The authors of a new report released in Nairobi say that agricultural practices need not drive deforestation worldwide, but can instead be used to replenish the world's diminishing trees. The study used satellite imagery to find that nearly half of the world's crop lands also contain what it deemed as "significant" tree cover.

The satellite images show nearly half of farmlands across the world are covered at least 10 percent by trees. Farmers use the trees for a variety of purposes, including as secondary cash crops, windbreaks, animal feed, timber, fertilizer, and shade.

The report was released this week at the World Congress on Agroforestry meeting in Nairobi, Kenya.

The director general of the World Agroforestry Center who authored the report, Dennis Garrity, says the study was the first of its kind and revealed more tree cover in farmlands than previously thought.

"We had never been able to do a complete satellite coverage analysis of the aerial extent of trees on farmlands throughout the world," he said. "Now that we have that data we were pleasantly surprised to find that somewhere one-half of the farmland in the entire world has significant to dense tree coverage on it."

While the 10 percent figure may not seem significant, the authors say that in fields designated primarily for crop growth, that percentage is actually quite high.

The World Agroforestry Center hopes the new information will spur policy makers to find ways to encourage the further integration of trees into agricultural landscapes. The world's diminishing tree cover is curtailing the earth's ability to capture carbon and slow the effects of global climate change.

According to Garrity, the findings are especially relevant for explaining how the world economy could still produce vital natural resources if deforestation was ever successfully halted.

"Imagine for a moment that the world could actually stop deforestation," he said. "That would mean that the we would have to stop taking timber out of the forests and many other products. Where would those products come from? They would have to be grown on farms, outside the forest. And that is the transformation that is actually occurring in many countries, but it is unrecognized, and it is certainly unappreciated."

The organization hopes next to follow up on its report with a more in-depth study that details precisely how each region's farmers use the trees to supplement their agricultural practices.

The authors of the study claim that additional investment in agroforestry could rid the atmosphere of 50 billion tons of carbon during the next 50 years.

The study reported the only regions in the world for which trees are not an integral part of agricultural land were North Africa and West Asia.