Uncovering carbon and biodiversity clues in Cádiz Bay

Earlier this month, the REWRITE team kicked off its first full field campaign in Cádiz Bay, Spain, one of the demonstration sites where we’re testing nature-based restoration approaches across Europe. These demonstration sites are the backbone of our project: living laboratories where we explore how rewilding can help restore coastal and estuarine ecosystems and enhance their ability to adapt to climate change. Discover them all here.

Cádiz Bay: natural, abandoned, and accidentally rewilded

From 9 to 13 June, researchers and partners conducted an intensive field session across three representative locations:

• Isla Verde, a naturally functioning but logistically complex site

• Santa Isabela, an area abandoned by former human activities

• Santa Gertrudis, an example of accidental rewilding

Each location offers a unique perspective on how coastal areas evolve when left to nature or when guided by minimal intervention.

What we did in the field

Throughout the week, the team carried out a wide range of activities to capture both the carbon dynamics and biodiversity patterns of these saltmarsh and mudflat ecosystems, including:

• CO₂ flux measurements using benthic chambers to estimate gas exchanges between sediment and atmosphere
• Sediment coring to evaluate blue carbon storage potential
• Biogeochemical incubations and microelectrode profiling in the lab to assess nutrient cycling
• eDNA sampling to uncover hidden microbial communities and biodiversity indicators
• Stable isotope analysis to trace food web connections
• Hyperspectral and multispectral imaging, both handheld and drone-based, to enable large-scale habitat mapping
• Vegetation surveys to evaluate saltmarsh structure and functioning

These data-rich activities will help us better understand how these habitats store carbon, support biodiversity, and interact with environmental pressures.

What’s next: from Spain to Portugal and Belgium

The field season has only just begun. Over the coming month, REWRITE researchers will continue gathering critical data in two other demonstration sites:

• Ria de Aveiro (Portugal) – a coastal lagoon with a complex mix of natural and human-modified areas

• Scheldt Estuary (Belgium) – where human infrastructure and estuarine dynamics intersect in unique ways

These upcoming campaigns will allow us to compare restoration pathways and ecosystem responses across different contexts, strengthening our understanding of how rewilding can deliver climate and biodiversity benefits at scale.

Stay tuned as the season unfolds, and follow REWRITE’s journey into Europe’s coastal rewilding frontiers.

📍 More updates coming soon from the field!