{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T14:22:27Z","timestamp":1782742947534,"version":"3.54.5"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T00:00:00Z","timestamp":1675814400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"International Cooperation Project from the Ministry of Science and Technology of China","award":["2017YFE0130500"],"award-info":[{"award-number":["2017YFE0130500"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Agricultural droughts cause a great reduction in winter wheat productivity; therefore, timely and precise irrigation recommendations are needed to alleviate the impact. This study aims to assess drought stress in winter wheat with the use of an unmanned aerial system (UAS) with multispectral and thermal sensors. High-resolution Water Deficit Index (WDI) maps were derived to assess crop drought stress and evaluate winter wheat actual evapotranspiration rate (ETa). However, the estimation of WDI needs to be improved by using more appropriate vegetation indices as a proximate of the fraction of vegetation cover. The experiments involved six irrigation levels of winter wheat in the harvest years 2019 and 2020 at Luancheng, North China Plain on seasonal and diurnal timescales. Additionally, WDI derived from several vegetation indices (VIs) were compared: near-infrared-, red edge-, and RGB-based. The WDIs derived from different VIs were highly correlated with each other and had similar performances. The WDI had a consistently high correlation to stomatal conductance during the whole season (R2 between 0.63\u20130.99) and the correlation was the highest in the middle of the growing season. On the contrary, the correlation between WDI and leaf water potential increased as the season progressed with R2 up to 0.99. Additionally, WDI and ETa had a strong connection to soil water status with R2 up to 0.93 to the fraction of transpirable soil water and 0.94 to the soil water change at 2 m depth at the hourly rate. The results indicated that WDI derived from multispectral and thermal sensors was a reliable factor in assessing the water status of the crop for irrigation scheduling.<\/jats:p>","DOI":"10.3390\/s23041903","type":"journal-article","created":{"date-parts":[[2023,2,8]],"date-time":"2023-02-08T05:37:31Z","timestamp":1675834651000},"page":"1903","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Spatiotemporal Winter Wheat Water Status Assessment Improvement Using a Water Deficit Index Derived from an Unmanned Aerial System in the North China Plain"],"prefix":"10.3390","volume":"23","author":[{"given":"Vita","family":"Antoniuk","sequence":"first","affiliation":[{"name":"Department of Agroecology, Aarhus University, Blichers All\u00e9 20, 8830 Tjele, Denmark"},{"name":"Sino-Danish College (SDC), University of Chinese Academy of Sciences, Eastern Yanqihu Campus, 380 Huaibeizhuang, Huairou, Beijing 101400, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2850-502X","authenticated-orcid":false,"given":"Xiying","family":"Zhang","sequence":"additional","affiliation":[{"name":"Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3845-4465","authenticated-orcid":false,"given":"Mathias Neumann","family":"Andersen","sequence":"additional","affiliation":[{"name":"Department of Agroecology, Aarhus University, Blichers All\u00e9 20, 8830 Tjele, Denmark"},{"name":"Sino-Danish College (SDC), University of Chinese Academy of Sciences, Eastern Yanqihu Campus, 380 Huaibeizhuang, Huairou, Beijing 101400, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kirsten","family":"K\u00f8rup","sequence":"additional","affiliation":[{"name":"Department of Agroecology, Aarhus University, Blichers All\u00e9 20, 8830 Tjele, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2068-3040","authenticated-orcid":false,"given":"Kiril","family":"Manevski","sequence":"additional","affiliation":[{"name":"Department of Agroecology, Aarhus University, Blichers All\u00e9 20, 8830 Tjele, Denmark"},{"name":"Sino-Danish College (SDC), University of Chinese Academy of Sciences, Eastern Yanqihu Campus, 380 Huaibeizhuang, Huairou, Beijing 101400, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,8]]},"reference":[{"key":"ref_1","unstructured":"United Nations Office for Disaster Risk Reduction (2021). 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