{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T23:51:21Z","timestamp":1783122681701,"version":"3.54.6"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2014,11,6]],"date-time":"2014-11-06T00:00:00Z","timestamp":1415232000000},"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>Rice is the most important food security crop in Asia. Information on its seasonal extent forms part of the national accounting of many Asian countries. Synthetic Aperture Radar (SAR) imagery is highly suitable for detecting lowland rice, especially in tropical and subtropical regions, where pervasive cloud cover in the rainy seasons precludes the use of optical imagery. Here, we present a simple, robust, rule-based classification for mapping rice area with regularly acquired, multi-temporal, X-band, HH-polarized SAR imagery and site-specific parameters for classification. The rules for rice detection are based on the well-studied temporal signature of rice from SAR backscatter and its relationship with crop stages. We also present a procedure for estimating the parameters based on \u201ctemporal feature descriptors\u201d that concisely characterize the key information in the rice signatures in monitored field locations within each site. We demonstrate the robustness of the approach on a very large dataset. A total of 127 images across 13 footprints in six countries in Asia were obtained between October 2012, and April 2014, covering 4.78 m ha. More than 1900 in-season site visits were conducted across 228 monitoring locations in the footprints for classification purposes, and more than 1300 field observations were made for accuracy assessment. Some 1.6 m ha of rice were mapped with classification accuracies from 85% to 95% based on the parameters that were closely related to the observed temporal feature descriptors derived for each site. The 13 sites capture much of the diversity in water management, crop establishment and maturity in South and Southeast Asia. The study demonstrates the feasibility of rice detection at the national scale using multi-temporal SAR imagery with robust classification methods and parameters that are based on the knowledge of the temporal dynamics of the rice crop. We highlight the need for the development of an open-access library of temporal signatures, further investigation into temporal feature descriptors and better ancillary data to reduce the risk of misclassification with surfaces that have temporal backscatter dynamics similar to those of rice. We conclude with observations on the need to define appropriate SAR acquisition plans to support policies and decisions related to food security.<\/jats:p>","DOI":"10.3390\/rs61110773","type":"journal-article","created":{"date-parts":[[2014,11,7]],"date-time":"2014-11-07T02:03:59Z","timestamp":1415325839000},"page":"10773-10812","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":157,"title":["Towards an Operational SAR-Based Rice Monitoring System in Asia: Examples from 13 Demonstration Sites across Asia in the RIICE Project"],"prefix":"10.3390","volume":"6","author":[{"given":"Andrew","family":"Nelson","sequence":"first","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tri","family":"Setiyono","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arnel","family":"Rala","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emma","family":"Quicho","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeny","family":"Raviz","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prosperidad","family":"Abonete","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aileen","family":"Maunahan","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cornelia","family":"Garcia","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hannah","family":"Bhatti","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lorena","family":"Villano","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pongmanee","family":"Thongbai","sequence":"additional","affiliation":[{"name":"International Rice Research Institute (IRRI), Los Ba\u00f1os 4031, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Holecz","sequence":"additional","affiliation":[{"name":"Sarmap, Purasca 6989, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Massimo","family":"Barbieri","sequence":"additional","affiliation":[{"name":"Sarmap, Purasca 6989, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesco","family":"Collivignarelli","sequence":"additional","affiliation":[{"name":"Sarmap, Purasca 6989, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luca","family":"Gatti","sequence":"additional","affiliation":[{"name":"Sarmap, Purasca 6989, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eduardo","family":"Quilang","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mary","family":"Mabalay","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pristine","family":"Mabalot","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mabel","family":"Barroga","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alfie","family":"Bacong","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Norlyn","family":"Detoito","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Glorie","family":"Berja","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frenciso","family":"Varquez","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute (PhilRice), Mu\u00f1oz 3119, Philippines"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"family":"Wahyunto","sequence":"additional","affiliation":[{"name":"Indonesian Center for Agricultural Land Resources Research and Development (ICALRD),  Bogor 16123, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dwi","family":"Kuntjoro","sequence":"additional","affiliation":[{"name":"Indonesian Center for Agricultural Land Resources Research and Development (ICALRD),  Bogor 16123, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sri","family":"Murdiyati","sequence":"additional","affiliation":[{"name":"Indonesian Center for Agricultural Land Resources Research and Development (ICALRD),  Bogor 16123, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sellaperumal","family":"Pazhanivelan","sequence":"additional","affiliation":[{"name":"Directorate of Crop Management, Tamil Nadu Agricultural University (TNAU),  Coimbatore 641003, 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Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amornrat","family":"Intrman","sequence":"additional","affiliation":[{"name":"Thailand Rice Department (TRD), Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thana","family":"Setapayak","sequence":"additional","affiliation":[{"name":"Thailand Rice Department (TRD), Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sommai","family":"Lertna","sequence":"additional","affiliation":[{"name":"Thailand Rice Department (TRD), Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8574-7151","authenticated-orcid":false,"given":"Vo","family":"Minh","sequence":"additional","affiliation":[{"name":"Department of Land Resources, Can Tho University (CTU), Can Tho 92000, 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(2013). Rice Almanac, International Rice Research Institute. [4th ed.]."},{"key":"ref_2","unstructured":"FAO FAOSTAT. Available online:http: \/\/faostat3.fao.org\/faostat-gateway\/go\/to\/home\/E."},{"key":"ref_3","unstructured":"Timmer, C.P. (2010). The Changing Role of Rice in Asia\u2019s Food Security, Asian Development Bank (ADB)."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.rse.2005.10.004","article-title":"Mapping paddy rice agriculture in South and Southeast Asia using multi-temporal MODIS images","volume":"100","author":"Xiao","year":"2006","journal-title":"Remote Sens. Environ."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.isprsjprs.2014.02.007","article-title":"Mapping seasonal rice cropland extent and area in the high cropping intensity environment of Bangladesh using MODIS 500 m data for the year 2010","volume":"91","author":"Gumma","year":"2014","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1111\/agec.12066","article-title":"Did the commodity price spike increase rural poverty? Evidence from a long-run panel in Bangladesh","volume":"45","author":"Balagtas","year":"2014","journal-title":"Agric. Econ."},{"key":"ref_7","unstructured":"Mittal, A. (2009). The 2008 Food Price Crisis: Rethinking Food Security Policies, United Nations."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.gfs.2012.09.001","article-title":"Why stable food prices are a good thing: Lessons from stabilizing rice prices in Asia","volume":"1","author":"Dawe","year":"2012","journal-title":"Glob. Food Sec."},{"key":"ref_9","unstructured":"Huke, R.E., and Huke, E.H. (1997). Rice Area by Type of Culture: South, Southeast, and East Asia, A Revised and Updated Data Base, International Rice Research Institute."},{"key":"ref_10","unstructured":"NASA Cloud Fraction, Available online:http: \/\/neo.sci.gsfc.nasa.gov\/view.php?datasetId=MODAL2_M_CLD_FR."},{"key":"ref_11","unstructured":"Pandey, S., Byerlee, D., Dawe, D., Dobermann, A., Mohanty, S., Rozelle, S., and Hardy, B. (2010). Rice in the Global Economy: Strategic Research and Policy Issues for Food Security, International Rice Research Institute (IRRI)."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1080\/01431161.2010.532826","article-title":"Mapping the irrigated rice cropping patterns of the Mekong delta, Vietnam, through hyper-temporal SPOT NDVI image analysis","volume":"33","author":"Nguyen","year":"2012","journal-title":"Int. J. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e88741","DOI":"10.1371\/journal.pone.0088741","article-title":"Comparative analysis of normalised difference spectral indices derived from MODIS for detecting surface water in flooded rice cropping systems","volume":"9","author":"Boschetti","year":"2014","journal-title":"PLoS One"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1109\/36.551933","article-title":"Rice crop mapping and monitoring using ERS-1 data based on experiment and modeling results","volume":"35","author":"Ribbes","year":"1997","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_15","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_16","doi-asserted-by":"crossref","first-page":"710410","DOI":"10.1117\/12.800051","article-title":"Rice crop monitoring using X-, C- and L-band SAR data","volume":"7104","author":"Suga","year":"2008","journal-title":"Proc. SPIE"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"517","DOI":"10.1109\/TGRS.2008.2007963","article-title":"Monitoring of the rice cropping system in the Mekong delta using ENVISAT\/ASAR dual polarization data","volume":"47","author":"Bouvet","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2714","DOI":"10.1109\/TGRS.2009.2014053","article-title":"Polarimetric backscattering coefficients of flooded rice fields at L- and C-bands: Measurements, modeling, and data analysis","volume":"47","author":"Oh","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_19","first-page":"31","article-title":"Estimation of paddy rice growth parameters using L-, C-, X-bands polarimetric scatterometer","volume":"25","author":"Kim","year":"2009","journal-title":"Korean J. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1109\/JSTARS.2010.2047634","article-title":"First results of rice monitoring practices in Spain by means of time series of TerraSAR-X dual-pol images","volume":"4","author":"Hajnsek","year":"2011","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2695","DOI":"10.1109\/TGRS.2011.2176740","article-title":"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_22","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1080\/2150704X.2012.725482","article-title":"Relationship between X-band backscattering coefficients from high-resolution satellite SAR and biophysical variables in paddy rice","volume":"4","author":"Inoue","year":"2013","journal-title":"Remote Sens. Lett."},{"key":"ref_23","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_24","unstructured":"Liew, S.C., Kam, S.P., Tuong, T.P., Chen, P., Minh, V.Q., and Lim, H. (1997, January 3\u20138). Landcover classification over the Mekong river delta using ERS and RADARSAT SAR images. Proceedings of the 1997 IEEE International Geoscience and Remote Sensing \u201cRemote Sensing\u2014A Scientific Vision for Sustainable Development\u201d (IGARSS \u201997)."},{"key":"ref_25","unstructured":"Holecz, F., Barbieri, M., Collivignarelli, F., Gatti, L., Nelson, A., Setiyono, T.D., Boschetti, M., Manfron, G., Brivio, P.A., and Quilang, J.E. (2013, January 9\u201311). An operational remote sensing based service for rice production estimation at national scale. Proceedings of the Living Planet Symposium 2013, Edinburgh, UK."},{"key":"ref_26","unstructured":"Yoshida, S. (1981). Fundamentals of Rice Crop Science, International Rice Research Institute (IRRI)."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1080\/00031305.1978.10479265","article-title":"A note on Sample size estimation for multinomial populations","volume":"32","author":"Tortora","year":"1978","journal-title":"Am. Stat."},{"key":"ref_28","unstructured":"De Grandi, G.F., Leysen, M., Lee, J.S., and Schuler, D. (1997, January 3\u20138). Radar reflectivity estimation using multiple SAR scenes of the same target: Technique and applications. Proceedings of the 1997 IEEE International Geoscience and Remote Sensing \u201cRemote Sensing\u2014A Scientific Vision for Sustainable Development\u201d (IGARSS \u201997), Singapore."},{"key":"ref_29","unstructured":"Aspert, F., Bach-Cuadra, M., Cantone, A., Holecz, F., and Thiran, J.-P. (2007, January 23\u201327). Time-varying segmentation for mapping of land cover changes. Proceedings of ENVISAT Symposium, Montreux, Switerland."},{"key":"ref_30","unstructured":"RIICE. Available online:http:\/\/www.riice.org."},{"key":"ref_31","unstructured":"Asia-RiCE. Available online:http:\/\/asia-rice.org."},{"key":"ref_32","unstructured":"GEOGLAM Crop Monitor. Available online:http:\/\/www.geoglam-crop-monitor.org."},{"key":"ref_33","unstructured":"Innovative Data Collection Methods for Agricultural and Rural Statistics. Available online:http:\/\/www.adb.org\/projects\/46399-001\/main."},{"key":"ref_34","unstructured":"ERMES. Available online:http:\/\/www.ermes-fp7space.eu."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Rosenqvist, A., Shimada, M., Suzuki, S., Ohgushi, F., Tadono, T., Watanabe, M., Tsuzuku, K., Watanabe, T., Kamijo, S., and Aoki, E. (2014). Operational performance of the ALOS global systematic acquisition strategy and observation plans for ALOS-2 PALSAR-2. Remote Sens. Environ.","DOI":"10.1016\/j.rse.2014.04.011"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/6\/11\/10773\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:09:01Z","timestamp":1760216941000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/6\/11\/10773"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,11,6]]},"references-count":35,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2014,11]]}},"alternative-id":["rs61110773"],"URL":"https:\/\/doi.org\/10.3390\/rs61110773","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,11,6]]}}}