A global map of saltmarshes

Area of Science:

• Ecology
• Environmental Science
• Conservation Biology

Background:

• Saltmarshes are vital coastal ecosystems providing essential services like fish production, carbon storage, and coastal protection.
• Despite their importance, the global distribution and extent of saltmarshes remain incompletely understood.
• Increasing pressures on coastal ecosystems necessitate comprehensive global data for effective management and conservation.

Purpose of the Study:

• To compile the most complete global dataset on saltmarsh occurrence and extent.
• To provide a foundational dataset for resource management and conservation decision-making.
• To support progress tracking for international conservation targets.

Main Methods:

• Collated 350,985 individual saltmarsh occurrence records.
• Developed the first global estimate of known saltmarsh extent.
• Created a Geographic Information Systems (GIS) polygon shapefile representing mapped saltmarsh areas.

Main Results:

• The dataset includes saltmarsh data from 99 countries.
• Mapped 5,495,089 hectares of saltmarsh across 43 countries and territories.
• The most extensive saltmarshes are located outside the tropics, particularly in the North Atlantic region.

Conclusions:

• This dataset represents the most comprehensive global compilation of saltmarsh occurrence and extent to date.
• While conservative in its mapping approach and acknowledging data gaps, the dataset covers many significant saltmarsh regions.
• The findings underscore the need for continued spatial data collection to fully capture global saltmarsh distribution and inform conservation strategies.