Laboratory calibration of soil moisture sensors in porous media (repacked soils) v1 (protocols.io.pjidkke)

Proper characterization of contaminants in subsurface helps to clean up effectively the contaminated sites. In this study, different methods were used to quantify non-volatile light non-aqueous phase liquid (LNAPL) and water from sample columns subjected to different water to LNAPL ratios. The objective of the study was to evaluate methods for porous media water and LNAPL contents analysis. The liquids were sampled from the sample columns using activated carbon pellets (ACP). Sample columns water content was also measured using soil moisture sensors. Dielectric mixing model (DMM) was evaluated for the estimation of LNAPL content after water and LNAPL contents of the sample columns were determined through gravimetric analysis method. The result shows that it was possible to sample both water and LNAPL using ACP proportionally but with high standard deviations. It also shows that more liquid was sampled from sample columns subjected to only one liquid compared to sample columns subjected to two liquids. On the other hand, analysis of water and LNAPL using gravimetric analysis method gave the best result although the presence of LNAPL resulted in underestimation of water content at higher LNAPL contents. Meanwhile, the presence of LNAPL modified the bulk relative permittivity (ε<sub>a</sub>) of the sample columns and resulted in overestimation of water contents measured using soil moisture sensors at higher LNAPL content. The modification of ε<sub>a</sub> was used for the estimation of LNAPL using DMM. The evaluation of the model with known water and LNAPL contents and in estimating the LNAPL content of the other sample columns shows that the model could be used for the proper estimation of LNAPL in porous media.

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Approaches to calibrate in-situ capacitance soil moisture sensors and some of their implications

10.5194/soil-2016-40 ◽

2016 ◽

Cited By ~ 2

Author(s):

N. A. L. Archer ◽

B. R. Rawlins ◽

B. P. Machant ◽

J. D. Mackay ◽

P. I. Meldrum

Keyword(s):

Soil Moisture ◽

Field Measurements ◽

Soil Cores ◽

Undisturbed Soil ◽

Soil Moisture Sensors ◽

Soil Sensors ◽

Laboratory Calibration ◽

Rain Events ◽

Undisturbed Soil Cores

Abstract. Capacitance probes are increasingly being used to monitor volumetric water content (VWC) in field conditions and are provided with in-built factory calibrations so they can be deployed at a field site without the requirement for local calibration. These calibrations may not always have acceptable accuracy and therefore to improve the accuracy of such calibrations soil-specific laboratory or field calibrations are required. In some cases, manufacturers suggest calibration is undertaken on soil in which the structure has been removed (through sieving or grinding), whilst in other cases manufacturers suggest structure may be retained. The objectives of this investigation were to (i) demonstrate the differences in laboratory calibration of the sensors using both structured and unstructured soils, (ii) compare moisture contents at a range of suctions with those predicted from soil moisture release curves for their texture classes (iii) compare the magnitude of errors for field measurements of soil moisture based on the original factory calibrations and the laboratory-based calibrations using structured soil. Grinding and sieving clay soils to 50 % water to the ground and sieved soil samples, dielectric values to VWC > 50 % were observed to be significantly lower than using undisturbed soil cores taken from the field and therefore undisturbed soil cores were considered to be better to calibrate capacitance probes. Generic factory calibrations for most soil sensors have a range of measurement from 0 to 50 %, which is not appropriate for the studied clay-rich soil, where ponding can occur during persistent rain events, which are common in temperate regions.

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Performance of soil moisture sensors in gypsiferous and salt-affected soils

Biosystems Engineering ◽

10.1016/j.biosystemseng.2021.07.006 ◽

2021 ◽

Vol 209 ◽

pp. 200-209

Author(s):

Adil K. Salman ◽

Saad E. Aldulaimy ◽

Huthaifa J. Mohammed ◽

Yaareb M. Abed

Keyword(s):

Soil Moisture ◽

Soil Moisture Sensors ◽

Salt Affected Soils

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Modeling Soil Moisture and Flow Dynamics of Variably Saturated Heterogeneous Lateritic Porous Media under Wheat Crop

Journal of Irrigation and Drainage Engineering ◽

10.1061/(asce)ir.1943-4774.0001621 ◽

2021 ◽

Vol 147 (11) ◽

pp. 04021049

Author(s):

Smaranika Mahapatra ◽

Madan K. Jha

Keyword(s):

Porous Media ◽

Soil Moisture ◽

Flow Dynamics ◽

Wheat Crop

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Design a Monitoring and Control in Irrigation Systems using Arduino Wemos with the Internet of Things

Journal of Integrated and Advanced Engineering (JIAE) ◽

10.51662/jiae.v1i1.13 ◽

2021 ◽

Vol 1 (1) ◽

pp. 53-64

Author(s):

Lukman Medriavin Silalahi ◽

Setiyo Budiyanto ◽

Freddy Artadima Silaban ◽

Arif Rahman Hakim

Keyword(s):

Soil Moisture ◽

Water Level ◽

Irrigation System ◽

Ground Level ◽

Prototype System ◽

Monitoring And Control ◽

Moisture Sensor ◽

Turn On ◽

Soil Moisture Sensors ◽

Level Sensor

Irrigation door is a big issue for farmers. The factor that became a hot issue at the irrigation gate was the irresponsible attitude of the irrigation staff regarding the schedule of opening/closing the irrigation door so that it caused the rice fields to becoming dry or submerged. In this research, an automatic prototype system for irrigation system will be designed based on integrating several sensors, including water level sensors, soil moisture sensors, acidity sensors. This sensor output will be displayed on Android-based applications. The integration of communication between devices (Arduino Nano, Arduino Wemos and sensors supporting the irrigation system) is the working principle of this prototype. This device will control via an Android-based application to turn on / off the water pump, to open/close the irrigation door, check soil moisture, soil acidity in real time. The pump will automatically turn on based on the water level. This condition will be active if the water level is below 3cm above ground level. The output value will be displayed on the Android-based application screen and LCD screen. Based on the results of testing and analysis of the prototype that has been done in this research, the irrigation door will open automatically when the soil is dry. This condition occurs if the water level is less than 3 cm. The calibrated Output value, including acidity sensor, soil moisture sensor and water level sensor, will be sent to the server every 5 seconds and forwarded to an Android-based application as an output display.

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Interpolation and 3D visualization of soil moisture

Landscape & Environment ◽

10.21120/le/11/1/3 ◽

2017 ◽

Vol 11 (1) ◽

pp. 23-34

Author(s):

András Hervai ◽

Ervin Pirkhoffer ◽

Szabolcs Ákos Fábián ◽

Ákos Halmai ◽

Gábor Nagy ◽

...

Keyword(s):

Soil Moisture ◽

Cross Sections ◽

3D Visualization ◽

Temporal Changes ◽

Adaptation To Climate Change ◽

Soil Moisture Sensors ◽

Average Maximum ◽

Moisture Conditions ◽

2D And 3D ◽

Soil Moisture Measurement

Adaptation to climate change demands the optimal and sustainable water management in agriculture, with an inevitable focus on soil moisture conditions. In the current study we developed an ArcGIS 10.4. platform-based application (software) to model spatial and temporal changes in soil moisture in a soy field. Six SENTEK Drill & Drop soil moisture sensors were deployed in an experimental field of 4.3 hectares by the contribution of Elcom Ltd. Soil moisture measurement at each location were taken at six depths (5, 15, 25, 35, 45 and 55 cm) in 60-minute intervals. The model is capable to spatially interpolate monitored soil moisture using the technique. The time sequence change of soil moistures can be tracked by a Time Slider for both the 2D and 3D visualization. Soil moisture temporal changes can be visualized in either daily or hourly time intervals, and can be shown as a motion figure. Horizon average, maximum and minimum values of soil moisture data can be identified with the builtin tool of ArcGIS. Soil moisture spatial distribution can be obtained and plotted at any cross sections, whereas an alarm function has also been developed for tension values of 250, 1,000 and 1,500 kPa.

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