The paper's authors argue that, with more than 800m people chronically hungry: "The use of highly productive croplands to produce animal feed is questionable on moral grounds because this contributes to exhausting the world's food supply".
After the dissolution of the Soviet Union and subsequent cessation of the state subsidies for collective agriculture, large areas of less productive croplands were either abandoned (Alcantara et al. 2012, 2013; Prishchepov et al. 2012) or the fallow periods increased (de Beurs and Ioffe 2014).
It measures the requirements for productive areas (croplands, grazing lands for animal products, forested areas to produce wood products, marine areas for fisheries, built-up land for housing and infrastructure, and forested land needed to absorb carbon dioxide emissions from energy consumption).
The United States, blessed with a vast area of highly productive rain-fed cropland, is the world's biggest exporter of virtual water, sending millions of tons of grain to countries around the world.
Less than an hour's drive outside Havana are Cuba's most productive pastures and croplands, but the country still needs to import about 80% of its food.
The restoration of severely degraded cropland to productive agricultural capacity increases food supply, improves soil and water conservation, and enhances environmental and ecological services.
Production on rainfed cropland is limited by water produced directly on the cropland and cannot be maintained by irrigation.
