Satellite observations of suspended sediment near Ningbo North Dyke, China.

We investigated the impact of the Ningbo North Dyke (NND) built in 2012–2014 in the coastal waterway of East China Sea on local suspended sediment concentration (SSC). Several multi-spectral satellite images acquired by the Landsat Thematic Mapper (TM)/Operational Land Imager (OLI) in 2008–2017 were used. We analyzed the change of SSC and spectral curves of study area around small NND (the NND's total length less than 1 km) using a prior model proposed in our previous study. We found that SSC near NND in the Meishan Waterway decreased after the NND construction by 200–300 mg/l, so that clean blue water is now observed in the Meishan Waterway, apparently thanks to stable dynamic environment in presence of NND. Our results reveal the impact of a small coastal dyke with length less than 1 km on the movement and distribution of SSC from a remote-sensing perspective. [ABSTRACT FROM AUTHOR]