Grain fields in sea-landscapes.

Sea-level rise will increase salt intrusion and flood risk in low-lying lands. In the long run, these lands will change into seawater-influenced landscapes, as is already happening in several coastal areas around the globe. While conventional agriculture may no longer bear fruit in such sea-landscapes, the seagrass species Zostera marina, "sea-rice," potentially yields 3-7% of global rice production, with the added benefit of zero-carbon emissions. Culture of Z. marina does not require freshwater, fertilizer or pesticides. Development and implementation of seagrass mariculture will open new avenues for collaborative efforts of multiple disciplines such as agronomy, coastal engineering and social sciences. From the start, the domestication, engineering design and landscape planning should aim at the optimal balance between ecosystem goods (grains, straw and seafood) and services (coastal protection, carbon and nitrogen sequestration, filtering of pathogens and pollutants, and biodiversity) of this potential crop, while respecting and restoring the wild meadows.