Salt marshes are one of the most powerful carbon sinks on the planet; burying carbon at a rate ~55 times faster than tropical rainforests. Nevertheless, despite their value as carbon sinks, salt marshes have undergone rapid global decline raising concerns that society is losing an important carbon sink, and that large amounts of ancient buried C are being released into the atmosphere as CO2 and contributing to global warming.
At UNEP-WCMC, as part of the GEF Blue Forests Project, we are developing the first global map of salt marsh distribution. This map will allow the first global assessment of salt marsh status (extent and management) and serve as a baseline for future gain/loss assessments and a tool from which assessments of use, threats, management, etc. can be made. In addition, we are compiling estimates of organic carbon stocks in tidal salt marshes and will use the newly developed global map to provide a global estimate.
The Blue Carbon Toolkit integrates both online (web-based) and offline (tablet-based) technology for assessing and validating coastal ‘blue carbon’ habitats. It is envisioned that government departments and businesses will be able to use these tools to broadly assess the impact of development on coastal marine habitats and the associated blue carbon stock, helping to make informed decisions on future development. The online assessment tool is the public facing, front end of the Toolkit. It allows users to create one or more areas of interest on a satellite map of the implementation sites. They then receive information on the habitat extent and associated carbon stored in the vegetation and soil. The online validation tool is the administrative, back end of the Toolkit. It allows scientists and managers to validate and update the spatial habitat extent based on the underlying satellite imagery, local knowledge or data received from field observations. Scientists can also conduct validations in the field using an offline, tablet-based validation tool which has been developed to support field-based work. When there is a connection, habitat data is updated and presented on the online tools, ensuring that the latest information is displayed at all times.
By Chris Mcowen, UNEP-WCMC