Article // Role of Soils for Satisfying Global Demands for Food, Water, and Bioenergy

By Winfried E. H. Blum. — The large increase in food production in the second half of the last century, mainly through the “green revolution” and further positive developments, especially the use of fertilizers and plant protection products, could not prevent the situation that today nearly one billion people live with hunger, mostly because of lack of access to food. In total, about four billion people can be considered malnourished, due to further specific nutritive deficiencies. The sustainable production and availability of food is also increasingly threatened by impacts deriving from human activities, especially changing forms of land use at local and global scales. Most critical are soil losses through sealing by urbanization, industrialization, and transport, probably the most important threat to food security at all, but also erosion by water and wind and further severe forms of soil degradation, such as loss of organic matter, contamination, loss of soil biodiversity, compaction, salinization, nutrient mining, desertification, and flooding, endanger food security. Climate change as well is threatening food security directly with increasing losses and degradation of soil, mainly through extreme events. In many regions, a decrease of freshwater resources is threatening rain-fed and irrigation agriculture. Meanwhile, there is a serious competition for space, energy, and water emerging from biofuel production and a concomitant increase in demand for food and fiber on local and world food markets.