Agriculture and Environment in a Crowding and Warming World

Of the world's land area and soils, only some 25% can be regarded as suitable for agriculture, the remainder having soils that are too dry or too wet, steep, rocky, cold, shallow, acidic, alkaline, or saline to permit the growing of crops. The actual arable land under cultivation (some 12%) is less than half of the potentially cultivable area, with an additional quarter used for grazing livestock (including areas of prairie, savanna, and scrub vegetation) (Hillel, 2008). However, any substantial expansion of cultivation would pose a severe threat to the remaining natural ecosystems and their biodiversity. Hence, to meet the requirements for food security, there is a need to intensify production and to do so sustainably—that is to say, without degrading the resource base of soil, water, and energy. This must be done without changing the climate for the worse, while adapting to its projected changes through the coming decades (Beddington et al., 2011; Hillel, 2009)…