Farmers living on degraded land are excluded from the benefits of economic growth in many developing countries, research suggests.

A paper, published in PLOS One last week (11 May), found that the ability of economic expansion to reduce a country’s overall poverty falls significantly as the proportion of the rural population living on degraded agricultural land rises.

The researchers estimate that the number of people living on degraded agricultural land grew by 12.4 per cent between 2000 and 2010 to roughly 1.5 billion people — of whom 1.4 billion live in the developing world.

“These areas are pockets of poverty,” says joint lead author Edward Barbier, an economist at the University of Wyoming in the United States. “These people don’t have the money or assets to invest in improving their land, so the problem continues.”

For their study, the researchers compared satellite data on farmland productivity, rural population distribution and changes in income growth and poverty levels between 2000 and 2012 from 83 developing countries.

The paper explains that living on degraded land limits harvests and profits for farming families, negating the benefits brought about by general economic growth, such as better market access and investments in modern farming practices.

The team did not examine why a growing number of people work on degraded agricultural land, Barbier says. But he suspects that the best farmland is being increasingly dominated by large-scale commercial agriculture, pushing poor people onto cheaper, lower quality land.

However, Ephraim Nkonya, a land management researcher at the International Food Policy Research Institute, warns that land degradation also affects high-income countries, where growing fertiliser use hides the problem.

“The impact of land degradation is much more severe on people who don’t have the resources to mask it,” he said. “But it’s a global problem, not just a developing world problem.”

Run-down agricultural land can be salvaged by measures such as soil improvement, diversified planting and better irrigation. The paper found that if more people live on improving land it magnifies a country’s ability to reduce poverty through economic growth.

For example, case studies from the Economics of Land Degradation Initiative, which funded the research, show that rotational grazing restored degraded rangelands and increased herders’ profits in Jordan.

But in areas where degraded land is beyond improvement, it may make sense to encourage farmers to seek opportunities elsewhere, says Barbier.