was in anorder as： Liangzhou, Gulang, Minqin, Yongchang, Tianzhu, Wushaoling. There was a certain risk in the studyarea from minus 15℃ to minus 33℃, the lowest temperature risk value of the Wushaoling mountain was higherthan that in the central part of the oasis and the northern desert, and the lowest temperature risk value of thenorthern desert area was higher than that in the central part of the oasis. As for the risk index distribution, riskindexes of Liangzhou and Gulang were mild, the risk indexes of Minqin and Yongchang were moderate, whilethe risk indexes of Tianzhu and Wushaoling were high. The conclusion can provide scientific basis for theproduction layout of the local facility agriculture and the utilization of climatic resources.