DAKAR (AlertNet) - West African farmers could have saved 2.1 million hectares of tropical forest from being cleared or degraded if they used more fertiliser to grow crops such as cocoa, cassava and oil palm, according to a study by the International Institute for Tropical Agriculture.
About two million households in West Africa depend on cocoa for their income. Between 1997 and 2007, production of the crop doubled in the region's Guinean Rainforest area, which stretches from Liberia to Cameroon.
Forest with high potential for reducing carbon emissions, was cleared for agriculture, and by the start of the new millennium, the Guinean Rainforest covered a mere 113,000 sq km or 18 percent of its original area, the report said.
James Gockwoski, one of the authors of the study, said farmers employing traditional agricultural techniques such as slash-and-burn and land clearing used three hectares to produce one tonne of cocoa per year, whereas if they had used fertilisers, it would have taken them only one hectare to produce the same amount.
"What we're arguing is that if we had increased the yield in the past we wouldn't be quite where we are today. We would have had less land in production and more land in forest," Gockwoski told AlertNet by telephone from Accra, Ghana.
Farmers in poor countries favour burning land because the ash that is left in the soil contains nutrients to feed crops. However, nutrients can become depleted or washed away over time leading farmers to clear and burn more land.
Deforestation and forest degradation through the clearing land to grow crops, build roads and other infrastructure or to use for grazing as well as logging and fires account for nearly 20 percent of global greenhouse gas emissions -- more than the entire global transportation sector and second only to the energy sector, according to the United Nations.
Gockwoski said nearly 2 gigatonnes of CO2 had been emitted into the atmosphere as a result of the deforestation of about 80 percent of the Guinean Rainforest. One gigatonne is equivalent to one billion tonnes.
"What's happened over the years is that the forest has virtually been used as a fertilizer bank that has now just had the entire principal drawn down and what's left needs to be conserved," he added.
The IITA researchers believe policy makers and climate negotiators involved in talks on REDD, or Reducing Emissions from Deforestation and Forest Degradation, should factor this into their discussions and consider using REDD funds to offer incentives for using methods that would increase agricultural yields.
REDD is a UN-backed effort under which richer greenhouse gas emitting countries pay poorer tropical forest countries to protect standing forest as a way of curbing carbon levels in the atmosphere.
"Scattered across the (West African) region we have some significant forest reserves that have been almost completely encircled by smallholder farmers looking to expand their production," Gockwoski said.
"If we can't offer them more land we need to offer them technologies that they can substitute for more land and that means sustainable intensification," he added.