From the Aral Sea basin in central Asia to the San Joaquin Valley of California, 20 percent of the world’s irrigated land is degraded by salt buildup, says a study by United Nations University. “Today an area the size of France is affected,” says a UNU statement. The economic impact of crops losses due to salt is $27.3 billion. The researchers say the lands should be restored as a way to meet food demands of a rising world population.
“Among methods successfully used to facilitate drainage and reverse soil degradation: Tree planting, deep plowing, cultivation of salt-tolerant varieties of crops, mixing harvested plant residues into topsoil, and digging a drain or deep ditch around the salt-affected land,” says UNU.
In an essay in the journal Trends in Plant Sciences, researchers suggest that breeding salt-tolerant crops is a way to boost food production. “We suggest that we should learn from nature and do what halophytes, or naturally salt-loving plants, are doing: taking up salt but depositing it in a safe place—external balloon-like structures called salt bladders,” says co-author Sergey Shabala of the University of Tasmania, in Australia, according to the site phys.org. Shabala and colleagues suggest wheat or rice could be modified to develop salt bladders while maintaining yields.