摘要
以田间试验实测资料为基础,通过计算有膜和无膜滴灌条件下土壤含水率占田间持水率的百分比,评价了土壤湿润的有效区域,并进一步与滴灌土壤湿润比的工程设计值进行比较,从而验证了在工程设计中选取的土壤湿润比是否满足作物对土壤水分的需求。结果表明,地膜覆盖条件下,其土壤湿润比高于无膜滴灌条件下的土壤湿润比,由于地膜在一定程度上降低了土壤的蒸发作用,从而使得其土壤湿润体大于无膜滴灌。无膜滴灌低水处理实测的田间土壤湿润比较设计值低0.28,不符合设计要求;覆膜滴灌高水处理土壤湿润比的实测值较设计值高0.27,虽然符合设计要求,但其没有达到滴灌节水的目的。其次,利用土壤适宜含水率指标评价土壤有效湿润区范围,能在一定程度上体现出土壤湿润区与玉米灌水定额之间的关系。
Based on the measured data in the field,soil available wetted area was evaluated by calculating the actual and theoretical values of wetted percentage under mulched drip irrigation（MDI）and drip irrigation（DI）,which were compared with the designed values in order to verify whether the designing theoretical value of wetted percentage would be suitable for crop.Results showed that,when the field surface was mulched by plastic film,the whole mulched area of field was irrigated,and the ratio of soil wetted area under MDI was larger than that under DI.The plastic film reduced the evaporation,which made the ratio higher than that under DI.In this experiment,wetted percentage under DI in the low water experimental plot was 0.28 lower than the designed value,which did not meet the requirements.Wetted percentage under MDI in the case of high water experimental plot was 0.27 higher than the theoretical value,although it met the requirements,it did not achieve the good of saving water.In addition,the index of soil available moisture（ISAM）was used to assess the soil wetting pattern to clearly express the relationships between soil wetting pattern and crop water consumption.Thus,the ISAM could be usable for designing the ratio of soil wetted percentage.
出处
《灌溉排水学报》
CSCD
北大核心
2015年第12期89-92,共4页
Journal of Irrigation and Drainage
基金
"十二五"国家科技支撑计划课题(2014BAD12B03)
关键词
滴灌
土壤湿润比
田间试验
drip irrigation
soil wetted percentage
experiment
