ABSTRACT
The world’s net cultivated area has grown by 12 percent over the last 50 years, mostly at the expense of forest, wetland and grassland habitats. At the same time, the global irrigated area has doubled. The distribution of these land and water assets is unequal among countries. Although only a small proportion of the world’s land and water is used for crop production, most of the easily accessible and (thus economic) resources are under cultivation or have other ecologically and economically valuable uses. Thus the scope for further expansion of cultivated land is limited. Only parts of South America and sub-Saharan Africa still offer scope for some expansion. At the same time, competition for water resources has also been growing to the extent that today more than 40 percent of the world’s rural population is now living in water-scarce regions.
