Field Calibrations of Soil Moisture Sensors in a Forested Watershed
Spatially variable soil properties influence the performance of soil water content monitoring sensors. The objectives of this research were to: (i) study the spatial variability of bulk density (ρb), total porosity (θt), clay content (CC), electrical conductivity (EC), and pH in the upper Mākaha Val...
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| Format: | Article |
| Language: | English |
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MDPI AG
2011-06-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/11/6/6354/ |
| _version_ | 1828136512110198784 |
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| author | Samira Fares Ali Fares Farhat Abbas |
| author_facet | Samira Fares Ali Fares Farhat Abbas |
| author_sort | Samira Fares |
| collection | DOAJ |
| description | Spatially variable soil properties influence the performance of soil water content monitoring sensors. The objectives of this research were to: (i) study the spatial variability of bulk density (ρb), total porosity (θt), clay content (CC), electrical conductivity (EC), and pH in the upper Mākaha Valley watershed soils; (ii) explore the effect of variations in ρb and θt on soil water content dynamics, and (iii) establish field calibration equations for EC-20 (Decagon Devices, Inc), ML2x (Delta-T-Devices), and SM200 (Delta-T-Devices) sensors to mitigate the effect of soil spatial variability on their performance. The studied soil properties except pH varied significantly (P < 0.05) across the soil water content monitoring depths (20 and 80 cm) and six locations. There was a linear positive and a linear inverse correlation between the soil water content at sampling and ρb, and between the soil water content at sampling and θt, respectively. Values of laboratory measured actual θt correlated (r = 0.75) with those estimated from the relationship θt = 1 − ρb/ρs, where ρs is the particle density. Variations in the studied soil properties affected the performance of the default equations of the three tested sensors; they showed substantial under-estimations of the actual water content. The individual and the watershed-scale field calibrations were more accurate than their corresponding default calibrations. In conclusion, the sensors used in this study need site-specific calibrations in order to mitigate the effects of varying properties of the highly weathered tropical soils. |
| first_indexed | 2024-04-11T18:05:23Z |
| format | Article |
| id | doaj.art-87684a475c924e8e93508bc890a6564a |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T18:05:23Z |
| publishDate | 2011-06-01 |
| publisher | MDPI AG |
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| spelling | doaj.art-87684a475c924e8e93508bc890a6564a2022-12-22T04:10:21ZengMDPI AGSensors1424-82202011-06-011166354636910.3390/s110606354Field Calibrations of Soil Moisture Sensors in a Forested WatershedSamira FaresAli FaresFarhat AbbasSpatially variable soil properties influence the performance of soil water content monitoring sensors. The objectives of this research were to: (i) study the spatial variability of bulk density (ρb), total porosity (θt), clay content (CC), electrical conductivity (EC), and pH in the upper Mākaha Valley watershed soils; (ii) explore the effect of variations in ρb and θt on soil water content dynamics, and (iii) establish field calibration equations for EC-20 (Decagon Devices, Inc), ML2x (Delta-T-Devices), and SM200 (Delta-T-Devices) sensors to mitigate the effect of soil spatial variability on their performance. The studied soil properties except pH varied significantly (P < 0.05) across the soil water content monitoring depths (20 and 80 cm) and six locations. There was a linear positive and a linear inverse correlation between the soil water content at sampling and ρb, and between the soil water content at sampling and θt, respectively. Values of laboratory measured actual θt correlated (r = 0.75) with those estimated from the relationship θt = 1 − ρb/ρs, where ρs is the particle density. Variations in the studied soil properties affected the performance of the default equations of the three tested sensors; they showed substantial under-estimations of the actual water content. The individual and the watershed-scale field calibrations were more accurate than their corresponding default calibrations. In conclusion, the sensors used in this study need site-specific calibrations in order to mitigate the effects of varying properties of the highly weathered tropical soils.http://www.mdpi.com/1424-8220/11/6/6354/variable soil propertiessoil water contentsensor field calibrationtropical soils |
| spellingShingle | Samira Fares Ali Fares Farhat Abbas Field Calibrations of Soil Moisture Sensors in a Forested Watershed Sensors variable soil properties soil water content sensor field calibration tropical soils |
| title | Field Calibrations of Soil Moisture Sensors in a Forested Watershed |
| title_full | Field Calibrations of Soil Moisture Sensors in a Forested Watershed |
| title_fullStr | Field Calibrations of Soil Moisture Sensors in a Forested Watershed |
| title_full_unstemmed | Field Calibrations of Soil Moisture Sensors in a Forested Watershed |
| title_short | Field Calibrations of Soil Moisture Sensors in a Forested Watershed |
| title_sort | field calibrations of soil moisture sensors in a forested watershed |
| topic | variable soil properties soil water content sensor field calibration tropical soils |
| url | http://www.mdpi.com/1424-8220/11/6/6354/ |
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