As sea levels rise and coastal landscapes shift, a new climate-resilient crop is gaining attention: seagrass grain. Environmental scientist Marieke van Katwijk proposes an innovative solution—cultivating seagrass for bread-making in the transforming coastal zones of the future.
Rising Sea Levels Open the Door to Seagrass Farming
With global sea levels predicted to rise significantly over the next century, more low-lying lands will be influenced by seawater. While some coastal flooding can be prevented or delayed, in many regions, saline waters will inevitably shape the landscape.
Van Katwijk, writing in the scientific journal Ambio, argues that these emerging sea-landscapes can be used productively to grow seagrass species like Zostera marina, whose seeds can be harvested for human consumption.
Seagrass Seeds: Nutritious and Ancient
The concept isn’t new. For centuries, communities in Mexico have used seagrass seeds to make bread, a tradition that showcases the plant’s nutritional and culinary value. In some regions, the natural yield of seagrass grains is already comparable to rice, making it a promising alternative food source.
Van Katwijk explains that countries like the Netherlands are especially suited for developing seagrass grain farming, thanks to their advanced knowledge in coastal engineering and seed breeding technologies.
Environmental Benefits of Seagrass Cultivation
One of the most compelling advantages of seagrass farming is its eco-friendliness:
- No need for artificial fertilizers or pesticides
- No freshwater usage
- Zero CO₂ emissions
- Carbon sequestration: Seagrass stores carbon in the seabed
- Water purification and improvement of coastal water quality
- Creation of a biodiverse marine habitat, supporting fish and invertebrates
Even the detached leaves after harvest can be repurposed for insulation materials, adding to its environmental value.
A Delicate Balance: Cultivation vs. Conservation
However, van Katwijk emphasizes that seagrass cultivation must not compromise wild ecosystems. While wild seagrass meadows have significantly declined—especially in the Netherlands—restoration efforts are underway. Cultivation techniques could support conservation by producing wild varieties for rewilding and restoration programs.
Challenges and Opportunities Ahead
Despite the promising outlook, several challenges must be addressed:
- Low global seed production rates
- Lack of large-scale cultivation techniques
- Need for new investment models and regulatory frameworks
Still, research in the Netherlands and other coastal nations is progressing, and van Katwijk urges policymakers and scientists to act now. “We must begin shaping the future of sustainable ocean farming,” she states.
A Tasty Future: Bread Made from the Sea
What about the taste? According to van Katwijk, bread made from Zostera marina seeds is said to have a flavor similar to rye, with excellent nutritional value, making it an exciting new sustainable food product for future generations.
Reference:
Marieke M. van Katwijk (2025). Grain fields in sea-landscapes. Ambio. DOI: 10.1007/s13280-025-02191-z
Provided by:
Radboud University