{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T10:56:58Z","timestamp":1790679418981,"version":"4.1.0"},"reference-count":77,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2019,3,6]],"date-time":"2019-03-06T00:00:00Z","timestamp":1551830400000},"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>A synergic integration of Synthetic Aperture Radar (SAR) and optical time series offers an unprecedented opportunity in vegetation phenology monitoring for mountain agriculture management. In this paper, we performed a correlation analysis of radar signal to vegetation and soil conditions by using a time series of Sentinel-1 C-band dual-polarized (VV and VH) SAR images acquired in the South Tyrol region (Italy) from October 2014 to September 2016. Together with Sentinel-1 images, we exploited corresponding Sentinel-2 images and ground measurements. Results show that Sentinel-1 cross-polarized VH backscattering coefficients have a strong vegetation contribution and are well correlated with the Normalized Difference Vegetation Index (NDVI) values retrieved from optical sensors, thus allowing the extraction of meadow phenological phases. Particularly for the Start Of Season (SOS) at low altitudes, the mean difference in days between Sentinel-1 and ground sensors is compatible with the acquisition time of the SAR sensor. However, the results show a decrease in accuracy with increasing altitude. The same trend is observed for senescence. The main outcomes of our investigations in terms of inter-satellite comparison show that Sentinel-1 is less effective than Sentinel-2 in detecting the SOS. At the same time, Sentinel-1 is as robust as Sentinel-2 in defining mowing events. Our study shows that SAR-Optical data integration is a promising approach for phenology detection in mountain regions.<\/jats:p>","DOI":"10.3390\/rs11050542","type":"journal-article","created":{"date-parts":[[2019,3,7]],"date-time":"2019-03-07T10:52:22Z","timestamp":1551955942000},"page":"542","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":88,"title":["Exploiting Time Series of Sentinel-1 and Sentinel-2 Imagery to Detect Meadow Phenology in Mountain Regions"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9802-8962","authenticated-orcid":false,"given":"Laura","family":"Stendardi","sequence":"first","affiliation":[{"name":"Faculty of Science and Technology, Free University of Bozen-Bolzano, 39100 Bolzano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stein Rune","family":"Karlsen","sequence":"additional","affiliation":[{"name":"NORCE Norwegian Research Centre AS, Measurement Science, P.O. Box 6434, N-9294 Troms\u00f8, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georg","family":"Niedrist","sequence":"additional","affiliation":[{"name":"EuracResearch, Institute for Alpine Environment, 39100 Bolzano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1887-3788","authenticated-orcid":false,"given":"Renato","family":"Gerdol","sequence":"additional","affiliation":[{"name":"Department of Life Sciences and Biotechnology, University of Ferrara, I-44121 Ferrara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc","family":"Zebisch","sequence":"additional","affiliation":[{"name":"EuracResearch, Institute for Earth Observation, 39100 Bolzano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mattia","family":"Rossi","sequence":"additional","affiliation":[{"name":"EuracResearch, Institute for Earth Observation, 39100 Bolzano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1968-0125","authenticated-orcid":false,"given":"Claudia","family":"Notarnicola","sequence":"additional","affiliation":[{"name":"EuracResearch, Institute for Earth Observation, 39100 Bolzano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1006\/jema.1999.0335","article-title":"Agricultural abandonment in mountain areas of Europe: environmental consequences and policy response","volume":"59","author":"MacDonald","year":"2000","journal-title":"J. Environ. Manag."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Mann, S. (2013). Future of mountain agriculture in the Alps. The Future of Mountain Agriculture, Springer.","DOI":"10.1007\/978-3-642-33584-6"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Lieth, H. (1974). Purposes of a Phenology Book. Phenology and Seasonality Modeling, Springer.","DOI":"10.1007\/978-3-642-51863-8"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/S0168-1923(03)00161-8","article-title":"Climate changes and trends in phenology of fruit trees and field crops in Germany, 1961\u20132000","volume":"121","author":"Chmielewski","year":"2004","journal-title":"Agric. For. Meteorol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1111\/j.1654-109X.2002.tb00547.x","article-title":"Impact of land use changes on mountain vegetation","volume":"5","author":"Tasser","year":"2002","journal-title":"Appl. Veg. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1023\/A:1024458411589","article-title":"Climatic change in mountain regions: A review of possible impacts","volume":"59","author":"Beniston","year":"2003","journal-title":"Clim. Chang."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1023\/A:1010632015572","article-title":"Potential impact of climate change on vegetation in the European Alps: A review","volume":"50","author":"Theurillat","year":"2001","journal-title":"Clim. Chang."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1117\/12.966243","article-title":"Remote sensing of vegetation characteristics for farm management","volume":"475","author":"Jackson","year":"1984","journal-title":"Remote Sens. Crit. Rev. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1071","DOI":"10.1109\/PROC.1985.13238","article-title":"Spectral inputs to crop identification and condition assessment","volume":"73","author":"Bauer","year":"1985","journal-title":"Proc. IEEE"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/S0034-4257(97)00045-X","article-title":"Opportunities and limitations for image-based remote sensing in precision crop management","volume":"61","author":"Moran","year":"1997","journal-title":"Remote Sens. Environ."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"647","DOI":"10.14358\/PERS.69.6.647","article-title":"Remote sensing for crop management","volume":"69","author":"Pinter","year":"2003","journal-title":"Photogramm. Eng. Remote Sens."},{"key":"ref_12","unstructured":"Rouse, J.W., Haas, R.H., Schell, J.A., and Deering, D.W. (1974). Monitoring Vegetation Systems in the Great Plains with ERTS, NASA."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2269","DOI":"10.1080\/01431169008955174","article-title":"phenological classification of terrestrial vegetation cover using shortwave vegetation index imagery","volume":"11","author":"Lloyd","year":"1990","journal-title":"Int. J. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"703","DOI":"10.2307\/3235884","article-title":"Measuring phenological variability from satellite imagery","volume":"5","author":"Reed","year":"1994","journal-title":"J. Veg. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1029\/97GB00330","article-title":"A continental phenology model for monitoring vegetation responses to interannual climatic variability","volume":"11","author":"White","year":"1997","journal-title":"Glob. Biogeochem. Cycles"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1016\/j.cageo.2004.05.006","article-title":"TIMESAT\u2014A program for analyzing time-series of satellite sensor data","volume":"30","author":"Eklundh","year":"2004","journal-title":"Comput. Geosci."},{"key":"ref_17","first-page":"109","article-title":"Mapping crop key phenological stages in the North China Plain using NOAA time series images","volume":"4","author":"Xin","year":"2002","journal-title":"Int. J. Appl. Earth Obs. Geoinform."},{"key":"ref_18","first-page":"188","article-title":"Mapping crop phenology using NDVI time-series derived from HJ-1 A\/B data","volume":"34","author":"Pan","year":"2015","journal-title":"Int. J. Appl. Earth Obs. Geoinform."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1016\/0034-4257(94)00073-V","article-title":"Optical remote sensing of vegetation: Modeling, caveats, and algorithms","volume":"51","author":"Myneni","year":"1995","journal-title":"Remote Sens. Environ."},{"key":"ref_20","unstructured":"Richards, M.A. (2005). Introduction to Radar Systems. Fundamentals of Radar Signal Processing, Tata McGraw-Hill Education."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1109\/TAP.1975.1140999","article-title":"Radar response to vegetation","volume":"23","author":"Ulaby","year":"1975","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1029\/RS013i002p00357","article-title":"Vegetation modeled as a water cloud","volume":"13","author":"Attema","year":"1978","journal-title":"Radio Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1092","DOI":"10.1109\/36.406698","article-title":"Monitoring of rice crop growth from space using the ERS-1 C-band SAR","volume":"33","author":"Kurosu","year":"1995","journal-title":"IEEE Trans. Geosci. Remote Sens"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Choudhury, I., Chakraborty, M., and Parihar, J.S. (2007, January 23\u201327). Estimation of rice growth parameter and crop phenology with conjunctive use of RADARSAT and ENVISAT. Proceedings of the ENVISAT Symposium, Montreux, Switzerland.","DOI":"10.1080\/01431160500239172"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Lopez-Sanchez, J.M., Vicente-Guijalba, F., Ballester-Berman, J.D., and Cloude, S.R. (2015, January 26\u201331). Retrieving rice phenology with X-band co-polar data: A multi-incidence multi-year experiment. Proceedings of the 2015 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Milan, Italy.","DOI":"10.1109\/IGARSS.2015.7326696"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2695","DOI":"10.1109\/TGRS.2011.2176740","article-title":"David Rice phenology monitoring by means of SAR polarimetry at X-band","volume":"50","author":"Cloude","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_27","first-page":"2695","article-title":"Polarimetric response of rice fields at C-band: Analysis and phenology retrieval","volume":"52","author":"Cloude","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1081","DOI":"10.1109\/LGRS.2013.2286214","article-title":"Crop phenology estimation using a multitemporal model and a Kalman filtering strategy","volume":"11","year":"2014","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1300","DOI":"10.1002\/2014RS005498","article-title":"Rice growth monitoring using simulated compact polarimetric C band SAR","volume":"49","author":"Yang","year":"2014","journal-title":"Radio Sci."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Shang, J., Jiao, X., McNairn, H., Kovacs, J., Walters, D., Ma, B., and Geng, X. (2013, January 12\u201316). Tracking crop phenological development of spring wheat using Synthetic Aperture Radar (SAR) in northern Ontario, Canada. Proceedings of the 2013 Second International Conference onAgro-Geoinformatics (Agro-Geoinformatics), Fairfax, VA, USA.","DOI":"10.1109\/Argo-Geoinformatics.2013.6621975"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2509","DOI":"10.1109\/JSTARS.2016.2547843","article-title":"Paddy-rice phenology classification based on machine-learning methods using multitemporal co-polar X-band SAR images","volume":"9","author":"Erten","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"900","DOI":"10.1109\/TGRS.2014.2330377","article-title":"Paddy-rice monitoring using TanDEM-X","volume":"53","author":"Rossi","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"3512","DOI":"10.1109\/JSTARS.2016.2539498","article-title":"Contribution to real-time estimation of crop phenological states in a dynamical framework based on NDVI time series: Data fusion with SAR and temperature","volume":"9","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Tamm, T., Alite, K., Voormansik, K., and Talgre, L. (2016). Relating Sentinel-1 interferometric coherence to mowing events on grasslands. Remote Sens., 8.","DOI":"10.3390\/rs8100802"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"8081","DOI":"10.1080\/01431161.2013.829593","article-title":"Towards a detection of grassland cutting practices with dual polarimetric TerraSAR-X data","volume":"34","author":"Voormansik","year":"2013","journal-title":"Int. J. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"3773","DOI":"10.1109\/JSTARS.2014.2308273","article-title":"Characteristics analysis and classification of crop harvest patterns by exploiting high-frequency multipolarization SAR data","volume":"7","author":"Zhao","year":"2014","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_37","first-page":"1","article-title":"Potentials of polarimetric SAR interferometry for agriculture monitoring","volume":"44","year":"2009","journal-title":"Radio Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"525","DOI":"10.5589\/m03-069","article-title":"The application of C-band polarimetric SAR for agriculture: A review","volume":"30","author":"McNairn","year":"2004","journal-title":"Can. J. Remote Sens."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"6163","DOI":"10.3390\/rs6076163","article-title":"Combined use of multi-temporal optical and radar satellite images for grassland monitoring","volume":"7","author":"Dusseux","year":"2014","journal-title":"Remote Sens."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1016\/j.rse.2009.04.005","article-title":"Potential of SAR sensors TerraSAR-X, ASAR\/ENVISAT and PALSAR\/ALOS for monitoring sugarcane crops on Reunion Island","volume":"113","author":"Baghdadi","year":"2009","journal-title":"Remote Sens. Environ."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"246","DOI":"10.5589\/m02-020","article-title":"summary of experimental results to assess the contribution of SAR for mapping vegetation biomass and soil moisture","volume":"28","author":"Paloscia","year":"2002","journal-title":"Can. J. Remote Sens."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1109\/JSTARS.2010.2052916","article-title":"Dense temporal series of C-and L-band SAR data for soil moisture retrieval over agricultural crops","volume":"4","author":"Balenzano","year":"2011","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.rse.2011.05.028","article-title":"GMES Sentinel-1 mission","volume":"120","author":"Torres","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.rse.2011.11.026","article-title":"Sentinel-2: ESA\u2019s optical high-resolution mission for GMES operational services","volume":"120","author":"Drusch","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_45","unstructured":"(2018, September 09). Istituto Provinciale di Statistica, Bolzano (ASTAT) 6\u00b0 Censimento Generale Dell\u2019Agricoltura. Available online: http:\/\/astat.provincia.bz.it\/downloads\/JB2017_K2.pdf."},{"key":"ref_46","first-page":"35","article-title":"Mapping Ecosystem Services supply in mountain regions: A case study from South Tyrol (Italy)","volume":"4","author":"Schirpke","year":"2014","journal-title":"Ann. Bot."},{"key":"ref_47","unstructured":"Meadows, P., and Hajduch, G. (2018, November 12). S-1A & S-1B Annual Performance Report for 2016. Available online: https:\/\/sentinel.esa.int\/documents\/247904\/2370914\/Sentinel-1-Annual-Performance-Report-2016."},{"key":"ref_48","unstructured":"(2018, November 27). Spectral Reflectance Sensor, Operator\u2019s Manual. Available online: http:\/\/manuals.decagon.com\/Manuals\/14597_SRS_Web.pdf."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"4305","DOI":"10.5194\/bg-11-4305-2014","article-title":"Evaluating remote sensing of deciduous forest phenology at multiple spatial scales using PhenoCam imagery","volume":"16","author":"Klosterman","year":"2014","journal-title":"Biogeosciences"},{"key":"ref_50","unstructured":"Adrian, T., and Kurt, H. (2019, January 11). Tseries: Time Series Analysis and Computational Finance Note = R Package Version 0.10-46. Available online: https:\/\/CRAN.R-project.org\/package=tseries."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"596","DOI":"10.1109\/TGRS.2003.821065","article-title":"Quantitative retrieval of soil moisture content and surface roughness from multipolarized radar observations of bare soil surfaces","volume":"42","author":"Oh","year":"2004","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"542","DOI":"10.1037\/0033-2909.114.3.542","article-title":"Dominance analysis: A new approach to the problem of relative importance of predictors in multiple regression","volume":"114","author":"Budescu","year":"1993","journal-title":"Psychol. Bull."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1585","DOI":"10.1080\/01431169208904212","article-title":"The Best Index Slope Extraction (BISE): A method for reducing noise in NDVI time-series","volume":"13","author":"Viovy","year":"1992","journal-title":"Int. J. Remote Sens."},{"key":"ref_54","unstructured":"(2018, September 13). Maximilian Lange and Daniel Doktor Phenex: Auxiliary Functions for Phenological Data Analysis. Available online: https:\/\/CRAN.R-project.org\/package=phenex."},{"key":"ref_55","unstructured":"Hogda, K.A., Karlsen, S.R., and Solheim, I. (2001, January 9\u201313). Climatic change impact on growing season in Fennoscandia studied by a time series of NOAA AVHRR NDVI data. Proceedings of the IEEE 2001 International Geoscience and Remote Sensing Symposium (IGARSS\u201901), Sydney, Australia."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"416","DOI":"10.1111\/j.1466-822X.2006.00234.x","article-title":"Satellite-based mapping of the growing season and bioclimatic zones in Fennoscandia","volume":"3","author":"Karlsen","year":"2006","journal-title":"Glob. Ecol. Biogeogr."},{"key":"ref_57","unstructured":"Cleveland, W.S., Grosse, E., and Shyu, W.M. (1992). Local regression models. Statistical Models in S. Wadsworth & Brooks\/Cole Advanced Books & Software Pacific Grove, CA, CRC Press."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/S0034-4257(01)00343-1","article-title":"Season-long daily measurements of multifrequency (Ka, Ku, X, C, and L) and full-polarization backscatter signatures over paddy rice field and their relationship with biological variables","volume":"81","author":"Inoue","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1016\/j.rse.2013.09.001","article-title":"Capability of C-band backscattering coefficients from high-resolution satellite SAR sensors to assess biophysical variables in paddy rice","volume":"140","author":"Inoue","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/S0034-4257(96)00243-X","article-title":"Combining multifrequency microwave and optical data for crop management","volume":"61","author":"Moran","year":"1997","journal-title":"Remote Sens. Environ."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"873","DOI":"10.1109\/36.917914","article-title":"The relationship between the backscattering coefficient and the biomass of narrow and broad leaf crops","volume":"39","author":"Macelloni","year":"2001","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"2265","DOI":"10.1109\/JSTARS.2013.2241735","article-title":"First results of monitoring nature conservation sites in alpine region by using very high resolution (VHR) X-band SAR data","volume":"6","author":"Ali","year":"2013","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"1057","DOI":"10.1109\/TGRS.2011.2166080","article-title":"A RADARSAT-2 quad-polarized time series for monitoring crop and soil conditions in Barrax, Spain","volume":"50","author":"Moran","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.rse.2009.08.014","article-title":"Detecting trend and seasonal changes in satellite image time series","volume":"114","author":"Verbesselt","year":"2010","journal-title":"Remote Sens. Environ."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1016\/0034-4257(93)90053-Z","article-title":"Estimating surface soil moisture and leaf area index of a wheat canopy using a dual-frequency (C and X bands) scatterometer","volume":"46","author":"Prevot","year":"1993","journal-title":"Remote Sens. Environ."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Baghdadi, N., El Hajj, M., Zribi, M., and Bousbih, S. (2017). Calibration of the water cloud model at C-Band for winter crop fields and grasslands. Remote Sens., 9.","DOI":"10.3390\/rs9090969"},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1016\/j.rse.2016.01.027","article-title":"Soil moisture retrieval over irrigated grassland using X-band SAR data","volume":"176","author":"Baghdadi","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_68","doi-asserted-by":"crossref","unstructured":"Notarnicola, C., and Solorza, R. (2014). Integration of remotely sensed images and electromagnetic models into a bayesian approach for soil moisture content retrieval: Methodology and effect of prior information. Dynamic Programming and Bayesian Inference, Concepts and Applications, InTech.","DOI":"10.5772\/57562"},{"key":"ref_69","first-page":"139","article-title":"Inferring the effect of plant and soil variables on C-and L-band SAR backscatter over agricultural fields, based on model analysis","volume":"30","author":"Inoue","year":"2007","journal-title":"Adv. Space Res."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.rse.2005.10.021","article-title":"Improved monitoring of vegetation dynamics at very high latitudes: A new method using MODIS NDVI","volume":"100","author":"Beck","year":"2006","journal-title":"Remote Sens. Environ."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1016\/j.rse.2004.03.014","article-title":"A simple method for reconstructing a high-quality NDVI time-series data set based on the Savitzky\u2013Golay filter","volume":"91","author":"Chen","year":"2004","journal-title":"Remote Sens. Environ."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"2253","DOI":"10.1002\/2015GL063586","article-title":"Intercomparison of satellite sensor land surface phenology and ground phenology in Europe","volume":"42","author":"Dash","year":"2015","journal-title":"Geophys. Res. Lett."},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Kosmala, M., Crall, A., Cheng, R., Hufkens, K., Henderson, S., and Richardson, A.D. (2016). Season Spotter: Using citizen science to validate and scale plant phenology from near-surface remote sensing. Remote Sens., 8.","DOI":"10.3390\/rs8090726"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"5679","DOI":"10.1038\/s41598-018-23804-6","article-title":"Intercomparison of phenological transition dates derived from the PhenoCam Dataset V1. 0 and MODIS satellite remote sensing","volume":"8","author":"Richardson","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_75","first-page":"433","article-title":"Plant communities of mountain grasslands in a broad cross-section of the Eastern Alps","volume":"206","author":"Tasser","year":"2011","journal-title":"Flora-Morphol. Distrib. Funct. Ecol. Plants"},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"1052","DOI":"10.1007\/s11430-012-4444-x","article-title":"Progresses on microwave remote sensing of land surface parameters","volume":"55","author":"Shi","year":"2012","journal-title":"Sci. China Earth Sci."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/S0034-4257(70)80021-9","article-title":"Physical and physiological basis for the reflectance of visible and near-infrared radiation from vegetation","volume":"1","author":"Knipling","year":"1970","journal-title":"Remote Sens. Environ."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/5\/542\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T12:36:42Z","timestamp":1760186202000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/5\/542"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,3,6]]},"references-count":77,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2019,3]]}},"alternative-id":["rs11050542"],"URL":"https:\/\/doi.org\/10.3390\/rs11050542","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,3,6]]}}}