土壤水分特征曲线在作物非充分灌溉适宜水分下限确定中的应用  

The Application of Soil Water Characteristic Curve in Determination of Lower Limit of Suitable Soil Moisture in Crop Non-sufficient Irrigation

作　　者：刘超[1] 汪有科[1] 张立强[1] 

机构地区：[1]中国科学院水利部水土保持研究所

出　　处：《灌溉排水学报》2007年第6期76-78,共3页Journal of Irrigation and Drainage

基　　金：陕西省科技攻关项目(2006kz08-G3)

摘　　要：SPAC系统中水总是从水势高处流向水势低处,土壤水势的高低是影响植物根系吸水速率的主要因素。相对于土壤含水量来说,用土壤水势作作物非充分灌溉的下限指标更具科学性,更利于水分下限指标的推广应用。试验结果表明,对于整个生育期来说,-200 kPa是比较适宜的大棚番茄土壤水势下限。在这一指标的推广过程中,须先测定当地土壤水分特征曲线,并从曲线上找出该适宜水势对应的土壤含水量,通过控制土壤含水量达到控制土壤水势的目的,从而实现精量灌溉。Water always flows from higher water potential to the lower one in SPAC system. And water potential is the main element that influences the plant water uptake rate. Compared with the soil water content, it will be much more scientific to use the soil water potential as the lowest limit index of crop non-sufficient irrigation and be easier to be applied and extended. The experimental results show that -200 kPa is a more suitable lower limit of soil water potential to the tomato in greenhouse. During application of the above index, the soil water characteristic curve must be determined and then find out the corresponding soil water content of the water potential. Finally through controlling of soil water content to control the soil water potential and then realizes precise irrigation.

关 键 词：水分特征曲线 非充分灌溉 土水势 水分下限 土壤含水率 

分 类 号：S274[农业科学—农业水土工程]