Mercury (Hg) contamination continues to be an environmental and public health concern. Processes of Hg transport, methylation, and biotic uptake shift through time and space. The goal of this session is to highlight recent scientific advances in Hg cycling in relation to environmental change. Abstracts will be considered on a variety of topics including: Hg speciation, biogeochemistry, and bioaccumulation in terrestrial, freshwater, and marine ecosystems. Papers that consider the role of environmental change, climate, ecosystem response, scale, source apportionment, food web dynamics, and biotic and abiotic controls on Hg cycling and bioaccumulation are strongly encouraged.