Forests are necessary for the survival of billions of people who rely on them, argues a new UN report presented in Rome Monday.

"Food from the forests -- like fruit, nuts, mushrooms, leaves, roots, insects and wild animals -- often contributes a nutritious supplement to rural people and provides a safety net in times of hardship," said Eva Mueller, director of the Food and Agriculture Organization's Forestry Division.

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Mueller was commenting on the UN's State of the World's Forest report, which argues that it's time to shift conservation efforts from "trees to people."

Forests employ 13.2 million people in the formal forestry sector, the report said. Nearly a third of the world's population requires wood for cooking, and 764 million people use wood as fuel to boil drinking water.

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Mueller estimated forests provide the habitat for about 80 percent of the world's biodiversity and are "home to many pollinator species."

Hat tip: BBC News. Photo: Thinkstock