Harbour dredging and fish mortality in an aquaculture zone: assessment of changes in suspended particulate matter using multi-sensor remote-sensing data

The semi-closed Rushan Bay is one of the largest aquaculture bases in North China, with its only navigation channel connecting the Rushan harbour and the Yellow Sea. Recent economic growth with increased import and export demands have stimulated a dredging operation, starting on 26 March 2010, which was paused on 17 June 2010 after numerous reports of mortality of cultured shellfish, such as clam (Ruditapes philippinarum), among other precious marine animals. A lawsuit was filed to settle the dispute between the dredging company and an aquaculture company, yet there was endless debate on whether the mortality was caused by the dredging operations. Here, using multi-sensor remote-sensing data collected by Landsat/ETM+, HJ-1A&1 B/CCD, and Aqua & Terra/MODIS, we addressed the two critical questions of (1) whether there was a significant increase in the suspended particulate matter (SPM) in the aquaculture area during and after the dredging operations; and (2) if the answer is yes, whether such an increase wa...