1. Introduction 2. Leaf litter, wood and root decomposition and carbon mineralization 3. Greenhouse gas emission from the sediment-air interface: a review 4. Biosphere-atmosphere greenhouse gas fluxes at the ecosystem scale 5. Macrofaunal consumption 6. Greenhouse gas emissions from the water-air interface 7. The impact of climate change on greenhouse gas emission 8. The role of biogenic structures for greenhouse gas balance in intertidal wetlands 9. Greenhouse gas emission from anthropogenic disturbances 10. Carbon storage and mineralization in coastal wetlands