Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees
Time-domain reflectometry (TDR) is an electromagnetic technique that measures the dielectric permittivity (K) which is a surrogate property influenced by water content. Advances in nanoelectronics have enabled the development of a TDR probe (TDR-305 N) to monitor changes in K, bulk electrical conduc...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2024-03-01
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| Series: | Smart Agricultural Technology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2772375524000339 |
| _version_ | 1797246771915653120 |
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| author | María R. Conesa Juan Vera Wenceslao Conejero Virginia Hernandez-Santana María Carmen Ruiz-Sánchez |
| author_facet | María R. Conesa Juan Vera Wenceslao Conejero Virginia Hernandez-Santana María Carmen Ruiz-Sánchez |
| author_sort | María R. Conesa |
| collection | DOAJ |
| description | Time-domain reflectometry (TDR) is an electromagnetic technique that measures the dielectric permittivity (K) which is a surrogate property influenced by water content. Advances in nanoelectronics have enabled the development of a TDR probe (TDR-305 N) to monitor changes in K, bulk electrical conductivity (ECbulk) and temperature (T) in a porous medium, such as a tree trunk. The main objective of this study was to assess the effectiveness of the TDR-305 N sensors for real-time monitoring changes in water content in the trunk of nectarine trees. Throughout the summer of 2022, irrigation was automatically managed with threshold values of soil water content (θv-soil) measured with capacitance probes. Different management allowed depletion (MAD) values were set to trigger irrigation: 50 % in July (moderate water deficit), 100 % in August (severe water deficit), and recovery to well-irrigated conditions in September. Discrete measurements of midday stem water potential (Ψs,md) and leaf gas exchange were made frequently. The results showed a progressive reduction of the measured physiological parameters, as well as of K and ECbulk and θv-soil decreased. Notably, Ψs,md reached a critically low value of -2.03 MPa, coinciding with pronounced and severe stomatal closure. Both K and Ψs,md, were able to explain the variations of θv-soil by more than 75 %. Daily, a positive relationship of K and ECbulk was observed, although ECbulk exhibited a stronger dependence on Ttrunk compared to K. Furthermore, K did not return to its initial values prior to the onset of water stress, possibly influenced by xylem cavitation and a reduction in leaf area during its senescence stage. The findings suggest that trunk permittivity measurements obtained using TDR-305 N sensors could be a reliable indicator for monitoring tree water status. However, further research is needed to determine the threshold values of trunk water content under non-limiting soil water conditions for accurate irrigation scheduling. |
| first_indexed | 2024-04-24T19:48:06Z |
| format | Article |
| id | doaj.art-0c7d502310834a769e931af4c46e2fb7 |
| institution | Directory Open Access Journal |
| issn | 2772-3755 |
| language | English |
| last_indexed | 2024-04-24T19:48:06Z |
| publishDate | 2024-03-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Smart Agricultural Technology |
| spelling | doaj.art-0c7d502310834a769e931af4c46e2fb72024-03-25T04:18:19ZengElsevierSmart Agricultural Technology2772-37552024-03-017100428Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit treesMaría R. Conesa0Juan Vera1Wenceslao Conejero2Virginia Hernandez-Santana3María Carmen Ruiz-Sánchez4Irrigation Department, Consejo Superior de Investigaciones Científicas (CSIC) Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Campus de Espinardo, 25, 30100, Murcia, Spain; Corresponding author.Irrigation Department, Consejo Superior de Investigaciones Científicas (CSIC) Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Campus de Espinardo, 25, 30100, Murcia, SpainIrrigation Department, Consejo Superior de Investigaciones Científicas (CSIC) Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Campus de Espinardo, 25, 30100, Murcia, SpainIrrigation and Ecophysiology Group & Laboratory of Plant Molecular Ecophysiology. Instituto de Recursos Naturales y Agrobiología (IRNAS-CSIC), Avda Reina Mercedes, 10, 41012, Sevilla, SpainIrrigation Department, Consejo Superior de Investigaciones Científicas (CSIC) Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Campus de Espinardo, 25, 30100, Murcia, SpainTime-domain reflectometry (TDR) is an electromagnetic technique that measures the dielectric permittivity (K) which is a surrogate property influenced by water content. Advances in nanoelectronics have enabled the development of a TDR probe (TDR-305 N) to monitor changes in K, bulk electrical conductivity (ECbulk) and temperature (T) in a porous medium, such as a tree trunk. The main objective of this study was to assess the effectiveness of the TDR-305 N sensors for real-time monitoring changes in water content in the trunk of nectarine trees. Throughout the summer of 2022, irrigation was automatically managed with threshold values of soil water content (θv-soil) measured with capacitance probes. Different management allowed depletion (MAD) values were set to trigger irrigation: 50 % in July (moderate water deficit), 100 % in August (severe water deficit), and recovery to well-irrigated conditions in September. Discrete measurements of midday stem water potential (Ψs,md) and leaf gas exchange were made frequently. The results showed a progressive reduction of the measured physiological parameters, as well as of K and ECbulk and θv-soil decreased. Notably, Ψs,md reached a critically low value of -2.03 MPa, coinciding with pronounced and severe stomatal closure. Both K and Ψs,md, were able to explain the variations of θv-soil by more than 75 %. Daily, a positive relationship of K and ECbulk was observed, although ECbulk exhibited a stronger dependence on Ttrunk compared to K. Furthermore, K did not return to its initial values prior to the onset of water stress, possibly influenced by xylem cavitation and a reduction in leaf area during its senescence stage. The findings suggest that trunk permittivity measurements obtained using TDR-305 N sensors could be a reliable indicator for monitoring tree water status. However, further research is needed to determine the threshold values of trunk water content under non-limiting soil water conditions for accurate irrigation scheduling.http://www.sciencedirect.com/science/article/pii/S2772375524000339Automatic soil-based irrigation systemDielectric permittivity (k)Management allowed depletion (MAD)volumetric trunk water content (θv-trunk)TDR-305Nvolumetric soil water content (θv-soil) |
| spellingShingle | María R. Conesa Juan Vera Wenceslao Conejero Virginia Hernandez-Santana María Carmen Ruiz-Sánchez Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees Smart Agricultural Technology Automatic soil-based irrigation system Dielectric permittivity (k) Management allowed depletion (MAD) volumetric trunk water content (θv-trunk) TDR-305N volumetric soil water content (θv-soil) |
| title | Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| title_full | Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| title_fullStr | Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| title_full_unstemmed | Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| title_short | Trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| title_sort | trunk dielectric permittivity correlates with irrigation based on soil water content in fruit trees |
| topic | Automatic soil-based irrigation system Dielectric permittivity (k) Management allowed depletion (MAD) volumetric trunk water content (θv-trunk) TDR-305N volumetric soil water content (θv-soil) |
| url | http://www.sciencedirect.com/science/article/pii/S2772375524000339 |
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