Modern irrigation systems boost carbon emissions

Environmental Research Web: As water scarcity increases in the Mediterranean, there is pressure on the agriculture industry to reduce water losses, improve efficiency and boost water productivity. In recent years, government-subsidized pressurized irrigation systems have replaced traditional low-efficiency surface irrigation schemes in many countries, in an attempt to minimize water losses and improve efficiency.

But researchers are warning that, despite making water savings, these modern irrigation systems are increasing the food-production system's contribution to climate change.

"These pressurized irrigation systems use more energy and therefore have higher carbon emissions than traditional gravity-operated systems," said Andre Daccache, from Cranfield University, UK. "We have carried out the first large-scale assessment of agricultural water demand in the Mediterranean region and estimated the carbon-dioxide emissions associated with water abstraction for irrigation."

...The calculations also revealed that Spain, which is becoming more reliant on groundwater and on pressurized systems to irrigate crops, uses three times the energy of Egypt, a country that almost exclusively employs water from the River Nile and is still largely dependent on traditional gravity-fed systems.

"While Spain is saving water with these new irrigation systems, it is clear that its carbon-dioxide emissions will be higher," said Daccache. "We were expecting to see a difference in energy use between countries but we were surprised by the size of the difference. The problem is that Spain with a dry climate and scarce surface-water resources does not have many options when it comes to irrigation technologies."...

An irrigation sprinkler in Adaja, Spain, shot by David A. Nafria, Wikimedida Commons, under the Creative Commons Attribution Share-Alike 3.0 Unported license