基于不同发育期的日光温室黄瓜低温冷害风险评估研究

文章基于自然灾害风险理论对天津日光温室黄瓜低温冷害进行风险评估。以温室内、外气象观测数据为基础,以天津设施农业种植区为研究区域,通过以往积累的观测试验结果与实地调查,确定不同发育期黄瓜低温冷害温室内致灾指标,并使用80%保证率法,由温室内致灾指标推算温室外致灾指标;基于自然灾害风险理论,估算日光温室黄瓜低温冷害风险概率;并实现基于不同发育期的温室黄瓜低温冷害风险评估与区划。研究结果表明,(1)就不同发育期而言,近10年来,苗期黄瓜遭受轻度低温冷害的风险明显高于中度与重度低温冷害,花期黄瓜遭受轻度与中度低温冷害的风险普遍高于重度低温冷害,果期黄瓜遭受重度低温冷害的风险普遍较高;就黄瓜生长整个生育期而言,大部分越冬茬黄瓜果期遭受重度低温冷害的风险普遍较高,这给黄瓜最终产量与经济收入带来较大影响,而越冬茬黄瓜苗期发生重度低温冷害的风险最低;(2)就空间分布而言,果期重度低温冷害的风险全天津最高,黄瓜苗、花、果期遭受轻度低温冷害的风险也较高,而黄瓜苗期遭受重度灾害的风险最低;(3)宝坻西北部与蓟县西南部边缘在各生育期不同受灾等级下都会成为高风险区,这是由于该区地势低洼,冷空气下沉,易造成低温所致。

ESTIMATION OF LOW TEMPERATURE DISASTER RISK OF SOLAR GREENHOUSE CUCUMBERS BASED ON DIFFERENT GROWTH-DEVELOPMENT STAGES

The low temperature disaster risk of solar greenhouse cucumbers in Tianjin was estimated based on natural disaster risk theory. The low temperature disaster indexes were determined using the meteorological data of insidesolar greenhouse obtained from the observation, test and fieldwork. And the low temperature disaster indexes of outside the solar greenhouse were determined based on 80% guarantee rate method. According to natural disaster risk estimation theory, the risk probability of low temperature disaster of solar greenhouse cucumbers was estimated, and the different grade risk regions were divided based on different growth-development phase. The study results showed that (1) In terms of different growth-development stages, in recent 10 years, the cold damage risk caused by the mild low temperature was obviously higher than that by the moderate and severe low temperature during cucumber seeding stage. Both the risks caused by the mild and moderate low temperature were higher than that by the severe low temperature during the flowering phase. The severe low temperature risk was generally high during fruiting stage. With respect to the whole growth-development stage, most overwintering greenhouse cucumbers suffered obvious severe low temperature damage risk during fruiting stage, which had an important impact on the ultimate yield and economic income of greenhouse cucumbers. The severe low temperature risk of the overwintering cucumbers during seeding stage was the lowest. (2) In terms of the space distribution of chilling damage risk, the severe chilling damage risk during fruiting stage was the highest, and the mild risk was higher during the seeding, flowering and fruiting stages. (3)Because the cold air can sink to the low-lying area, and easily lead to the low temperature, the northwest of Baodi district and southwest of Jixian were the regions that always beard higher disaster risk at different growth-development stages and different disaster levels.