David Burton, a soil scientist and professor at Dalhousie University in Halifax, said that over the years, intensive agriculture production methods — particularly tillage, which breaks up the soil in preparation for planting — have dramatically reduced the amount of organic matter in the soil.

The result of less organic matter is that “the soil structure is being degraded, such that soils have difficulty holding water and resisting soil erosion, and they become less fertile,” Burton said.

“That’s making our agricultural production systems less and less productive, and some soils are becoming deserts and no longer able to produce food.”

“Unless we improve our soil and soil management, we only have 60 harvests left,” Burton said, referring to the UN’s statement. “We’ll only have 60 years to produce the food to support the world’s population.”