Why the relationship between water and agriculture needs to change
<p>One-fourth of the world's crops are grown in water-stressed zones. Here's a closer look at the tension between food and water.</p>
All living creatures need two things to survive: food and water. A WRI analysis shows just how much tension exists between those two essential resources.
A new interactive map from WRI’s Aqueduct project reveals that more than 25 percent of the world’s agriculture is grown in areas of high water stress. This figure doubles when looking at irrigated cropland, which produces 40 percent of global food supply.
This analysis highlights the tension between water availability and agricultural production. Finding a balance between these two critical resources will be essential, especially as the global population expands.
Agriculture under stress
Already, water demand in many parts of the world is meeting or exceeding natural supply. Overlaying global crop production maps with Aqueduct's Water Risk Atlas reveals agriculture’s current exposure to water stress.
In the face of this water-food nexus, three major points are important to keep in mind:
1. Different crops face different levels of stress in different regions. More than 40 percent of wheat is grown in areas facing high or extremely high levels of water stress. Fiber crops, such as cotton, are grown under even more stressed conditions. More than half of global cotton production happens in regions of high or extremely high stress.
2. Water consumption levels vary by crop type. Globally, roots (carrots and beets) and tubers (potatoes) require an average of 0.5 liters of water per calorie, whereas legumes (lentils and beans) require 1.2 liters per calorie, according to researchers at the University of Twente and the Water Footprint Network. In other words, different types of crops create different water footprints.
3. Irrigated land is twice as likely to be highly stressed. Irrigation alone -- which can use surface water, groundwater, or both -- can dramatically increase crop production. However, it is an enormous water consumer and the single-largest driver of water stress around the world. As ever-higher food demand drives more farmers to irrigate their land, the world’s rivers and aquifers will be increasingly strained.
These strained resources are a problem in themselves, but they also affect the ability of water users and managers to respond to droughts and other severe or chronic shortages. In areas where water is plentiful or where fewer users are competing, the excess supply acts as a buffer when droughts settle in. Droughts are more damaging in more arid areas or places where too many people compete for limited resources.
A growing risk
The tension between crop production and available water supply is already great, as agriculture currently accounts for more than 70 percent of all human water withdrawal. But the real problem is that this tension is poised to intensify. The 2030 Water Resources Group forecasts that under business-as-usual conditions, water demand will rise 50 percent by 2030. Water supplies, however, will not -- and physically cannot -- grow in parallel. Agriculture will drive nearly half of that additional demand, because global calorie production needs to increase 69 percent to feed 9.6 billion people by 2050.
The food-water tension won’t just be felt by agriculture, either. Agriculture’s growing thirst will squeeze water availability for municipal use, energy production and manufacturing. With increasing demand in all sectors, some regions of the world, such as northern China, are already scrambling to find enough water to run their economies.
Securing the future
Only by looking at food and water together is it possible to address the challenges within both. That is why WRI is working on mapping how the world’s relationship with water will be changing in the coming decades and identifying sustainable solutions to increase food production. For example, future food demand will only be met if farmers increase crop yields through better soil and water management. Furthermore, water use can be reduced through a suite of solutions like reducing food loss and waste, shifting to healthier diets, reducing biofuel demand and achieving replacement fertility rates.
These are just a few of the solutions that will be necessary if we are to ensure a water-secure and food-secure future. With better data on where and how agriculture is constrained by water, countries and companies can create a more robust agricultural sector without overtaxing water and other natural resources.