The determination of the volumetric soil water content θ_v by means of capacitive profile probes is often applied to investigate the soil water storage change ΔS that serves as basis for decisions in agricultural water management. The soil properties have a big effect on the accuracy of the θ_v measurements. The use of only one calibration function, often provided by the manufacturers of the probes, cannot fulfil the requirements of all site conditions. Therefore, many individual calibration functions have in the past been determined for different soils and sensors. A literature review of existing calibration functions of the capacitive profile probe Diviner 2000 shows the broad range of available functions. The review makes it clear that there is a lack of functions for organic soils. These soils are typical soils of wet sites with shallow groundwater tables. The soil moisture is of big importance for many ecological processes of these sites and therefore an exact determination of θ_v is important. A Diviner 2000 profile probe was calibrated on such a shallow groundwater site in a classic field calibration procedure and the determined functions were applied to the soil profile of a weighable groundwater lysimeter. The soil water storage change ΔS was estimated with the measured θ_v values and compared with the measured mass change Δm of the lysimeter. The mean error (bias) between ΔS with the field calibration function and Δm was 7.8 kg and the root mean squared error (RMSE) 19.9 kg. An iterative adaptation of the calibration functions to the measured Δm values of the lysimeter reduced the bias to 0.9 kg and the RMSE to 14.0 kg. The investigations illustrate the problems of a classic field calibration under the conditions of a shallow groundwater site with low θ_v changes in deeper soil horizons and soils with high C_org contents as well as the inaccuracy in the determination of ΔS based on θ_v measurements with capacitive profile probes.

通常利用电容分布探头确定土壤含水量_θv，以调查土壤蓄水量变化ΔS，作为农业水管理决策的基础。土壤性质对_θv的精度影响很大测量。通常仅由探头制造商提供的一种校准功能无法满足所有现场条件的要求。因此，过去已经针对不同的土壤和传感器确定了许多单独的校准功能。对电容分布探头Diviner 2000的现有校准功能的文献综述显示了广泛的可用功能。审查清楚表明有机土壤缺乏功能。这些土壤是地下水位较浅的潮湿地区的典型土壤。对于这些地点的许多生态过程而言，土壤湿度至关重要，因此要精确确定_θv很重要 在经典的现场校准程序中，在如此浅的地下水位上对Diviner 2000剖面探头进行了校准，并将确定的功能应用于可称量的地下水溶渗仪的土壤剖面。用测得的_θv值估算土壤储水量变化ΔS ，并将其与测渗仪的测得的质量变化Δm进行比较。具有现场校准功能的ΔS与Δm之间的平均误差（bias）为7.8 kg，均方根误差（RMSE）为19.9 kg。校准函数对测渗仪的Δm值进行迭代调整，可将偏差降低到0.9千克，将RMSE降低到14.0千克。研究表明，在_θv低的地下水浅埋场条件下，经典场标定存在一些问题。较深的土壤层和高C _org含量的土壤的变化以及基于基于电容轮廓探头的_θv测量值确定ΔS的不准确性。