{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T05:13:08Z","timestamp":1783919588652,"version":"3.55.0"},"reference-count":63,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2019,7,8]],"date-time":"2019-07-08T00:00:00Z","timestamp":1562544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Solar-induced chlorophyll fluorescence (SIF) is regarded as a proxy for photosynthesis in terrestrial vegetation. Tower-based long-term observations of SIF are very important for gaining further insight into the ecosystem-specific seasonal dynamics of photosynthetic activity, including gross primary production (GPP). Here, we present the design and operation of the tower-based automated SIF measurement (SIFSpec) system. This system was developed with the aim of obtaining synchronous SIF observations and flux measurements across different terrestrial ecosystems, as well as to validate the increasing number of satellite SIF products using in situ measurements. Details of the system components, instrument installation, calibration, data collection, and processing are introduced. Atmospheric correction is also included in the data processing chain, which is important, but usually ignored for tower-based SIF measurements. Continuous measurements made across two growing cycles over maize at a Daman (DM) flux site (in Gansu province, China) demonstrate the reliable performance of SIF as an indicator for tracking the diurnal variations in photosynthetically active radiation (PAR) and seasonal variations in GPP. For the O2\u2013A band in particular, a high correlation coefficient value of 0.81 is found between the SIF and seasonal variations of GPP. It is thus concluded that, in coordination with continuous eddy covariance (EC) flux measurements, automated and continuous SIF observations can provide a reliable approach for understanding the photosynthetic activity of the terrestrial ecosystem, and are also able to bridge the link between ground-based optical measurements and airborne or satellite remote sensing data.<\/jats:p>","DOI":"10.3390\/s19133009","type":"journal-article","created":{"date-parts":[[2019,7,8]],"date-time":"2019-07-08T11:02:37Z","timestamp":1562583757000},"page":"3009","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":72,"title":["SIFSpec: Measuring Solar-Induced Chlorophyll Fluorescence Observations for Remote Sensing of Photosynthesis"],"prefix":"10.3390","volume":"19","author":[{"given":"Shanshan","family":"Du","sequence":"first","affiliation":[{"name":"Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7987-037X","authenticated-orcid":false,"given":"Liangyun","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7689-3031","authenticated-orcid":false,"given":"Xinjie","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Guo","sequence":"additional","affiliation":[{"name":"Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"College of Geomatics, Xi\u2019an University of Science and Technology, Xi\u2019an 710054, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaochan","family":"Hu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaoqiang","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yongguang","family":"Zhang","sequence":"additional","affiliation":[{"name":"International Institute for Earth System Sciences, Nanjing University, Nanjing 21002, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"834","DOI":"10.1126\/science.1184984","article-title":"Terrestrial gross carbon dioxide uptake: Global distribution and covariation with climate","volume":"329","author":"Beer","year":"2010","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.rse.2015.06.004","article-title":"Far-red sun-induced chlorophyll fluorescence shows ecosystem-specific relationships to gross primary production: An assessment based on observational and modeling approaches","volume":"166","author":"Damm","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1632","DOI":"10.1002\/2014GL062943","article-title":"Red and far red Sun-induced chlorophyll fluorescence as a measure of plant photosynthesis","volume":"42","author":"Rossini","year":"2015","journal-title":"Geophys. Res. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Frankenberg, C., Fisher, J.B., Worden, J., Badgley, G., Saatchi, S.S., Lee, J.-E., Toon, G.C., Butz, A., Jung, M., and Kuze, A. (2011). New global observations of the terrestrial carbon cycle from GOSAT: Patterns of plant fluorescence with gross primary productivity. Geophys. Res. Lett., 38.","DOI":"10.1029\/2011GL048738"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"301","DOI":"10.5194\/amt-8-301-2015","article-title":"The Orbiting Carbon Observatory (OCO-2): Spectrometer performance evaluation using pre-launch direct sun measurements","volume":"8","author":"Frankenberg","year":"2015","journal-title":"Atmos. Meas. Tech."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2803","DOI":"10.5194\/amt-6-2803-2013","article-title":"Global monitoring of terrestrial chlorophyll fluorescence from moderate-spectral-resolution near-infrared satellite measurements: Methodology, simulations, and application to GOME-2","volume":"6","author":"Joiner","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2589","DOI":"10.5194\/amt-8-2589-2015","article-title":"A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data","volume":"8","author":"Guanter","year":"2015","journal-title":"Atmos. Meas. Tech."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1502","DOI":"10.1016\/j.scib.2018.10.003","article-title":"Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite","volume":"63","author":"Du","year":"2018","journal-title":"Sci. Bull."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1337","DOI":"10.5194\/amt-8-1337-2015","article-title":"Potential of the TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor for the monitoring of terrestrial chlorophyll fluorescence","volume":"8","author":"Guanter","year":"2015","journal-title":"Atmos. Meas. Tech."},{"key":"ref_10","first-page":"10","article-title":"Global retrievals of solar-induced chlorophyll fluorescence with TROPOMI: First results and intersensor comparison to OCO-2","volume":"45","author":"Frankenberg","year":"2018","journal-title":"Geophys. Res. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1016\/j.rse.2012.02.006","article-title":"Retrieval and global assessment of terrestrial chlorophyll fluorescence from GOSAT space measurements","volume":"121","author":"Guanter","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"20130171","DOI":"10.1098\/rspb.2013.0171","article-title":"Forest productivity and water stress in Amazonia: Observations from GOSAT chlorophyll fluorescence","volume":"280","author":"Lee","year":"2013","journal-title":"Proc. R. Soc. B Biol. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Guanter, L., Zhang, Y., Jung, M., Joiner, J., Voigt, M., Berry, J.A., Frankenberg, C., Huete, A.R., Zarco-Tejada, P., and Lee, J.-E. (2014). Global and time-resolved monitoring of crop photosynthesis with chlorophyll fluorescence. Proc. Natl. Acad. Sci. USA, 201320008.","DOI":"10.1073\/pnas.1320008111"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1016\/j.rse.2014.06.022","article-title":"The seasonal cycle of satellite chlorophyll fluorescence observations and its relationship to vegetation phenology and ecosystem atmosphere carbon exchange","volume":"152","author":"Joiner","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3727","DOI":"10.1111\/gcb.12664","article-title":"Estimation of vegetation photosynthetic capacity from space-based measurements of chlorophyll fluorescence for terrestrial biosphere models","volume":"20","author":"Zhang","year":"2014","journal-title":"Glob. Chang. Biol."},{"key":"ref_16","unstructured":"Voigt, M., Guanter, L., Zhang, Y., Walther, S., Kohler, P., and Jung, M. (2014, January 22\u201324). Global Analysis of the Relationship between Canopy-Scale Chlorophyll Fluorescence and GPP. Proceedings of the 5th International Workshop on Remote Sensing of Vegetation Fluorescence, Paris, France."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"eaam5747","DOI":"10.1126\/science.aam5747","article-title":"OCO-2 advances photosynthesis observation from space via solar-induced chlorophyll fluorescence","volume":"358","author":"Sun","year":"2017","journal-title":"Science"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"649","DOI":"10.1016\/j.scitotenv.2017.11.158","article-title":"Opportunities and challenges of applications of satellite-derived sun-induced fluorescence at relatively high spatial resolution","volume":"619\u2013620","author":"Lu","year":"2018","journal-title":"Sci. Total Environ."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1071\/BT07151","article-title":"\u2018Breathing\u2019 of the terrestrial biosphere: Lessons learned from a global network of carbon dioxide flux measurement systems","volume":"56","author":"Baldocchi","year":"2008","journal-title":"Aust. J. Bot."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1016\/j.rse.2005.06.013","article-title":"A multi-scale analysis of dynamic optical signals in a Southern California chaparral ecosystem: A comparison of field, AVIRIS and MODIS data","volume":"103","author":"Cheng","year":"2006","journal-title":"Remote Sens. Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"S376","DOI":"10.5589\/m10-067","article-title":"SpecNet revisited: Bridging flux and remote sensing communities","volume":"36","author":"Gamon","year":"2010","journal-title":"Can. J. Remote Sens."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"043106","DOI":"10.1063\/1.3574360","article-title":"The hyperspectral irradiometer, a new instrument for long-term and unattended field spectroscopy measurements","volume":"82","author":"Meroni","year":"2011","journal-title":"Rev. Sci. Instrum."},{"key":"ref_23","first-page":"13069","article-title":"EUROSPEC: At the interface between remote sensing and ecosystem CO2 flux measurements in Europe","volume":"12","author":"Porcarcastell","year":"2015","journal-title":"Biogeosci. Discuss."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Yang, X., Tang, J., Mustard, J.F., Lee, J.-E., Rossini, M., Joiner, J., Munger, J.W., Kornfeld, A., and Richardson, A.D. (2015). Solar-induced chlorophyll fluorescence correlates with canopy photosynthesis on diurnal and seasonal scales in a temperate deciduous forest. Geophys. Res. Lett., 2015GL063201.","DOI":"10.1002\/2015GL063201"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/j.rse.2015.03.027","article-title":"Continuous and long-term measurements of reflectance and sun-induced chlorophyll fluorescence by using novel automated field spectroscopy systems","volume":"164","author":"Cogliati","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Yang, X., Shi, H., Stovall, A., Guan, K., Miao, G., Zhang, Y., Zhang, Y., Xiao, X., Ryu, Y., and Lee, J.E. (2018). FluoSpec 2-An automated field spectroscopy system to monitor canopy solar-induced fluorescence. Sensors, 18.","DOI":"10.3390\/s18072063"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1029\/2018JG004742","article-title":"Advancing terrestrial ecosystem science with a novel automated measurement system for sun-induced chlorophyll fluorescence for integration with eddy covariance flux networks","volume":"124","author":"Gu","year":"2019","journal-title":"J. Geophys. Res. Biogeosci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"2977","DOI":"10.3390\/rs11050488","article-title":"Diurnal and seasonal variations in chlorophyll fluorescence associated with photosynthesis at leaf and canopy scales","volume":"11","author":"Campbell","year":"2019","journal-title":"Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Sabater, N., Vicent, J., Alonso, L., Verrelst, J., Middleton, E., Porcar-Castell, A., and Moreno, J. (2018). Compensation of oxygen transmittance effects for proximal sensing retrieval of canopy\u2013leaving sun\u2013induced chlorophyll fluorescence. Remote Sens., 10.","DOI":"10.3390\/rs10101551"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Nichol, C., Drolet, G., Porcar-Castell, A., Wade, T., Sabater, N., Middleton, E., MacLellan, C., Levula, J., Mammarella, I., and Vesala, T. (2019). Diurnal and seasonal solar induced chlorophyll fluorescence and photosynthesis in a Boreal scots pine canopy. Remote Sens., 11.","DOI":"10.3390\/rs11030273"},{"key":"ref_31","unstructured":"Zhang, Y., Wang, S., Liu, L., Ju, W., and Zhu, X. (2017). ChinaSpec: A network of SIF observations to bridge flux measurements and remote sensing data. AGU Fall Meeting, American Geophysical Union."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1740","DOI":"10.3390\/s8031740","article-title":"Assessing steady-state fluorescence and PRI from hyperspectral proximal sensing as early indicators of plant stress: The case of ozone exposure","volume":"8","author":"Meroni","year":"2008","journal-title":"Sensors"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Zhou, X., Liu, Z., Xu, S., Zhang, W., and Wu, J. (2016). An automated comparative observation system for sun-induced chlorophyll fluorescence of vegetation canopies. Sensors, 16.","DOI":"10.3390\/s16060775"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"D13","DOI":"10.1029\/2011JD017037","article-title":"Validation of remotely sensed evapotranspiration over the Hai river basin, China","volume":"117","author":"Jia","year":"2012","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"9171","DOI":"10.1080\/01431161.2010.550646","article-title":"Mapping C3 and C4 plant functional types using separated solar-induced chlorophyll fluorescence from hyperspectral data","volume":"32","author":"Liu","year":"2011","journal-title":"Int. J. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/j.jhydrol.2013.02.025","article-title":"Measurements of evapotranspiration from eddy-covariance systems and large aperture scintillometers in the Hai River Basin, China","volume":"487","author":"Liu","year":"2013","journal-title":"J. Hydrol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1007\/s11430-006-8226-1","article-title":"Carbon dioxide exchange and the mechanism of environmental control in a farmland ecosystem in North China plain","volume":"49","author":"Li","year":"2006","journal-title":"Sci. Chin. Ser. D Earth Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1882","DOI":"10.1016\/j.rse.2011.03.011","article-title":"Modeling the impact of spectral sensor configurations on the FLD retrieval accuracy of sun-induced chlorophyll fluorescence","volume":"115","author":"Damm","year":"2011","journal-title":"Remote Sens. Environ."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Liu, X., Guo, J., Hu, J., and Liu, L. (2019). Atmospheric correction for tower-based solar-induced chlorophyll fluorescence observations at O2-A band. Remote Sens., 11.","DOI":"10.3390\/rs11030355"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"10656","DOI":"10.3390\/rs61110656","article-title":"Assessing band sensitivity to atmospheric radiation transfer for space-based retrieval of solar-induced chlorophyll fluorescence","volume":"6","author":"Liu","year":"2014","journal-title":"Remote Sens."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"5180","DOI":"10.1109\/TGRS.2015.2418992","article-title":"Measurement and correction of atmospheric effects at different altitudes for remote sensing of sun-induced fluorescence in oxygen absorption bands","volume":"53","author":"Daumard","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Liu, X., Liu, L., Hu, J., and Du, S. (2017). Modeling the footprint and equivalent radiance transfer path length for tower-based hemispherical observations of chlorophyll fluorescence. Sensors, 17.","DOI":"10.3390\/s17051131"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"306","DOI":"10.1109\/TIM.1975.4314448","article-title":"Fraunhofer line discriminator Mk II\u2013Airborne instrument for precise and standardized ecological luminescence measurement","volume":"24","author":"Plascyk","year":"1975","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_44","unstructured":"McDonald, M., Schepers, J., Tartly, L., Toai, T.V., and Major, D. (2003). Sun-induced fluorescence: A new tool for precision farming. Digital Imaging and Spectral Techniques: Applications to Precision Agriculture and Crop Physiology, American Society of Agronomy Special Publication."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1109\/LGRS.2008.2001180","article-title":"Improved Fraunhofer line discrimination method for vegetation fluorescence quantification","volume":"5","author":"Alonso","year":"2008","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1645","DOI":"10.1109\/LGRS.2015.2417857","article-title":"Improving chlorophyll fluorescence retrieval using reflectance reconstruction based on principal components analysis","volume":"12","author":"Liu","year":"2015","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"10626","DOI":"10.3390\/rs70810626","article-title":"New spectral fitting method for full-spectrum solar-induced chlorophyll fluorescence retrieval based on principal components analysis","volume":"7","author":"Liu","year":"2015","journal-title":"Remote Sens."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"743","DOI":"10.5721\/EuJRS20154841","article-title":"Effects of spectral resolution and SNR on the vegetation solar-induced fluorescence retrieval using FLD-based methods at canopy level","volume":"48","author":"Liu","year":"2015","journal-title":"Eur. J. Remote Sens."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"3651","DOI":"10.3390\/rs70403651","article-title":"An algorithm for Gross Primary Production (GPP) and Net Ecosystem Production (NEP) estimations in the midstream of the Heihe river Basin, China","volume":"7","author":"Wang","year":"2015","journal-title":"Remote Sens."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1754","DOI":"10.1111\/j.1365-2486.2005.001010.x","article-title":"Does the temperature sensitivity of decomposition of soil organic matter depend upon water content, soil horizon, or incubation time?","volume":"11","author":"Reichstein","year":"2005","journal-title":"Glob. Chang. Biol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/S0168-1923(00)00225-2","article-title":"Gap filling strategies for defensible annual sums of net ecosystem exchange","volume":"107","author":"Falge","year":"2001","journal-title":"Agric. For. Meteorol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1016\/j.rse.2004.02.012","article-title":"A new instrument for passive remote sensing 1. Measurements of sunlight-induced chlorophyll fluorescence","volume":"91","author":"Moya","year":"2004","journal-title":"Remote Sens. Environ."},{"key":"ref_53","unstructured":"Fournier, A., Goulas, Y., Daumard, F., Ounis, A., Champagne, S., and Moya, I. (2014, January 22\u201324). Effects of vegetation directional reflectance on sun-induced fluorescence retrieval in the oxygen absorption bands. Proceedings of the 5th International Workshop on Remote Sensing of Vegetation Fluorescence, Paris, France."},{"key":"ref_54","unstructured":"Miller, J.R., Berger, M., Goulas, Y., Jacquemoud, S., Louis, J., Moise, N., Mohammed, G., Moreno, J., Moya, I., and Pedr\u00f3s, R. (2005). 16365\/02\/NL\/FF, Final Report, ESA Scientific and Technical Publications Branch, ESTEC."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1782","DOI":"10.1080\/01431161.2017.1404165","article-title":"Influence of the canopy BRDF characteristics and illumination conditions on the retrieval of solar-induced chlorophyll fluorescence","volume":"39","author":"Liu","year":"2017","journal-title":"Int. J. Remote Sens."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"026","DOI":"10.1117\/1.JRS.11.026032","article-title":"Improving the retrieval of solar-induced chlorophyll fluorescence at canopy level by modeling the relative peak height of the apparent reflectance","volume":"11","author":"Hu","year":"2017","journal-title":"J. Appl. Remote Sens."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"7954","DOI":"10.3390\/s110807954","article-title":"Ground-based optical measurements at European flux sites: A review of methods, instruments and current controversies","volume":"11","author":"Balzarolo","year":"2011","journal-title":"Sensors"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.rse.2013.01.017","article-title":"Using field spectroscopy to assess the potential of statistical approaches for the retrieval of sun-induced chlorophyll fluorescence from ground and space","volume":"133","author":"Guanter","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_59","doi-asserted-by":"crossref","unstructured":"Wang, S., Zhang, L., Huang, C., and Qiao, N. (2017, January 23\u201328). Ground-based long-term remote sensing of solar-induced chlorophyll fluorescence: Methods, challenges and opportunities. Proceedings of the 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, TX, USA.","DOI":"10.1109\/IGARSS.2017.8127845"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"4065","DOI":"10.1093\/jxb\/eru191","article-title":"Linking chlorophyll a fluorescence to photosynthesis for remote sensing applications: Mechanisms and challenges","volume":"65","author":"Atherton","year":"2014","journal-title":"J. Exp. Bot."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1562\/0031-8655(2000)072<0075:TEODTU>2.0.CO;2","article-title":"The effect of decreasing temperature up to chilling values on the in vivo F685\/F735 chlorophyll fluorescence ratio in Phaseolus vulgaris and Pisum sativum: The role of the photosystem I contribution to the 735 nm fluorescence band","volume":"72","author":"Agati","year":"2000","journal-title":"Photochem. Photobiol."},{"key":"ref_62","first-page":"1","article-title":"New methods for retrieval of chlorophyll red fluorescence from hyper-spectral satellite instruments: Simulations and application to GOME-2 and SCIAMACHY","volume":"9","author":"Joiner","year":"2016","journal-title":"Atmos. Meas. Tech. Discuss."},{"key":"ref_63","doi-asserted-by":"crossref","unstructured":"Liu, X., Guanter, L., Liu, L., Damm, A., Malenovsk\u00fd, Z., Rascher, U., Peng, D., Du, S., and Gastellu-Etchegorry, J.-P. (2018). Downscaling of solar-induced chlorophyll fluorescence from canopy level to photosystem level using a random forest model. Remote Sens. Environ., in press.","DOI":"10.1016\/j.rse.2018.05.035"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/13\/3009\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:03:36Z","timestamp":1760187816000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/13\/3009"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,7,8]]},"references-count":63,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2019,7]]}},"alternative-id":["s19133009"],"URL":"https:\/\/doi.org\/10.3390\/s19133009","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,7,8]]}}}