论文部分内容阅读
为检测所研制的时域传输仪(ti me domain transmission,TDT)测定土壤含水量的性能,通过室内土柱试验,对时域传输仪在3种质地非盐土和滨海盐土上测定土壤含水量的性能进行了评估。结果表明:在一般非盐化的农业土壤和滨海盐土上,土壤体积含水量和TDT输出的电压之间均存在线性关系。在砂土和砂壤土上,可以忽略质地差异和容重因素的影响用统一关系式计算含水量,估计标准误差是0.017cm3/cm3;在壤黏土上容重因素影响明显,应用时需要单独校正,校正后计算含水量的估计标准误差小于0.016cm3/cm3。TDT水分测试仪在盐溶液中浸入深度和输出的电压值始终保持线性关系,且不受溶液电导率的影响。在滨海盐土上,不同容重条件下土壤体积含水量和TDT输出的电压均呈线性关系,且容重因素影响不明显,可以建立统一的含水量校正关系,估计标准误差是0.019cm3/cm3。因此,TDT水分测试仪可以测定一般农业土壤含水量,在盐溶液中具有抗盐分干扰的优良特性,在滨海盐土含水量的测定上也具有很好的适用性。
In order to test the performance of soil moisture content measured by TDT, the soil moisture content of three kinds of soil texture and coastal saline soil was measured by indoor soil column test Performance was evaluated. The results showed that there was a linear relationship between the volumetric water content of soil and the voltage of TDT output in the general non-salinized agricultural soil and coastal saline soil. On sandy and sandy loam soil, the influence of texture difference and bulk density can be neglected. The water content is calculated by the unified relational formula. The estimated standard error is 0.017cm3 / cm3. The influence of bulk density on soil clay is obvious. When applied, it needs to be individually calibrated and corrected After the calculation of the estimated standard deviation of water content is less than 0.016cm3 / cm3. TDT moisture tester immersed in the salt solution depth and output voltage values ?? always maintain a linear relationship, and not affected by the conductivity of the solution. On coastal saline soil, the volumetric water content of soil and the voltage of TDT were linear under different conditions of bulk density, and the influence of bulk density was not obvious. The uniform water content calibration could be established with the estimated standard error of 0.019cm3 / cm3. Therefore, TDT Moisture Tester can determine the general agricultural soil moisture content, salt solution has the excellent characteristics of salt interference, the determination of coastal saline soil has good applicability.