Carbon sequestration in wetlands, from science to practice: An overview of the biogeochemical process, measurement methods, and policy framework

[Display omitted] •This study intends to build bridges between science, policy, and practice.•Despite of covering a small portion of the landscape, wetlands are key carbon sinks.•Hydrogeomophology drives the relation between C sequestration vs sediment accretion.•Despite being a large C sink, tropical wetlands are underrepresented in literature.•Policy and management should address how net GHG emissions differ with wetland type. Ecosystem services are becoming increasingly important and a reason to promote the sustainable use of natural resources. Wetlands provide many valuable ecosystem services, including carbon (C) sequestration. Wetlands are an important C sink, playing a key role in climate regulation. As such, their ability to sequester C is being considered in national GHG emissions assessments and private initiatives as a potential source of revenue to manage carbon-balanced landscapes and pay for ecosystem services. To be able to implement these initiatives widely some aspects of wetland carbon science and practice still need to be formalized and standardized. Here we synthesize the scientific basis of the biogeochemical processes that drive C sequestration in wetlands and assess the methods available for its measurement. We have reviewed data in 110 peer-reviewed studies form wetlands around the world and provide an overview of the current policies and guidelines in which C sequestration in wetlands is framed as an ecosystem management practice. The intention of this review is to provide a wide and comprehensive summary of C sequestration in wetlands, from science to practice. This analysis can help inform practitioners and landscape managers in future considerations regarding project design and policy implementation, improve current climate mitigation schemes and payment for ecosystem services frameworks, and foster the worldwide implementation of wetland restoration, creation, and conservation projects for sustainable development and climate change mitigation and adaptation.