To foster knowledge and ideas exchange within the marine environmental science community and, in particular, to promote interdisciplinary studies, the State Key Laboratory of Marine Environmental Science (MEL, http://mel.xmu.edu.cn/en) of Xiamen University initiated the Xiamen Symposium on Marine Environmental Sciences (XMAS), with the overarching theme of The Changing Ocean Environment: From a Multidisciplinary Perspective. The XMAS-III (http://mel.xmu.edu.cn/conference/3xmas/) was held in Jan 2017, attracting over 620 participants from more than 140 institutions across 21 countries. 

The fourth iteration, XMAS2019 will be held in Xiamen from January 6th to 9th, 2019. The symposium will consist of different, interconnected sessions covering physical oceanography, marine biogeochemistry, biological oceanography, and marine ecotoxicology along with workshops for emerging topics in marine environmental sciences.