Greenhouse gas fluxes are geographically highly heterogeneous, and habitats that represent small areas can make important contributions to landscape-scale greenhouse gas (GHG) balances. In the case of inland waters, carbon compounds are transported laterally from catchments to streams, rivers and lakes where large amounts of carbon are emitted as carbon dioxide (CO2) or methane (CH4) to the atmosphere, buried in the sediments resulting in a carbon sink, or flushed to the coast. Recent studies indicate that continental carbon fluxes and GHG balance cannot be adequately assessed without considering the contribution of inland waters. We here invite presentations on carbon and GHG fluxes of various environments, which integrate or compare ecosystems, and assess how they contribute to landscape-level GHG budgets, as well as studies of methodological aspects including e.g. measurements, data analysis, and scaling. The session is inspired by recent progress on carbon compounds from natural and anthropogenic inland waters including lakes, streams, and reservoirs, but studies of other types of environments or of non-carbon GHGs are also strongly encouraged.