Recent studies have highlighted that freshwater salinization is a global issue with a multitude of causes including: road salt application and runoff, wastewater, climate change-enhanced mineral weathering, mining, fertilizer application, construction, evaporation and desiccation, and seawater intrusion. Salinization represents a major perturbation to freshwater biota as well as for biogeochemical cycling. More studies are now highlighting the significant implications of salinization for freshwater biogeochemistry, especially for greenhouse gas and nutrient cycling dynamics, because of the modification of water column density and mixing. Much work has recently been done in Canada revealing the extent of freshwater salinization and the different causes across Canada. This session invites contributions from experts in limnology, hydrology, hydrogeology, biogeochemistry, greenhouse gas dynamics and environmental chemistry to share their findings about the causes, extent, and cumulative and coupled impacts on biogeochemistry and/or biota of freshwater salinization in Canada. This session will take stock of the geographic extent and diversity of the freshwater salinization problem in Canada. Examples of topics could include: analysis of the impact of salinization on mixing regimes and nutrient cycling and greenhouse gas dynamics in different water bodies such as ponds and lakes, hydrogeological investigations into the extent of groundwater salinization; spatial analyses of sources of salinization within and across watersheds; temporal analyses of salinity time series for different water bodies; and lab-scale and field-scale investigations into the interactions between mineralogy hydrology and biogeochemistry in groundwater and/or soil during salinization. Field, laboratory, and/or modeling studies done at any scale are all welcome.