Introduction  
 

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://mel2.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, XMAS-IV, 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.

MEL was established in 2005 under the sponsorship of the Ministry of Science and Technology of China (MOST). It has been awarded The Excellent State Key Laboratory twice in the two recent official reviews by the MOST. MEL is dedicated to interdisciplinary cutting-edge research in marine environmental sciences, with particular strengths in marine biogeochemistry and ecosystem studies.

Originally known as Amoy, Xiamen is a renowned littoral tour city for its cultural relics, pleasant climate, and beautiful natural sceneries. It is located on the southeast coast of China with a long history of international commerce. It has a monsoonal humid subtropical climate featured by mild and dry winters. (average January temperature around 15 °C (59 °F).