用自动盘式吸渗仪测定土壤导水率

盘式吸渗仪已成为测定田间土壤水力参数的重要工具之一，自动监测装置的应用将进一步提高试验的精确度并加快试验进程。该文介绍了一种试验装置，通过连接在储水管上下两端的传感器实时压差监测，以此确定入渗水量的变化过程，并通过一系列试验，对试验装置的可靠性进行了验证，将试验装置应用到实际测定土壤水力参数中。试验结果表明：自动监测装置通过测定储水管的压差，并通过相应关系代换为储水管水位变化来采集试验数据的方法是可靠的。通过与人工读数方法测定的结果对比表明，其精度可以达到试验要求；对于本试验土壤，用自动监测装置采集的数据来确定吸渗率的时间可以控制在30 s～4 min之间。

Measurement of soil conductivity by automated disc tension infiltrometer

Disc tension infiltrometer has been an important method for measuring the soil hydraulic parameters, and the application of auto mechanism can improve the precision meanwhile. The automation of disc tension infiltrometer was developed. Pressure transducer was used to record the chenges of water level. The automation of disc tension infiltrometer was proved to be credible through indoor experiments and was applied to measure soil hydraulic parameters. Results show that pressure difference in the reservoir measured by auto mechanism is replaced by the change of water level in the reservoir to observe the experimental data. The method is feasible. Compared with the result measured by reading manually, the accuracy of automated disc tension infiltrometer reaches the test requirement. The time scale of determining the sorptivity can be set to 30 second to 4 minutes for the experimental soil.