{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T16:49:03Z","timestamp":1772902143812,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T00:00:00Z","timestamp":1623196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008111","name":"Hainan Provincial Department of Science and Technology","doi-asserted-by":"publisher","award":["ZDKJ2019006"],"award-info":[{"award-number":["ZDKJ2019006"]}],"id":[{"id":"10.13039\/501100008111","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Service Network Initiative, Chinese Academy of Sciences","award":["KFJ-STS-ZDTP-077"],"award-info":[{"award-number":["KFJ-STS-ZDTP-077"]}]},{"name":"Open Research Fund of National Earth Observation Data Center","award":["No.NODAOP2020017"],"award-info":[{"award-number":["No.NODAOP2020017"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["419713184"],"award-info":[{"award-number":["419713184"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Dragon 5 Cooperation","award":["No.59193"],"award-info":[{"award-number":["No.59193"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Yangtze River is the third longest river in the world. Monitoring and protecting its water quality are important for economic and social development. Water clarity (Secchi disk depth, SDD) is an important reference index for evaluating water quality. In this study, Sentinel-2 multispectral instrument (MSI) remote sensing images were utilized together with the Forel-Ule index (FUI) and hue angle \u03b1 to construct an SDD retrieval model, which was applied to the Yangtze River from 2017 to 2020, which was used to describe color in the International Commission on Illumination (CIE) color space to construct an SDD retrieval model that was applied to the Yangtze River for the period 2017\u20132020. Further, the spatial distribution, seasonal variation, inter-annual variation, and driving factors of the observed SDD variations were analyzed. The spatial distribution pattern of the Yangtze River was high in the west and low in the east. The main driving factors affecting the Yangtze River SDD was sediment runoff, water level, and precipitation. The upstream and downstream Yangtze River SDD were negatively correlated with the change in water level and sediment runoff, whereas the midstream Yangtze River SDD was positively correlated with the change in water level and sediment runoff. The upper and lower reaches of the Yangtze River and overall SDD showed a weak downward trend, and the middle reaches of the Yangtze River remained almost unchanged.<\/jats:p>","DOI":"10.3390\/rs13122260","type":"journal-article","created":{"date-parts":[[2021,6,9]],"date-time":"2021-06-09T14:16:04Z","timestamp":1623248164000},"page":"2260","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Retrieval and Spatio-Temporal Variations Analysis of Yangtze River Water Clarity from 2017 to 2020 Based on Sentinel-2 Images"],"prefix":"10.3390","volume":"13","author":[{"given":"Yelong","family":"Zhao","sequence":"first","affiliation":[{"name":"School of Geomatics, Liaoning Technical University, Fuxin 123000, China"},{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shenglei","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9628-1817","authenticated-orcid":false,"given":"Fangfang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qian","family":"Shen","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8590-9736","authenticated-orcid":false,"given":"Junsheng","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Key Laboratory of Earth Observation Hainan Province, Sanya 572029, China"},{"name":"School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,9]]},"reference":[{"key":"ref_1","unstructured":"The Yangtze River Water Conservancy Commission of the Ministry of Liberia (1999). Atlas of the Yangtze River Basin, Map Publishing House."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"177","DOI":"10.5194\/os-10-177-2014","article-title":"Secchi depth in the Oslofjord-Skagerrak area: Theory, experiments and relationships to other quantities","volume":"10","author":"Aas","year":"2014","journal-title":"Ocean Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"361","DOI":"10.4319\/lo.1977.22.2.0361","article-title":"A trophic state index for lakes","volume":"22","author":"Carlson","year":"1977","journal-title":"Limnol. Oceanogr."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4086","DOI":"10.1016\/j.rse.2007.12.013","article-title":"A 20-Year Landsat water clarity census of Minnesota\u2019s 10,000 lakes","volume":"112","author":"Olmanson","year":"2008","journal-title":"Remote Sens. Environ."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/j.rse.2016.01.007","article-title":"Comparison of Landsat 8 and Landsat 7 for regional measurements of CDOM and water clarity in lakes","volume":"185","author":"Olmanson","year":"2016","journal-title":"Remote Sens. Environ."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"111949","DOI":"10.1016\/j.rse.2020.111949","article-title":"Changes of water clarity in large lakes and reservoirs across China observed from long-term MODIS","volume":"247","author":"Wang","year":"2020","journal-title":"Remote Sens. Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/j.rse.2012.03.006","article-title":"Combining lake and watershed characteristics with Landsat TM data for remote estimation of regional lake clarity","volume":"123","author":"McCullough","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2321","DOI":"10.1002\/lno.10940","article-title":"Resolving the long-standing puzzles about the observed Secchi depth relationships","volume":"63","author":"Lee","year":"2018","journal-title":"Limnol. Oceanogr."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2986","DOI":"10.1016\/j.rse.2011.05.019","article-title":"Ocean transparency from space: Validation of algorithms estimating Secchi depth using MERIS, MODIS and SeaWiFs data","volume":"115","author":"Doron","year":"2011","journal-title":"Remote Sens. Environ."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.rse.2015.02.001","article-title":"Aquatic color radiometry remote sensing of coastal and inland waters: Challenges and recommendations for future satellite missions","volume":"160","author":"Mouw","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Chipman, J.W., Lillesand, T.M., Schmaltz, J.E., Leale, J.E., and Nordheim, M.J. (2004). Mapping lake water clarity with Landsat images in Wisconsin, USA. Can. J. Remote Sens., 30.","DOI":"10.5589\/m03-047"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"27","DOI":"10.4081\/jlimnol.2003.s1.27","article-title":"Regional assessment of lake water clarity using satellite remote sensing","volume":"62","author":"Nelson","year":"2003","journal-title":"J. Limnol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1554","DOI":"10.1016\/j.scitotenv.2018.01.036","article-title":"Remote observation of water clarity patterns in Three Gorges Reservoir and Dongting Lake of China and their probable linkage to the Three Gorges Dam based on Landsat 8 imagery","volume":"625","author":"Ren","year":"2018","journal-title":"Sci. Total Environ."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1007\/s10201-009-0263-y","article-title":"Remote-sensing assessment of regional inland lake water clarity in Northeast China","volume":"10","author":"Duan","year":"2009","journal-title":"Limnology"},{"key":"ref_15","first-page":"671","article-title":"Use of thematic mapper data to assess water quality in Green Bay and central Lake Michigan","volume":"52","author":"Lathrop","year":"1986","journal-title":"Photogramm. Eng. Remote Sens."},{"key":"ref_16","first-page":"465","article-title":"Landsat thematic mapper monitoring of turbid inland water quality","volume":"58","author":"Lathrop","year":"1992","journal-title":"Photogramm. Eng. Remote Sens."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/S0048-9697(00)00692-6","article-title":"Detecting chlorophyll, Secchi disk depth and surface temperature in a sub-alpine lake using landsat imagery","volume":"268","author":"Giardino","year":"2001","journal-title":"Sci. Total Environ."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"4330","DOI":"10.1016\/S0043-1354(02)00146-X","article-title":"Application of Landsat imagery to regional-scale assessments of lake clarity","volume":"36","author":"Kloiber","year":"2002","journal-title":"Water Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1016\/S0034-4257(02)00022-6","article-title":"A procedure for regional lake water clarity assessment using Landsat multispectral data","volume":"82","author":"Kloiber","year":"2002","journal-title":"Remote Sens. Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"437","DOI":"10.1016\/j.ecss.2004.06.019","article-title":"Use of satellite imagery for water quality studies in New York Harbor","volume":"61","author":"Hellweger","year":"2004","journal-title":"Estuar. Coast. Shelf Sci."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Lee, Z.P., Darecki, M., Carder, K.L., Davis, C.O., Stramski, D., and Rhea, W.J. (2005). Diffuse attenuation coefficient of downwelling irradiance: An evaluation of remote sensing methods. J. Geophys. Resour. Oceans, 110.","DOI":"10.1029\/2004JC002573"},{"key":"ref_22","first-page":"C03009","article-title":"Euphotic zone depth: Its derivation and implication to ocean-color remote sensing","volume":"112","author":"Lee","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"828","DOI":"10.3394\/0380-1330(2007)33[828:TIWCOT]2.0.CO;2","article-title":"Trends in water clarity of the lower great lakes from remotely sensed aquatic color","volume":"2","author":"Binding","year":"2007","journal-title":"J. Great Lakes Resour."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"213","DOI":"10.4319\/lo.2001.46.2.0213","article-title":"Remote sensing of biotic effects: Zebra mussels (Dreissena polymorpha) influence on water clarity in Saginaw Bay, Lake Huron","volume":"46","author":"Budd","year":"2001","journal-title":"Limnol. Oceanogr."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"26","DOI":"10.5589\/m03-049","article-title":"SeaWiFS global composite images show significant features of Canadian waters for 1997\u20132201","volume":"30","author":"Gower","year":"2004","journal-title":"Can. J. Remote Sens."},{"key":"ref_26","first-page":"287","article-title":"Deteriorating water clarity in shallow waters: Evidence from long term MODIS in-situ observations","volume":"68","author":"Shi","year":"2018","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1016\/j.rse.2013.10.002","article-title":"Influence of the Three Gorges Dam on total suspended matters in the Yangtze Estuary and its adjacent coastal waters: Observations from MODIS","volume":"140","author":"Feng","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Shi, H.Y., Gao, C., Dong, C.M., Xia, C.S., and Xu, G.L. (2017). Variations of river islands around a large city along the Yangtze River from satellite remote sensing images. Sensors, 17.","DOI":"10.3390\/s17102213"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1082","DOI":"10.1002\/esp.1795","article-title":"Retrieval of suspended sediment concentrations in large turbid rivers using Landsat ETM+: An example from the Yangtze River, China","volume":"34","author":"Wang","year":"2009","journal-title":"Earth Surf. Process. Landf."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/j.rse.2016.12.006","article-title":"Fifteen-year monitoring of the turbidity dynamics in large lakes and reservoirs in the middle and lower basin of the Yangtze River, China","volume":"190","author":"Hou","year":"2017","journal-title":"Remote Sens. Environ."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Zhu, H., Zhu, J.S., and Zou, Q. (2020). Comprehensive analysis of coordination relationship between water resources environment and high-quality economic development in urban agglomeration in the middle reaches of Yangtze River. Water, 12.","DOI":"10.3390\/w12051301"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"110864","DOI":"10.1016\/j.marpolbul.2019.110864","article-title":"Assessment of heavy metals in water, sediment and shellfish organisms in typical areas of the Yangtze River Estuary, China","volume":"151","author":"Fan","year":"2020","journal-title":"Mar. Pollut. Bull."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"142838","DOI":"10.1016\/j.scitotenv.2020.142838","article-title":"Contribution of the offshore detached Changjiang (Yangtze River) diluted water to the formation of hypoxia in summer","volume":"764","author":"Wei","year":"2021","journal-title":"Sci. Total Environ."},{"key":"ref_34","first-page":"287","article-title":"Evaluation and spatial-temporal dynamics change of water resources carrying capacity in the Yangtze River economic belt","volume":"26","author":"He","year":"2019","journal-title":"Res. Soil Water Conserv."},{"key":"ref_35","first-page":"81","article-title":"Water environment issues and pollution prevention strategies in Wuhan reach of Fu River","volume":"43","author":"Yin","year":"2018","journal-title":"Environ. Sci. Manag."},{"key":"ref_36","first-page":"371","article-title":"Impact of climate change and human activities on water storage changes in the Yangtze River Basin","volume":"39","author":"Tian","year":"2019","journal-title":"J. Geod. Geodyn."},{"key":"ref_37","first-page":"1","article-title":"Coupling coordination between urbanization and water resources in Yangtze River economic zone","volume":"21","author":"Shen","year":"2019","journal-title":"Resour. Ind."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.rse.2017.05.041","article-title":"The optical trapezoid model: A novel approach to remote sensing of soil moisture applied to Sentinel-2 and Landsat-8 observations","volume":"198","author":"Sadeghi","year":"2017","journal-title":"Remote Sens. Environ."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Zhao, Y.L., Shen, Q., Wang, Q., Yang, F., Wang, S.L., Li, J.S., Zhang, F.F., and Yao, Y. (2020). Recognition of Water Colour Anomaly by Using Hue Angle and Sentinel-2 Image. Remote Sens., 12.","DOI":"10.3390\/rs12040716"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Zhao, Y.L., Wang, S.L., Zhang, F.F., Shen, Q., Li, J.S., and Yang, F. (2021). Remote Sensing-Based Analysis of Spatial and Temporal Water Colour Variations in Baiyangdian Lake After the Establishment of the Xiong\u2019an New Area. Remote Sens., 13.","DOI":"10.3390\/rs13091729"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1016\/j.rse.2017.08.033","article-title":"Sentinel-2 Multispectral Instrument (MSI) data processing for aquatic science applications: Demonstrations and validations","volume":"201","author":"Pahlevan","year":"2017","journal-title":"Remote Sens. Environ."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1007\/s11769-006-0026-1","article-title":"Quantitative modeling of suspended sediment in middle Changjiang River from MODIS","volume":"16","author":"Liu","year":"2006","journal-title":"Chin. Geogr. Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1186\/s12302-020-00359-w","article-title":"Seasonal variability of stable isotopes in the Changjiang (Yangtze) River water and its implications for natural climate and anthropogenic impacts","volume":"32","author":"Li","year":"2020","journal-title":"Environ. Sci. Eur."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"370","DOI":"10.1016\/j.scib.2019.03.002","article-title":"Stable classification with limited sample: Transferring a 30m resolution sample set collected in 2015 to mapping 10 m resolution global land cover in 2017","volume":"64","author":"Gong","year":"2019","journal-title":"Sci. Bull."},{"key":"ref_45","first-page":"73","article-title":"A robust multi-band water index (MBWI) for automated extraction of surface water from Landsat 8 OLI imagery","volume":"68","author":"Wang","year":"2018","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.knosys.2016.06.031","article-title":"An efficient approximation to the k-means clustering for massive data","volume":"117","author":"Lozano","year":"2017","journal-title":"Knowl. Based Syst."},{"key":"ref_47","unstructured":"CIE (Commission International de l\u2019Eclairage) (1931). Proceedings, Cambridge University Press."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1109\/JSTARS.2014.2360564","article-title":"MODIS- Based radiometric color extraction and classification of inland water with the Forel-Ule scale: A case study of Lake Taihu","volume":"8","author":"Wang","year":"2015","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"2206","DOI":"10.1111\/gcb.12854","article-title":"Decrease in water clarity of the Southern and Central North Sea during the 20th-century","volume":"21","author":"Capuzzo","year":"2015","journal-title":"Glob. Chang. Biol."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Fleming-Lehtinen, V., and Laamanen, M. (2012). Long-term changes in Secchi depth and the role of phytoplankton in explaining light attenuation in the Baltic Sea. Estuar. Coast. Shelf Sci., 102\u2013103.","DOI":"10.1016\/j.ecss.2012.02.015"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1016\/j.jhydrol.2011.08.045","article-title":"Annual and interannual variations in terrestrial water storage during and following a period of drought in South Carolina, USA","volume":"409","author":"Billah","year":"2011","journal-title":"J. Hydrol."},{"key":"ref_52","first-page":"54","article-title":"Impacts of climate change and human activities on flow discharge and sediment load in the Yangtze River","volume":"43","author":"Peng","year":"2018","journal-title":"J. Sediment Res."},{"key":"ref_53","first-page":"467","article-title":"Influence of sediment trapping in reservoirs on runoff and sediment discharge variations in Yangtze River","volume":"25","author":"Wang","year":"2014","journal-title":"Adv. Water Sci."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"10285","DOI":"10.1109\/TGRS.2019.2933251","article-title":"Novel Spectral-Derived Features for Empirical Retrieval of Water Quality Parameters: Demonstrations for OLI, MSI, and OLCI Sensors","volume":"57","author":"Bovolo","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Gholizadeh, M.H., Melesse, A.M., and Reddi, L. (2016). A Comprehensive Review on Water Quality Parameters Estimation Using Remote Sensing Techniques. Sensors, 16.","DOI":"10.3390\/s16081298"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/12\/2260\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:12:32Z","timestamp":1760163152000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/12\/2260"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,9]]},"references-count":55,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["rs13122260"],"URL":"https:\/\/doi.org\/10.3390\/rs13122260","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,9]]}}}