eprintid: 10107313 rev_number: 22 eprint_status: archive userid: 608 dir: disk0/10/10/73/13 datestamp: 2020-08-11 13:33:49 lastmod: 2021-09-17 22:30:22 status_changed: 2020-08-11 13:33:49 type: article metadata_visibility: show creators_name: Liu, D creators_name: Duan, H creators_name: Loiselle, S creators_name: Hu, C creators_name: Zhang, G creators_name: Li, J creators_name: Yang, H creators_name: Thompson, JR creators_name: Cao, Z creators_name: Shen, M creators_name: Ma, R creators_name: Zhang, M creators_name: Han, W title: Observations of water transparency in China's lakes from space ispublished: pub divisions: UCL divisions: B03 divisions: C03 divisions: F26 keywords: Science & Technology, Technology, Remote Sensing, Water transparency, Chinese lakes, Spatio-temporal variation, Water depth, Vegetation restoration, LONG-TERM MODIS, INLAND WATERS, LANDSAT IMAGERY, CLIMATE-CHANGE, SHALLOW LAKES, CLARITY, PHYTOPLANKTON, CARBON, RIVER, RESUSPENSION note: This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/). abstract: Water transparency, usually denoted by Secchi disk depth (SSD), represents the first-order description of water quality and has important implications for the diversity and productivity of aquatic life. In China, lakes supply freshwater and ecosystem services to nearly a billion people. Therefore, real time monitoring of lake transparency is of great significance. Moreover, understanding how and why transparency varies in space and time in response to different driving forces is needed to understand, manage, and predict lake water quality. Based on the time-saving and low-cost Google Earth Engine cloud platform, this study developed a new algorithm for quickly mapping SDDs in Chinese lakes. SDDs were retrieved for 412 Chinese lakes (> 20 km2) for the period 2000–2018. Results demonstrated that lake water depth spatially differentiated transparency. Deep lakes usually had high transparency and water depth explained 88.81 % of the spatial variations. With increasing catchment vegetation coverage and lake water depth, 70.15 % of lakes witnessed increasing transparency during 2000–2018. Of these 42.72 % were significant (p<0.05). Transparency of deep lakes was generally determined by phytoplankton density not sediment resuspension. Minimum transparency occurred in summer. Future increases in lake water levels in response to factors such as climate change may contribute to further improvements in transparency. Management should focus on controlling eutrophication and increasing vegetation cover in catchments. date: 2020-10-01 date_type: published publisher: ELSEVIER official_url: https://doi.org/10.1016/j.jag.2020.102187 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1806683 doi: 10.1016/j.jag.2020.102187 lyricists_name: Thompson, Julian lyricists_id: JRTHO32 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner full_text_status: public publication: International Journal of Applied Earth Observation and Geoinformation volume: 92 article_number: 102187 pages: 11 citation: Liu, D; Duan, H; Loiselle, S; Hu, C; Zhang, G; Li, J; Yang, H; ... Han, W; + view all <#> Liu, D; Duan, H; Loiselle, S; Hu, C; Zhang, G; Li, J; Yang, H; Thompson, JR; Cao, Z; Shen, M; Ma, R; Zhang, M; Han, W; - view fewer <#> (2020) Observations of water transparency in China's lakes from space. International Journal of Applied Earth Observation and Geoinformation , 92 , Article 102187. 10.1016/j.jag.2020.102187 <https://doi.org/10.1016/j.jag.2020.102187>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10107313/1/1-s2.0-S0303243420304049-main.pdf