At the United Nations Conference on Climate Change in Cancun, Mexico, in December, the Director General of the Food and Agriculture Organization of the United Nations (FAO), Jacques Diouf, emphasized the need to promote what he called "climate smart" agriculture for food security and climate change adaptation. "By climate smart," he said, "we mean agriculture that sustainably increases productivity and resilience to environmental pressures, while at the same time reduces greenhouse gas (GHG) emissions or removes them from the atmosphere, because we cannot ignore the fact that agriculture is itself a large emitter of greenhouse gases."
Cross posted from the Worldwatch Institute's Nourishing the Planet
Diouf said that multiple climate smart agricultural practices were already widespread in the developing world, and he gave examples of practices—including crop diversification and urban farming—that could be replicated on the larger scale in the coming years. The FAO released a report just before the conference outlining some of those examples. Seaweed farming, for example, could help to mitigate GHGs while also supplementing incomes, providing dietary protein, and offering a sustainable source of biofuels.
Unlike many crops, seaweed farming does not require fertilizers, forest clearing, or heavy use of fuel burning machinery. As a result, production of seaweed does not significantly contribute to global GHG emissions.
Seaweed grows quickly and has a rapid rate of photosynthesis—the process that turns sunlight and carbon dioxide into plant energy and oxygen. This means that it absorbs carbon dioxide from the atmosphere more rapidly than most plants, making the crop even more ‘climate smart.’
Seaweed filters nutrients from coastal waters and could be cultivated in areas where agricultural runoff is in high concentration. Runoff of nitrogen fertilizers and manures from agriculture can become concentrated in some coastal areas. Filtration from seaweed crops could improve water quality and the abundance of fish in degraded coastal ecosystems.
In overfished coastal communities, seaweed farming offers an alternative source of income. The World Wildlife Fund (WWF) is helping fisher families supplement their incomes by farming seaweed in the Philippines. Overfishing and destructive fishing practices have depleted fish supplies and WWF is hoping to decrease dependence on fishing and reduce the pressure on coastal ecosystems through seaweed cultivation.
According to a 2009 FAO report, an algae-based biofuels industry could create jobs and energy independence in tropical developing countries with coastal environments. Seaweed is a type of algae—or macro-algae—and can be converted to biodiesel. Algae have a high oil content, and the oil can be converted into fuel using the same process that is used for vegetable oils. Unlike land-based biofuel crops, seaweed does not compete for land and water resources with food crops. According to the Natural Resources Defense Council, biofuels from seaweed hold a lot of potential as a clean-burning renewable energy source.
Seaweed is highly nutritious and can have a protein content of up to 50 percent. It has been eaten traditionally for thousands of years in East Asia and is gaining popularity in other parts of the world. It is often used in soups, sushi, and salads.
Seaweed can also be used as animal feed and is sometimes added to salt to increase the iodine content. China produces far more seaweed as a crop than any other country—about 5 million tons annually—followed by South Korea and Japan. Production is spreading, however, to places like Indonesia and Zanzibar in Tanzania. Demand for seaweed has far exceeded easily accessible natural supplies, and seaweed farming is a rapidly expanding industry. Commercial cultivation is now taking place in about 35 countries, and it is estimated to be a $6 billion industry.
Seaweed is traditionally cultivated by tying the plants to suspended lines or ropes supported by poles at each end in shallow water. Floating rafts can also be used in deeper water. Seaweed grown in deeper water grows faster, but it is more difficult to build the required structures and to harvest. The crop is dried in the sun after harvesting for transport to markets.
Agriculture will certainly take on innovative new forms in the coming decades as farmers and policy makers adapt to mounting population and climate pressures. "We will not achieve food security without serious investment in climate change adaptation," declared Diouf in Cancun. As sea levels rise and farmland becomes degraded and more scarce, it may be time to take farming to the sea.