昆明地区微喷条件下大白菜耗水规律研究

Water Consumption Law of Chinese Cabbage Under Microspray Irrigation in Kunming Regions

为探索昆明地区大白菜在微喷条件下的耗水规律和节水潜力,在云南省灌溉试验中心站以‘青岛83-1’为试验作物,于2019年7月7日和9月26日播种2茬大白菜,采用当地群众高产种植灌溉经验为水分处理,使用云智能土壤水分仪研究微喷条件下的夏季和秋季大白菜生育期内耗水量和耗水规律。结果表明,2茬大白菜全生育期蒸发蒸腾量为119.23、102.57 mm,日均蒸发蒸腾强度为1.66、1.27 mm/d,其中结球期平均蒸发蒸腾量最高(47.54 mm),苗期平均蒸发蒸腾量最小(2.36 mm)。不同生育期大白菜蒸发蒸腾量表现为结球期>莲座期>采收期>团棵期>苗期。典型日大白菜蒸发蒸腾量变化曲线呈单峰变化,蒸发蒸腾量高值主要集中在11:00—14:00,且出现明显的“午休”现象。大白菜蒸发蒸腾量随土壤深度增加而减少,0~10 cm处蒸发蒸腾量最多,平均占比达到45.25%,30~40 cm处蒸发蒸腾量最小,平均占比为7.74%。根据大白菜不同生育期土壤含水量的适宜区间,2茬大白菜分别存在2次和3次过度灌水情况,如能避免过度灌水,2茬大白菜可分别节水160.0、180.0 m^(3)/hm^(2)。

To explore the water consumption law of Chinese cabbage under microspray irrigation in Kunming regions,using cloud intelligent soil water meter in Yunnan Irrigation Experiment Center Station,the water consumption law of Chinese cabbage during summer and autumn of 2019 year under microspray irrigation was studied by using local planting experience,and the water saving potential in this regions was revealed under microspray irrigation.The results showed that the evapotranspiration of Chinese cabbage were 119.23 and 102.57 mm during the whole growth period,and the average daily evapotranspiration intensity was 1.66 and 1.27 mm/d,in which the average evapotranspiration was the highest in rosette stage,reaching 47.54 mm,and the average evapotranspiration was the smallest in seedling stage,only 2.36 mm.The evapotranspiration of Chinese cabbage in different growth stages showed heading stage>rosette stage>harvesting stage>group tree stage>seedling stage.The curve of evapotranspiration of typical Chinese cabbage showed a single peak change,and the high value of evapotranspiration mainly concentrated in 11:00-14:00,and there was an obviously‘lunch break’phenomenon.The evapotranspiration of Chinese cabbage decreased with the increase of soil depth.The evapotranspiration of Chinese cabbage was the highest at 0-10 cm,the average proportion reached 45.25%,and the lowest at 30-40 cm,the average proportion was 7.74%.According to the suitable range of soil water content in different growth stages of Chinese cabbage,there were two times and three times of over-irrigation respectively in the two crops of Chinese cabbage.Under the condition of avoiding over-irrigation,the two crops of Chinese cabbage could save water by 160.0 m^(3)/hm^(2) and 180.0 m^(3)/hm^(2) respectively.