{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T20:32:10Z","timestamp":1781901130783,"version":"3.54.5"},"reference-count":94,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,2,4]],"date-time":"2017-02-04T00:00:00Z","timestamp":1486166400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The availability of new fAPAR satellite products requires simultaneous efforts in validation to provide users with a better comprehension of product performance and evaluation of uncertainties. This study aimed to validate three fAPAR satellite products, GEOV1, MODIS C5, and MODIS C6, against ground references to determine to what extent the GCOS requirements on accuracy (maximum 10% or 5%) can be met in a deciduous beech forest site in a gently and variably sloped mountain site. Three ground reference fAPAR, differing for temporal (continuous or campaign mode) and spatial sampling (single points or Elementary Sampling Units\u2014ESUs), were collected using different devices: (1) Apogee (defined as benchmark in this study); (2) PASTIS; and (3) Digital cameras for collecting hemispherical photographs (DHP). A bottom-up approach for the upscaling process was used in the present study. Radiometric values of decametric images (Landsat-8) were extracted over the ESUs and used to develop empirical transfer functions for upscaling the ground measurements. The resulting high-resolution ground-based maps were aggregated to the spatial resolution of the satellite product to be validated considering the equivalent point spread function of the satellite sensors, and a correlation analysis was performed to accomplish the accuracy assessment. PASTIS sensors showed good performance as fAPARPASTIS appropriately followed the seasonal trends depicted by fAPARAPOGEE (benchmark) (R2 = 0.84; RMSE = 0.01). Despite small dissimilarities, mainly attributed to different sampling schemes and errors in DHP classification process, the agreement between fAPARPASTIS and fAPARDHP was noticeable considering all the differences between both approaches. The temporal courses of the three satellite products were found to be consistent with both Apogee and PASTIS, except at the end of the summer season when ground data were more affected by senescent leaves, with both MODIS C5 and C6 displaying larger short-term variability due to their shorter temporal composite period. MODIS C5 and C6 retrievals were obtained with the backup algorithm in most cases. The three green fAPAR satellite products under study showed good agreement with ground-based maps of canopy fAPAR at 10 h, with RMSE values lower than 0.06, very low systematic differences, and more than 85% of the pixels within GCOS requirements. Among them, GEOV1 fAPAR showed up to 98% of the points lying within the GCOS requirements, and slightly lower values (mean bias = \u22120.02) as compared with the ground canopy fAPAR, which is expected to be only slightly higher than green fAPAR in the peak season.<\/jats:p>","DOI":"10.3390\/rs9020126","type":"journal-article","created":{"date-parts":[[2017,2,6]],"date-time":"2017-02-06T11:29:27Z","timestamp":1486380567000},"page":"126","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Validation of PROBA-V GEOV1 and MODIS C5 &amp; C6 fAPAR Products in a Deciduous Beech Forest Site in Italy"],"prefix":"10.3390","volume":"9","author":[{"given":"Enrica","family":"Nestola","sequence":"first","affiliation":[{"name":"Institute of Agro-Environmental &amp; Forest Biology, National Research Council of Italy (CNR), Via Marconi 2, 05010 Porano (TR), Italy"},{"name":"Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), University of Tuscia, Via S. Camillo de Lellis snc, 01100 Viterbo, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jorge","family":"S\u00e1nchez-Zapero","sequence":"additional","affiliation":[{"name":"EOLAB, Parc Cient\u00edfic Universitat de Val\u00e8ncia, Catedr\u00e1tico August\u00edn Escardino 9, 46980 Paterna (Valencia), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Consuelo","family":"Latorre","sequence":"additional","affiliation":[{"name":"EOLAB, Parc Cient\u00edfic Universitat de Val\u00e8ncia, Catedr\u00e1tico August\u00edn Escardino 9, 46980 Paterna (Valencia), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Mazzenga","sequence":"additional","affiliation":[{"name":"Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), University of Tuscia, Via S. Camillo de Lellis snc, 01100 Viterbo, Italy"},{"name":"Institute of Agro-Environmental &amp; Forest Biology, National Research Council of Italy (CNR), Via Salaria km 29,300, 00016 Monterotondo Scalo (RM), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4790-9540","authenticated-orcid":false,"given":"Giorgio","family":"Matteucci","sequence":"additional","affiliation":[{"name":"Institute for Agricultural and Forestry Systems in the Mediterranean, National Research Council of Italy (CNR), Via Patacca 85, I-80056 Ercolano (NA), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Calfapietra","sequence":"additional","affiliation":[{"name":"Institute of Agro-Environmental &amp; Forest Biology, National Research Council of Italy (CNR), Via Marconi 2, 05010 Porano (TR), Italy"},{"name":"Global Change Research Institute, The Czech Academy of Sciences, B\u011blidla 4a, 603 00 Brno, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando","family":"Camacho","sequence":"additional","affiliation":[{"name":"EOLAB, Parc Cient\u00edfic Universitat de Val\u00e8ncia, Catedr\u00e1tico August\u00edn Escardino 9, 46980 Paterna (Valencia), Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1016\/j.tree.2005.05.011","article-title":"Using the satellite-derived NDVI to assess ecological responses to environmental change","volume":"20","author":"Pettorelli","year":"2005","journal-title":"Trends Ecol. Evol."},{"key":"ref_2","unstructured":"GTOS 52 (2008). Terrestrial Essential Climate Variables for Climate Change Assessment, Mitigation and Adaptation, Food and Agriculture Organization, United Nations."},{"key":"ref_3","unstructured":"Gobron, N., and Verstraete, M.M. (2009). ECV T10: Fraction of Absorbed Photosynthetically Active Radiation (FAPAR), Food and Agriculture Organization, United Nations."},{"key":"ref_4","unstructured":"Weiss, M., and Baret, F. (2011, January 10\u201315). fAPAR (fraction of Absorbed Photosynthetically Active Radiation) estimates at various scale. Proceedings of the 34th International Symposium for Remote Sensing of the Environment (ISRSE), Sydney, Australia."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1016\/j.rse.2007.03.001","article-title":"LAI and fAPAR CYCLOPES global products derived from VEGETATION. Part 2: Validation and comparison with MODIS collection 4 products","volume":"110","author":"Weiss","year":"2007","journal-title":"Remote Sens. Environ."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1890\/1051-0761(1998)008[1003:SDOAOP]2.0.CO;2","article-title":"Scale Dependence of Absorption of Photosynthetically Active Radiation in Terrestrial Ecosystems","volume":"8","author":"Asner","year":"1998","journal-title":"Ecol. Appl."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2196","DOI":"10.1016\/j.asr.2003.07.079","article-title":"Monitoring the photosynthetic activity of vegetation from remote sensing data","volume":"38","author":"Gobron","year":"2006","journal-title":"Adv. Space Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1093\/treephys\/19.10.673","article-title":"Seasonal variations in leaf area index, leaf chlorophyll, and water content; scaling-up to estimate fAPAR and carbon balance in a multilayer, multispecies temperate forest","volume":"19","author":"Gond","year":"1999","journal-title":"Tree Physiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2013","DOI":"10.1080\/01431160412331330293","article-title":"The state of vegetation in Europe following the 2003 drought","volume":"26","author":"Gobron","year":"2005","journal-title":"Int. J. Remote Sens."},{"key":"ref_10","first-page":"1","article-title":"Fraction of photosynthetically active radiation absorbed by Amazon tropical forest: A comparison of field measurements, modeling, and remote sensing","volume":"110","author":"Senna","year":"2005","journal-title":"J. Geophys. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"74","DOI":"10.1016\/0034-4257(94)00066-V","article-title":"Global net primary production: Combining ecology and remote sensing","volume":"51","author":"Field","year":"1995","journal-title":"Remote Sens. Environ."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2349","DOI":"10.1111\/j.1365-2486.2008.01647.x","article-title":"Diagnostic assessment of European gross primary production","volume":"14","author":"Jung","year":"2008","journal-title":"Glob. Chang. Biol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2547","DOI":"10.1016\/j.rse.2009.07.018","article-title":"Comparative analysis of MODIS-FAPAR and MERIS-MGVI datasets: Potential impacts on ecosystem modeling","volume":"113","author":"Seixas","year":"2009","journal-title":"Remote Sens. Environ."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1186\/1750-0680-4-8","article-title":"Satellite-based terrestrial production efficiency modeling","volume":"4","author":"McCallum","year":"2009","journal-title":"Carbon Balance Manag."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/S0034-4257(99)00056-5","article-title":"Direct and indirect estimation of leaf area index, fAPAR, and net primary production of terrestrial ecosystems","volume":"70","author":"Gower","year":"1999","journal-title":"Remote Sens. Environ."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/S0167-8809(02)00021-X","article-title":"Remote sensing of regional crop production in the Yaqui Valley, Mexico: Estimates and uncertainties","volume":"94","author":"Lobell","year":"2003","journal-title":"Agric. Ecosyst. Environ."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/0168-1923(94)02196-Q","article-title":"A method to estimate instantaneous and daily intercepted photosynthetically active radiation using a hemispherical sensor","volume":"74","author":"Hanan","year":"1995","journal-title":"Agric. For. Meteorol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1501","DOI":"10.1016\/j.agrformet.2010.07.011","article-title":"On the bias of instantaneous FAPAR estimates in open-canopy forests","volume":"150","author":"Widlowski","year":"2011","journal-title":"Agric. For. Meteorol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1016\/0034-4257(94)90016-7","article-title":"On the relationship between FAPAR and NDVI","volume":"49","author":"Myneni","year":"1994","journal-title":"Remote Sens. Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1641\/0006-3568(2004)054[0547:ACSMOG]2.0.CO;2","article-title":"A continuous satellite-derived measure of global terrestrial primary production","volume":"54","author":"Running","year":"2004","journal-title":"Bioscience"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"954","DOI":"10.1890\/04-0470","article-title":"Modelling gross primary production of an evergreen needleleaf forest using modis and climate data","volume":"15","author":"Xiao","year":"2005","journal-title":"Ecol. Appl."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2925","DOI":"10.1016\/j.rse.2010.07.012","article-title":"Comparison of multiple models for estimating gross primary production using MODIS and eddy covariance data in Harvard Forest","volume":"114","author":"Wu","year":"2010","journal-title":"Remote Sens. Environ."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1016\/S0034-4257(02)00074-3","article-title":"Global products of vegetation leaf area and fraction absorbed PAR from year one of MODIS data","volume":"83","author":"Myneni","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1016\/j.rse.2005.09.009","article-title":"Estimating light absorption by chlorophyll, leaf and canopy in a deciduous broadleaf forest using MODIS data and a radiative transfer model","volume":"99","author":"Zhang","year":"2005","journal-title":"Remote Sens. Environ."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"32257","DOI":"10.1029\/98JD02462","article-title":"Synergistic algorithm for estimating vegetation canopy leaf area index and fraction of absorbed photosynthetically active radiation from MODIS and MISR data","volume":"103","author":"Knyazikhin","year":"1998","journal-title":"J. Geophys. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2005JD006511","article-title":"Evaluation of fraction of absorbed photosynthetically active radiation products for different canopy radiation transfer regimes: Methodology and results using Joint Research Center products derived from SeaWiFS against ground-based estimations","volume":"111","author":"Gobron","year":"2006","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1007\/s11027-006-1012-8","article-title":"Establishing a earth observation product service for the terrestrial carbon community: The globcarbon initiative","volume":"11","author":"Plummer","year":"2006","journal-title":"Mitig. Adapt. Strateg. Glob. Chang."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2006JD008105","article-title":"Retrieving surface parameters for climate models from Moderate Resolution Imaging Spectroradiometer (MODIS)-Multiangle Imaging Spectroradiometer (MISR) albedo products","volume":"112","author":"Pinty","year":"2007","journal-title":"J. Geophys. Res. Atmos."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1016\/j.rse.2007.02.018","article-title":"LAI, fAPAR and fCover CYCLOPES global products derived from VEGETATION. Part 1: Principles of the algorithm","volume":"110","author":"Baret","year":"2007","journal-title":"Remote Sens. Environ."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2938","DOI":"10.1016\/j.rse.2008.02.008","article-title":"Deriving consistent long-term vegetation information from AVHRR reflectance data using a cover-triangle-based framework","volume":"112","author":"Donohue","year":"2008","journal-title":"Remote Sens. Environ."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1016\/j.rse.2012.12.027","article-title":"GEOV1: LAI and FAPAR essential climate variables and FCOVER global time series capitalizing over existing products. Part1: Principles of development and production","volume":"137","author":"Baret","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"310","DOI":"10.1016\/j.rse.2013.02.030","article-title":"GEOV1: LAI, FAPAR essential climate variables and FCOVER global time series capitalizing over existing products. Part 2: Validation and intercomparison with reference products","volume":"137","author":"Camacho","year":"2013","journal-title":"Remote Sens. Environ."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1885","DOI":"10.1109\/TGRS.2006.871215","article-title":"MODIS leaf area index products: From validation to algorithm improvement","volume":"44","author":"Yang","year":"2006","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_34","first-page":"463","article-title":"Intercomparison and quality assessment of MERIS, MODIS and SEVIRI FAPAR products over the Iberian Peninsula","volume":"21","author":"Camacho","year":"2013","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/j.rse.2013.08.037","article-title":"Evaluation of six satellite-derived Fraction of Absorbed Photosynthetic Active Radiation (FAPAR) products across the Australian continent","volume":"140","author":"Canadell","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"941","DOI":"10.1016\/j.rse.2009.12.009","article-title":"Comparison of four global FAPAR datasets over Northern Eurasia for the year 2000","volume":"114","author":"McCallum","year":"2010","journal-title":"Remote Sens. Environ."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Yan, K., Park, T., Yan, G., Chen, C., Yang, B., Liu, Z., Nemani, R., Knyazikhin, Y., and Myneni, R. (2016). Evaluation of MODIS LAI\/FPAR Product Collection 6. Part 1: Consistency and Improvements. Remote Sens., 8.","DOI":"10.3390\/rs8050359"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Yan, K., Park, T., Yan, G., Liu, Z., Yang, B., Chen, C., Nemani, R., Knyazikhin, Y., and Myneni, R. (2016). Evaluation of MODIS LAI\/FPAR Product Collection 6. Part 2: Validation and Intercomparison. Remote Sens., 8.","DOI":"10.3390\/rs8060460"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.rse.2013.12.005","article-title":"Intercomparison of fraction of absorbed photosynthetically active radiation products derived from satellite data over Europe","volume":"142","author":"Gonsamo","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1359","DOI":"10.3390\/rs70201359","article-title":"Validation of MODIS and GEOV1 fPAR products in a boreal forest site in Finland","volume":"7","author":"Majasalmi","year":"2015","journal-title":"Remote Sens."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/j.rse.2015.03.025","article-title":"Assessment of five global satellite products of fraction of absorbed photosynthetically active radiation: Intercomparison and direct validation against ground-based data","volume":"163","author":"Tao","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"4190","DOI":"10.3390\/rs6054190","article-title":"On line validation exercise (OLIVE): A web based service for the validation of medium resolution land products. application to FAPAR products","volume":"6","author":"Weiss","year":"2014","journal-title":"Remote Sens."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TGRS.2006.872529","article-title":"Validation of Global Moderate-Resolution LAI Products: A Framework Proposed Within the CEOS Land Product Validation Subgroup","volume":"44","author":"Morisette","year":"2006","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_44","unstructured":"The Global Climate Observing System (2011). Systematic Observation Requirements for Satellite-Based Data Products for Climate\u20142011 Update, The Global Climate Observing System."},{"key":"ref_45","unstructured":"GIO Global Land Component\u2014Lot I \u201cOperation of the Global Land Component\u201d, Framework Service Contract N\u00b0 388533 (JRC), Product User Manual, Fraction of Absorbed Photosynthetically Active Radiation (FAPAR)\u2014Version 1. Available online: http:\/\/land.copernicus.eu\/global\/sites\/default\/files\/products\/GIOGL1_ATBD_FAPARV1_I1.10.pdf."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1016\/j.rse.2004.09.008","article-title":"Quality assessment and improvement of temporally composited products of remotely sensed imagery by combination of VEGETATION 1 and 2 images","volume":"94","author":"Hagolle","year":"2005","journal-title":"Remote Sens. Environ."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"93","DOI":"10.5194\/isprsarchives-XL-7-W3-93-2015","article-title":"Early validation of PROBA-V GEOV1 LAI, FAPAR and FCOVER products for the continuity of the Copernicus Global Land Service","volume":"XL-7\/W3","author":"Camacho","year":"2015","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1109\/36.581987","article-title":"Second Simulation of the Satellite Signal in the Solar Spectrum, 6s: An Overview","volume":"35","author":"Vermote","year":"1997","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1843","DOI":"10.1109\/TGRS.2006.876026","article-title":"MODIS Land Cover and LAI Collection 4 Product Quality Across Nine Sites in the Western Hemisphere","volume":"44","author":"Cohen","year":"2006","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1818","DOI":"10.1109\/TGRS.2005.862266","article-title":"Validation of MODIS FPAR products in boreal forests of alaska","volume":"44","author":"Steinberg","year":"2006","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.rse.2006.12.004","article-title":"Comparison and validation of MODIS and VEGETATION global LAI products over four BigFoot sites in North America","volume":"109","author":"Pisek","year":"2007","journal-title":"Remote Sens. Environ."},{"key":"ref_52","first-page":"1","article-title":"Validation and intercomparison of global Leaf Area Index products derived from remote sensing data","volume":"113","author":"Garrigues","year":"2008","journal-title":"J. Geophys. Res."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"610","DOI":"10.1016\/j.rse.2012.06.013","article-title":"Theoretical uncertainty analysis of global MODIS, CYCLOPES, and GLOBCARBON LAI products using a triple collocation method","volume":"124","author":"Fang","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"340","DOI":"10.1007\/s00442-004-1588-1","article-title":"Comparisons of \u03b413 C of photosynthetic products and ecosystem respiratory CO2 and their responses to seasonal climate variability","volume":"140","author":"Scartazza","year":"2004","journal-title":"Oecologia"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1016\/S0065-2504(08)60018-5","article-title":"Estimates of the annual net carbon and water exchange of forests: The EUROFLUX methodology","volume":"30","author":"Aubinet","year":"2000","journal-title":"Adv. Ecol. Res."},{"key":"ref_56","unstructured":"Palahi, M., Byrot, Y., and Rois, M. (2007). Scientific Tools and Research Needs for Multifunctional Mediterranean Forest Ecosystem Management, European Forest Institute (EFI) Proceedings."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1111\/j.1475-2743.2010.00300.x","article-title":"Predicting changes in soil organic carbon in mediterranean and alpine forests during the Kyoto Protocol commitment periods using the CENTURY model","volume":"26","author":"Chiti","year":"2010","journal-title":"Soil Use Manag."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1060","DOI":"10.1093\/treephys\/tpw038","article-title":"Investigating the European beech (Fagus sylvatica L.) leaf characteristics along the vertical canopy profile: leaf structure, photosynthetic capacity, light energy dissipation and photoprotection mechanisms","volume":"36","author":"Scartazza","year":"2016","journal-title":"Tree Physiol."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"960","DOI":"10.1093\/treephys\/tpt065","article-title":"Effect of environmental variables and stand structure on ecosystem respiration components in a Mediterranean beech forest","volume":"33","author":"Guidolotti","year":"2013","journal-title":"Tree Physiol."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"730","DOI":"10.1093\/treephys\/tpt045","article-title":"Seasonal and inter-annual dynamics of growth, non-structural carbohydrates and C stable isotopes in a Mediterranean beech forest","volume":"33","author":"Scartazza","year":"2013","journal-title":"Tree Physiol."},{"key":"ref_61","unstructured":"Apogee Instruments Inc (2016). Owner\u2019s Manual. Apogee Instruments. Quantum sensor (Models SQ-110 and SQ-300 Series), Apogee Instruments Inc."},{"key":"ref_62","unstructured":"Sobrino, J.A. (2014). Fourth Recent Advances in Quantitative Remote Sensing, Publicacions de la Universitat de Val\u00e8ncia."},{"key":"ref_63","unstructured":"Weiss, M., and Baret, F. CAN-EYE User Manual. V6.313. Available online: https:\/\/www6.paca.inra.fr\/can-eye\/Documentation-Publications\/Documentation."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.agrformet.2003.08.001","article-title":"Review of methods for in situ leaf area index (LAI) determination","volume":"121","author":"Weiss","year":"2004","journal-title":"Agric. For. Meteorol."},{"key":"ref_65","unstructured":"Liang, S., Li, X., and Wang, J. (2012). Advanced Remote Sensing: Terrestrial Information Extraction and Applications, Elsevier Inc."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Wang, Y., Xie, D., Liu, S., Hu, R., Li, Y., and Yan, G. (2016). Scaling of FAPAR from the Field to the Satellite. Remote Sens., 8.","DOI":"10.3390\/rs8040310"},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"2254","DOI":"10.1109\/JSTARS.2013.2275176","article-title":"Variations of foliage chlorophyll fAPAR and foliage non-chlorophyll fAPAR (fAPARchl, fAPARnonchl) at the Harvard Forest","volume":"6","author":"Zhang","year":"2013","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.agrformet.2003.08.027","article-title":"Review of methods for in situ leaf area index determination Part I. Theories, sensors and hemispherical photography","volume":"121","author":"Jonckheere","year":"2004","journal-title":"Agric. For. Meteorol."},{"key":"ref_69","unstructured":"Varlet-Grancher, R.B.C., and Sinoquet, H. (1993). Crop Structure and Light Microclimate\u2014Characterization and Applications, INRA."},{"key":"ref_70","unstructured":"Weiss, M. CAN-EYE Output Variables. Definitions and Theoretical Background. Available online: https:\/\/www4.paca.inra.fr\/can-eye\/Documentation-Publications\/Documentation."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1016\/j.agrformet.2008.07.014","article-title":"Derivation of high-resolution leaf area index maps in support of validation activities: Application to the cropland Barrax site","volume":"149","year":"2009","journal-title":"Agric. For. Meteorol."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"28","DOI":"10.2307\/1942049","article-title":"Relationships Between NDVI, Canopy Structure, and Photosynthesis in Three Californian Vegetation Types","volume":"5","author":"Gamon","year":"1995","journal-title":"Ecol. Appl."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/0034-4257(92)90131-3","article-title":"Vegetation canopy PAR absorptance and the normalized difference vegetation index - An assessment using the SAIL model","volume":"39","author":"Goward","year":"1992","journal-title":"Remote Sens. Environ."},{"key":"ref_74","doi-asserted-by":"crossref","unstructured":"Nestola, E., Calfapietra, C., Emmerton, C., Wong, C., Thayer, D., and Gamon, J. (2016). Monitoring Grassland Seasonal Carbon Dynamics, by Integrating MODIS NDVI, Proximal Optical Sampling, and Eddy Covariance Measurements. Remote Sens., 8.","DOI":"10.3390\/rs8030260"},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"481","DOI":"10.1109\/TGRS.1995.8746029","article-title":"The interpretation of spectral vegetation indexes","volume":"33","author":"Myneni","year":"1995","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1016\/j.rse.2004.04.009","article-title":"Evaluation of MODIS LAI, fAPAR and the relation between fAPAR and NDVI in a semi-arid environment using in situ measurements","volume":"91","author":"Fensholt","year":"2004","journal-title":"Remote Sens. Environ."},{"key":"ref_77","unstructured":"Rouse, J.W., Haas, R.H., Schell, J.A., and Deering, D.W. (1974). Third Earth Resources Technology Satellite-1 Symposium, NASA."},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"1017","DOI":"10.1080\/01621459.1997.10474057","article-title":"Robust linear model selection by cross-validation","volume":"92","author":"Ronchetti","year":"1997","journal-title":"J. Am. Stat. Assoc."},{"key":"ref_79","unstructured":"Latorre, C. Vegetation Field Data and Production of Ground-Based Maps: \u201cCollelongo Site\u2014Selvapiana, Italy\u201d 8th July and 25th September, 2015. Available online: http:\/\/fp7-imagines.eu\/media\/Documents\/ImagineS_RP7.5_FieldCampaign_Collelongo2015_I1.00.pdf."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1016\/j.rse.2015.09.021","article-title":"The MODIS (collection V006) BRDF\/albedo product MCD43D: Temporal course evaluated over agricultural landscape","volume":"170","author":"Mira","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_81","unstructured":"Schowengerdt, R.A. (2007). Remote Sensing: Models and Methods for Image Processing, Academic Press. [3rd ed.]."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"2686","DOI":"10.1016\/j.rse.2011.05.026","article-title":"Crop specific green area index retrieval from MODIS data at regional scale by controlling pixel-target adequacy","volume":"115","author":"Duveiller","year":"2011","journal-title":"Remote Sens. Environ."},{"key":"ref_83","unstructured":"Schaepman-Strub, G., Rom\u00e1n, M., and Nickeson, J. (2014). Best Practice for Satellite-Derived Land Product Validation. Land Product Validation Subgroup (WGCV\/CEOS), Committee on Earth Observation Satellites (CEOS)."},{"key":"ref_84","unstructured":"Makar, K., De Sousa, B., and Gould, R. (2014). Sustainability in Statistics Education. Proceedings of the Ninth International Conference on Teaching Statistics (ICOTS9), Flagstaff, AZ, USA, 13\u201318 July 2014, International Statistical Instutute."},{"key":"ref_85","unstructured":"Sobrino, J. (2014). Fourth Recent Advances in Quantitative Remote Sensing, Publicacions de la Universitat de Val\u00e8ncia."},{"key":"ref_86","unstructured":"Sobrino, J.A. (2014). Fourth Recent Advances in Quantitative Remote Sensing, Publicacions de la Universitat de Val\u00e8ncia."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"1193","DOI":"10.1016\/j.agrformet.2008.02.014","article-title":"Intercomparison and sensitivity analysis of Leaf Area Index retrievals from LAI-2000, AccuPAR, and digital hemispherical photography over croplands","volume":"148","author":"Garrigues","year":"2008","journal-title":"Agric. For. Meteorol."},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.foreco.2012.07.023","article-title":"Effects of reproduction methods and overstory species composition on understory light availability in longleaf pine-slash pine ecosystems","volume":"284","author":"Sharma","year":"2012","journal-title":"For. Ecol. Manag."},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"2534","DOI":"10.1080\/01431161.2014.883096","article-title":"SPOT-VEGETATION GEOV1 biophysical parameters in semi-arid agro-ecosystems","volume":"35","author":"Raymaekers","year":"2014","journal-title":"Int. J. Remote Sens."},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.agrformet.2014.08.006","article-title":"Estimation of LAI, fAPAR and fCover of Sahel rangelands (Gourma, Mali)","volume":"198","author":"Mougin","year":"2014","journal-title":"Agric. For. Meteorol."},{"key":"ref_91","first-page":"1","article-title":"Multitemporal monitoring of plant area index in the valencia rice district with PocketLAI","volume":"8","author":"Confalonieri","year":"2016","journal-title":"Remote Sens."},{"key":"ref_92","first-page":"77","article-title":"Biodiversity in European beech forests\u2014A review with recommendations for sustainable forest management","volume":"53","author":"Brunet","year":"2010","journal-title":"Ecol. Bull."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1016\/S0034-4257(02)00173-6","article-title":"An improved strategy for regression of biophysical variables and Landsat ETM+ data","volume":"84","author":"Cohen","year":"2003","journal-title":"Remote Sens. Environ."},{"key":"ref_94","unstructured":"Knyazikhin, Y., Glassy, J., Privette, J.L., Tian, Y., Lotsch, A., Zhang, Y., Wang, Y., Morisette, J.T., Votava, P., and Myneni, R.B. MODIS Leaf Area Index (LAI) And Fraction Of Photosynthetically Active Radiation Absorbed By Vegetation (FPAR) Product, Available online: https:\/\/modis.gsfc.nasa.gov\/data\/atbd\/atbd_mod15.pdf."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/2\/126\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:27:26Z","timestamp":1760207246000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/2\/126"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,2,4]]},"references-count":94,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2017,2]]}},"alternative-id":["rs9020126"],"URL":"https:\/\/doi.org\/10.3390\/rs9020126","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,2,4]]}}}