Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard
Unmanned aerial vehicle (UAV) remote sensing has become a readily usable tool for agricultural water management with high temporal and spatial resolutions. UAV-borne thermography can monitor crop water status near real-time, which enables precise irrigation scheduling based on an accurate decision-m...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-07-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/13/14/2775 |
| _version_ | 1797526157990559744 |
|---|---|
| author | Suyoung Park Dongryeol Ryu Sigfredo Fuentes Hoam Chung Mark O’Connell Junchul Kim |
| author_facet | Suyoung Park Dongryeol Ryu Sigfredo Fuentes Hoam Chung Mark O’Connell Junchul Kim |
| author_sort | Suyoung Park |
| collection | DOAJ |
| description | Unmanned aerial vehicle (UAV) remote sensing has become a readily usable tool for agricultural water management with high temporal and spatial resolutions. UAV-borne thermography can monitor crop water status near real-time, which enables precise irrigation scheduling based on an accurate decision-making strategy. The crop water stress index (CWSI) is a widely adopted indicator of plant water stress for irrigation management practices; however, dependence of its efficacy on data acquisition time during the daytime is yet to be investigated rigorously. In this paper, plant water stress captured by a series of UAV remote sensing campaigns at different times of the day (9h, 12h and 15h) in a nectarine orchard were analyzed to examine the diurnal behavior of plant water stress represented by the CWSI against measured plant physiological parameters. CWSI values were derived using a probability modelling, named ‘Adaptive CWSI’, proposed by our earlier research. The plant physiological parameters, such as stem water potential (<i>ψ<sub>stem</sub></i>) and stomatal conductance (<i>g<sub>s</sub></i>), were measured on plants for validation concurrently with the flights under different irrigation regimes (0, 20, 40 and 100 % of ETc). Estimated diurnal CWSIs were compared with plant-based parameters at different data acquisition times of the day. Results showed a strong relationship between <i>ψ<sub>stem</sub></i> measurements and the CWSIs at midday (12 h) with a high coefficient of determination (R<sup>2</sup> = 0.83). Diurnal CWSIs showed a significant R<sup>2</sup> to <i>g<sub>s</sub></i> over different levels of irrigation at three different times of the day with R<sup>2</sup> = 0.92 (9h), 0.77 (12h) and 0.86 (15h), respectively. The adaptive CWSI method used showed a robust capability to estimate plant water stress levels even with the small range of changes presented in the morning. Results of this work indicate that CWSI values collected by UAV-borne thermography between mid-morning and mid-afternoon can be used to map plant water stress with a consistent efficacy. This has important implications for extending the time-window of UAV-borne thermography (and subsequent areal coverage) for accurate plant water stress mapping beyond midday. |
| first_indexed | 2024-03-10T09:25:14Z |
| format | Article |
| id | doaj.art-ff10746c78514b9caa39c06cd1c68633 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-10T09:25:14Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-ff10746c78514b9caa39c06cd1c686332023-11-22T04:52:12ZengMDPI AGRemote Sensing2072-42922021-07-011314277510.3390/rs13142775Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine OrchardSuyoung Park0Dongryeol Ryu1Sigfredo Fuentes2Hoam Chung3Mark O’Connell4Junchul Kim5Department of Infrastructure Engineering, The University of Melbourne, Parkville, VIC 3010, AustraliaDepartment of Infrastructure Engineering, The University of Melbourne, Parkville, VIC 3010, AustraliaDigital Agriculture, Food and Wine Group, School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC 3010, AustraliaDepartment of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, AustraliaAgriculture Victoria Research, Department of Jobs, Precincts and Regions, Tatura, VIC 3616, AustraliaCenter for Data Science, Seoul Institute of Technology, Seoul 03909, KoreaUnmanned aerial vehicle (UAV) remote sensing has become a readily usable tool for agricultural water management with high temporal and spatial resolutions. UAV-borne thermography can monitor crop water status near real-time, which enables precise irrigation scheduling based on an accurate decision-making strategy. The crop water stress index (CWSI) is a widely adopted indicator of plant water stress for irrigation management practices; however, dependence of its efficacy on data acquisition time during the daytime is yet to be investigated rigorously. In this paper, plant water stress captured by a series of UAV remote sensing campaigns at different times of the day (9h, 12h and 15h) in a nectarine orchard were analyzed to examine the diurnal behavior of plant water stress represented by the CWSI against measured plant physiological parameters. CWSI values were derived using a probability modelling, named ‘Adaptive CWSI’, proposed by our earlier research. The plant physiological parameters, such as stem water potential (<i>ψ<sub>stem</sub></i>) and stomatal conductance (<i>g<sub>s</sub></i>), were measured on plants for validation concurrently with the flights under different irrigation regimes (0, 20, 40 and 100 % of ETc). Estimated diurnal CWSIs were compared with plant-based parameters at different data acquisition times of the day. Results showed a strong relationship between <i>ψ<sub>stem</sub></i> measurements and the CWSIs at midday (12 h) with a high coefficient of determination (R<sup>2</sup> = 0.83). Diurnal CWSIs showed a significant R<sup>2</sup> to <i>g<sub>s</sub></i> over different levels of irrigation at three different times of the day with R<sup>2</sup> = 0.92 (9h), 0.77 (12h) and 0.86 (15h), respectively. The adaptive CWSI method used showed a robust capability to estimate plant water stress levels even with the small range of changes presented in the morning. Results of this work indicate that CWSI values collected by UAV-borne thermography between mid-morning and mid-afternoon can be used to map plant water stress with a consistent efficacy. This has important implications for extending the time-window of UAV-borne thermography (and subsequent areal coverage) for accurate plant water stress mapping beyond midday.https://www.mdpi.com/2072-4292/13/14/2775unmanned aerial vehicle (UAV)remote sensingthermal infrared (TIR) imageryadaptive crop water stress index (Adaptive CWSI) |
| spellingShingle | Suyoung Park Dongryeol Ryu Sigfredo Fuentes Hoam Chung Mark O’Connell Junchul Kim Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard Remote Sensing unmanned aerial vehicle (UAV) remote sensing thermal infrared (TIR) imagery adaptive crop water stress index (Adaptive CWSI) |
| title | Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard |
| title_full | Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard |
| title_fullStr | Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard |
| title_full_unstemmed | Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard |
| title_short | Dependence of CWSI-Based Plant Water Stress Estimation with Diurnal Acquisition Times in a Nectarine Orchard |
| title_sort | dependence of cwsi based plant water stress estimation with diurnal acquisition times in a nectarine orchard |
| topic | unmanned aerial vehicle (UAV) remote sensing thermal infrared (TIR) imagery adaptive crop water stress index (Adaptive CWSI) |
| url | https://www.mdpi.com/2072-4292/13/14/2775 |
| work_keys_str_mv | AT suyoungpark dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard AT dongryeolryu dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard AT sigfredofuentes dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard AT hoamchung dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard AT markoconnell dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard AT junchulkim dependenceofcwsibasedplantwaterstressestimationwithdiurnalacquisitiontimesinanectarineorchard |