“Do we have to accept deforestation to feed the world?”

That was one of the provocative questions that Stanford Woods Institute Senior Fellow and land use expert Eric Lambin posed during a recent presentation of research with far-reaching implications for policymakers, businesses and consumers. Among the findings Lambin discussed with Stanford students and faculty during a Stanford Department of Environmental Earth System Science seminar: There is much less potentially available cropland (PAC) globally than previous estimates have suggested. Perhaps surprisingly, however, we don’t need to clear more land, including forests, to plant hunger-alleviating crops, Lambin said.

Previous PAC estimates by international organizations such as the World Bank have been consistently too high, according to Lambin giving decision-makers “carte blanche” to approve a variety of uses for large tracts of land.

By 2030, the additional land worldwide that will be needed for urban expansion, tree plantations and biofuel crops will equal the additional land that will likely be devoted to food crops, according to Lambin. This rapid transformation of the face of the planet makes it essential to get a handle on realistic PAC estimates. To do so, Lambin took a “bottom-up approach” that incorporated factors such as soil quality, land use restrictions, labor availability and occupation by smallholders. Lambin also considered trade-offs such as the carbon stocks lost and natural habitat destroyed by land conversion.

Lambin’s resulting PAC estimates in regions ranging from Argentina to Russia are, on average, only a third of other generally accepted estimates. Along the way, Lambin discovered some surprises. For example, what initially looked like good news – the fact that some countries have gone from net deforestation to net reforestation in recent years – turned out to be less hopeful. Lambin found that most countries in the developed and developing worlds that have stopped cutting down their forests have increased their imports of timber and wood products, often from tropical countries. This “outsourcing of deforestation” is one of several troubling global land trends.

On the other hand, Lambin pointed out that production of crops essential to alleviating hunger have increased in recent years, but their overall land use has not, due to more efficient and intensive agricultural methods. This net gain contradicts assertions that more land, including forests, needs to be cleared for farming in order to alleviate hunger, he said.

The real culprit for such land conversion, according to Lambin, is growing adoption of a Western diet heavy with meat, sugar and vegetable oils. Deforestation for agriculture is often driven by multinational companies that cultivate in tropical regions to export fatty and oily food products to urban markets in rich countries and emerging economies. These companies control a majority of global food supply chains and, in turn, local land use decisions. “Globalization has reshaped land governance,” Lambin said.

Globalization is not a bogeyman, though. In fact, Lambin said, it can be an engine for progress on these issues by allowing for new forms of market-based governance that effectively promote sustainable land use. Market mechanisms such as eco-certification labels and nongovernmental campaigns can promote and incentivize responsible land use, he noted, pointing to coffee farmers he studied with School of Earth Sciences Research Associate Ximena Rueda. The farmers increased tree cover on their plantations with the extra profit they reaped from eco-certified beans.