围框淹灌仪器法测定土壤田间持水量试验研究

田间持水量是重要的土壤水分常数之一，是开展墒情评价和旱情分析，指导科学灌溉不可缺少的基础信息。传统的土壤田间持水量测定方法操作复杂，给土壤墒情评价带来一定难度。通过将先进的无线土壤测量传感技术与传统的围框淹灌法相结合，提出了一种基于无线传感器的新方法，利用“滑动平均含水量法”和“移动平均法”计算确定土壤田间持水量，并在陕西、北京、吉林和河北不同土壤类型的农田开展验证试验。结果表明，与传统环刀法相比，围框淹灌仪器法测定结果的平均相对误差为4.89%，不同质地土壤上测定结果均比较稳定，两种方法测定的田间持水量随土层深度的变化规律一致。围框淹灌仪器法测定土壤田间持水量具有可靠性和便捷实用性，是土壤墒情监测与评价的有效方法，适宜推广应用。 

Experimental Study on Soil Field Water Capacity Determination by Enclosing Frame Flooding Instrument Method

Field water capacity is one of the important soil moisture constants，and it is the basic information indispensable for carrying out moisture evaluation and drought analysis to guide scientific irrigation.Traditional indoor and outdoor methods for measuring field water capacity are complex to operate，which brings certain difficulties to soil moisture evaluation.By combining advanced wireless soil measurement sensor technology with traditional framed flood irrigation method，a new method based on wireless sensors was proposed，which used“moving average moisture content method”and“moving average method”to calculate and determine soil field capacity.Validation experiments were carried out on farms with different soil types in Shaanxi，Beijing，Jilin and Hebei.Results showed that compared with traditional ring cutting method，average relative error of measurement results of framed submerged irrigation instrument method was 4.89%.The results were relatively stable，field capacity measured by the two methods was consistent with variation of soil depth.The framed submerged irrigation instrument method was reliable，convenient and practical for measuring soil field capacity.It is an effective method for soil moisture monitoring and evaluation and suitable for popularization and application.