By Kim Robson:
Food and water, two of man’s four necessities for survival, are inextricably connected. When the growing global demand for higher food yields stresses available water resources, both are in jeopardy. At the World Resources Institute (WRI), new analysis shows that more than 25 percent of the world’s agriculture is undertaken in areas of high water stress. More than 50 percent of irrigated cropland, which produces 40 percent of our global food supply, exists in areas of extremely high water stress.
Water stress is defined as the total ratio of water supply withdrawals to available renewable water supply in an area. In high risk areas, 40 percent or more of the available supply is withdrawn every year. In extremely high risk areas, withdrawals can be up to 80 percent or higher. A higher percentage means more users are competing for limited water supplies.
A new interactive map from WRI’s Aqueduct project reveals precisely how and where tension exists between these two essential resources — food and agriculture. Different crops affect different areas: click on a crop on the left sidebar to view a world map with color-coded areas of highest water stress. More than 40 percent of wheat and 50 percent of cotton is grown in areas facing high or extremely high levels of water stress. Rice also uses a tremendous amount of water. Use your scroll wheel or the navigation buttons at the upper left of the map to zoom in for more detail.
Finding a balance between the need for high agricultural yields and renewable water supplies will be essential as the world’s population grows. Currently, agriculture accounts for more than 70 percent of all human water use. The 2030 Water Resources Group forecasts that if we continue as we are, water demand will increase by 50 percent by the year 2030. Water supplies, however, will not – and cannot – increase. Agriculture is expected to account for more half of that additional demand, as global calorie production needs to increase 69 percent to feed 10 billion people by 2050.
A few concerns to note:
· Different types of crops consume varying levels of water. According to researchers at the University of Twente and the Water Footprint Network, root crops like carrots, beets and potatoes need an average of 0.5 liters of water per calorie; but legumes like peanuts, lentils and beans require 1.2 liters per calorie.
· Irrigated cropland is much more likely to be highly stressed. Irrigation alone, whether from surface water, groundwater, or both, can dramatically increase crop yields, but also creates the single largest water stressor in the world. As ever-increasing demand drives more farmers to irrigate their crops, water supplies will be increasingly strained.
· The growing demands of agriculture will take priority over water made available for private and municipal use, energy production and manufacturing. With increasing demand in all of these sectors, some regions such as northern China are already facing critical shortages of clean water supplies necessary to run their economies.
WRI is attempting to map how the world’s relationship with water will change with demand in the coming decades and identify sustainable solutions for increasing food production. Demand for food supplies in the future will be met only if farmers increase crop yields through better soil and water management, not through the use of GMOs. Water can be conserved by reducing food loss and waste, shifting to healthier diets and organic farming, reducing biofuel demand, and other methods. With better information on where and how agriculture affects water supplies, countries and companies alike can grow the agricultural sector without overtaxing water and other natural resources.