Water is essential for food production, and agriculture accounts for about 70 percent of the world's fresh water consumption. As countries increase agricultural production (by 2050, FAO estimates that approximately 9,7 billion people will need to feed), irrigated land will need to increase by more than 50%. However, climate change is already reducing the supply of water available for crops in some regions.
To help farmers cope with this problem, the International Potato Center (CIP) is exploring ways to improve irrigation. Recent research by scientists and students from the CIP and the National Agrarian University of La Molina in Peru has confirmed that images from infrared (thermographic) cameras can be used to detect water stress in crops and thus use water more efficiently.
A group of researchers led by CIP scientist David Ramirez conducted a series of experiments near the city of Lima (Peru) to determine how a combination of color and infrared images could be used to monitor water stress of potato plants.
The researchers photographed the potato field during the day and used open source CIP software called the Thermal Image Processor (TIPCIP) to determine when the plants were warm enough to be watered. By irrigating only when plants reached this threshold, the researchers were able to significantly reduce the amount of water used for irrigation.
“The goal was to determine the minimum amount of water needed for potatoes to get a good harvest,” Ramirez said.
“The combination of monitoring and drip irrigation can enable farmers to reduce the amount of water needed to grow potatoes by at least 1600 cubic meters per hectare, which is about half the amount of water used in traditional surface irrigation,” he explained.
The combination of optimal water management and the introduction of drought tolerant varieties could significantly increase the water resistance of potatoes and allow them to be grown in regions where there is currently little or no food, or during dry months when agricultural land is fallow.
Ramirez explained that while infrared cameras can be installed on drones to monitor water stress on large farms, the cost of such equipment is prohibitive for small and medium-sized farmers. Thus, he plans to test a new option - a plug-in device that turns a smartphone into an infrared camera and costs about $ 200. CIP scientists have recently developed a new, more user-friendly version of TIPCIP for smartphones and are planning a future version that will provide more specific information on when and how much water is needed.
“By using open access technology, we can help farmers produce food with less water,” Ramirez confirmed.
However, he added, such technology must be complemented by a greater awareness of the importance of sustainable water management.
This study was supported by the World Bank through the National Innovation Agrarian Program (PNIA) and the CGIAR research program.