{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T23:06:28Z","timestamp":1768691188020,"version":"3.49.0"},"reference-count":61,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T00:00:00Z","timestamp":1678838400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Director Fund of the International Research Center of Big Data for Sustainable Development Goals","award":["CBAS2022DF004"],"award-info":[{"award-number":["CBAS2022DF004"]}]},{"name":"Director Fund of the International Research Center of Big Data for Sustainable Development Goals","award":["41901272"],"award-info":[{"award-number":["41901272"]}]},{"name":"Director Fund of the International Research Center of Big Data for Sustainable Development Goals","award":["ZDKJ2019006"],"award-info":[{"award-number":["ZDKJ2019006"]}]},{"name":"Director Fund of the International Research Center of Big Data for Sustainable Development Goals","award":["59193"],"award-info":[{"award-number":["59193"]}]},{"name":"National Natural Science Foundation of China","award":["CBAS2022DF004"],"award-info":[{"award-number":["CBAS2022DF004"]}]},{"name":"National Natural Science Foundation of China","award":["41901272"],"award-info":[{"award-number":["41901272"]}]},{"name":"National Natural Science Foundation of China","award":["ZDKJ2019006"],"award-info":[{"award-number":["ZDKJ2019006"]}]},{"name":"National Natural Science Foundation of China","award":["59193"],"award-info":[{"award-number":["59193"]}]},{"name":"Hainan Provincial Department of Science and Technology","award":["CBAS2022DF004"],"award-info":[{"award-number":["CBAS2022DF004"]}]},{"name":"Hainan Provincial Department of Science and Technology","award":["41901272"],"award-info":[{"award-number":["41901272"]}]},{"name":"Hainan Provincial Department of Science and Technology","award":["ZDKJ2019006"],"award-info":[{"award-number":["ZDKJ2019006"]}]},{"name":"Hainan Provincial Department of Science and Technology","award":["59193"],"award-info":[{"award-number":["59193"]}]},{"name":"Dragon 5 Cooperation","award":["CBAS2022DF004"],"award-info":[{"award-number":["CBAS2022DF004"]}]},{"name":"Dragon 5 Cooperation","award":["41901272"],"award-info":[{"award-number":["41901272"]}]},{"name":"Dragon 5 Cooperation","award":["ZDKJ2019006"],"award-info":[{"award-number":["ZDKJ2019006"]}]},{"name":"Dragon 5 Cooperation","award":["59193"],"award-info":[{"award-number":["59193"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Freshwater on islands represents a precious resource and highly vulnerable ecosystem. For monitoring freshwater, satellite remote sensing is efficient and has large-scale application. This study proposed a modified model of the quasi-analytical algorithm (ZSD-QAAv6m) to retrieve the water clarity of inland waters (&gt;1 km2) across Hainan Island, China using Sentinel-2 multispectral instrument data. By adjusting the threshold of Rrs(665), the proposed model could accurately estimate water clarity with diverse optical properties on the island and avoid underestimation in moderately clear waters. Based upon this, the first spatiotemporal analysis of recent water clarity in Hainan Island was conducted. The results show that lake water clarity in the central region was generally higher (with average value of 1.4 m) than that of coastal regions (with average value of 1.2 m). Seasonally, the water clarity during the wet season was usually lower than that in the dry season, with average values of 1.1 m and 1.3 m across the island respectively. From 2017 to 2021, the proportion of water bodies with water clarity &gt; 0.5 m increased from 60% to 100%. The overall spatial pattern of water clarity was correlated to the regional vegetation cover in Hainan Island, with higher clarity associated with higher vegetation cover in the central regions. The seasonal variation of water clarity may be attributed to heavy rainfall and runoff during the wet season; while the distinct annual variation may be benefited from the strengthened surface water protections in Hainan Province in recent years. This study provides a practical approach for evaluating the SDG 6.3.2 indicator in Hainan Island using remote sensed water clarity as a comprehensive water quality indicator and the findings could facilitate the island\u2019s water resource management and conservation.<\/jats:p>","DOI":"10.3390\/rs15061600","type":"journal-article","created":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T06:36:36Z","timestamp":1678862196000},"page":"1600","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Sentinel-2 MSI Observations of Water Clarity in Inland Waters across Hainan Island and Implications for SDG 6.3.2 Evaluation"],"prefix":"10.3390","volume":"15","author":[{"given":"Ruiting","family":"Qiu","sequence":"first","affiliation":[{"name":"School of Earth Science and Resources, China University of Geoscience, Beijing 100083, China"},{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China"}]},{"given":"Shenglei","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China"}]},{"given":"Jiankang","family":"Shi","sequence":"additional","affiliation":[{"name":"Center of Ecology Environment Monitoring of Hainan Province, Haikou 571126, China"}]},{"given":"Wei","family":"Shen","sequence":"additional","affiliation":[{"name":"School of Earth Science and Resources, China University of Geoscience, Beijing 100083, China"}]},{"given":"Wenzhi","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China"},{"name":"International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"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 100094, China"},{"name":"International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China"}]},{"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 100094, China"},{"name":"International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,15]]},"reference":[{"key":"ref_1","first-page":"35","article-title":"Present Situation and Development and Utilization of Water Resources in Hainan Province","volume":"22","author":"Zhou","year":"2004","journal-title":"J. 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