To promote interdisciplinary studies in marine environmental science and to foster the next generation of ocean scientists, the State Key Laboratory of Marine Environmental Science, Xiamen University (MEL) in 2014 initiated Xiamen Symposium on Marine Environmental Sciences (XMAS) which has grown to be one of Asia’s largest conferences in marine sciences to exchange research interests in global and regional oceans.

XMAS 2025 will be held from January 14th to 17th, 2025 in Xiamen, China and is organized by the MEL and Department of Earth Sciences, National Natural Science Foundation of China (NSFC). Furthermore, for the first time, the symposium will be co-sponsored by Association for the Sciences of Limnology and Oceanography (ASLO). XMAS 2025 will consist of interdisciplinary cutting-edged sessions covering physical, chemical, and biological oceanography as well as marine toxicology. In addition, workshops on emerging topics in marine environmental sciences such as ocean-based carbon removal, ocean governance and sustainability, the marine economy, marine education and outreach, and special sessions on Women in Science and mentoring future scientists will also be offered. All of these will feature ASLO members in addition to experts in these respective fields from around the world.

MEL was established in 2005 under sponsorship from the Ministry of Science and Technology of China (MOST). It has been awarded the Excellent State Key Laboratory in two recent consecutive official reviews by 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 coastal city renowned for rich cultural relics, a pleasant climate, and beautiful natural scenery. It is located on the southeast coast of China and has a long history of international commerce. Xiamen won the "United Nations Habitat Scroll of Honor Award" as well as the titles of the "International Garden City" and one of "National Model City for Environmental Protection". Its clean, tidy and sanitary environment, civilized and polite citizens and a natural and beautiful environment have formed the city's harmonious, quiet and peaceful features and atmosphere. It has a monsoonal humid subtropical climate characterized by mild and dry winters, with an average temperature around 15 °C (59 °F) in January.