Deforestation is being tackled internationally by the United Nations Framework Convention on Climate Change (UNFCCC), through the Reducing Emissions from Deforestation and Degradation (REDD) programme. REDD seeks to give financial incentives to developing countries to reduce deforestation and forest degradation – the latter is essentially the thinning out of forests during processes such as selective logging. Meanwhile REDD's offshoot programme, REDD+, seeks to deliver other benefits, such as biodiversity conservation.

In designing a system for REDD, it is important to understand what is driving deforestation and forest degradation. Deforestation driven by commercial agriculture, for example, would require a different mitigation strategy to deforestation driven by local, subsistence agriculture. But while drivers have been studied on a regional level, little data exists on a national level.

Now, Martin Herold and Veronique De Sy at Wageningen University in the Netherlands, together with colleagues in Japan, the US and Indonesia, have produced what they say is the most up to date and comprehensive overview of drivers on a national level. Their assessment is based on the synthesis of driver data from various sources, including empirical data reported by developing countries, the Centre for International Forestry Research, the UNFCCC and scientific literature.

All developed countries have followed the same phases of deforestation: their forests start out widespread, then they decline rapidly to make way for agriculture, and finally they slowly restock. Herold, De Sy and colleagues considered 100 developing countries, and categorized them as being in one of these phases, based on forest cover and the rate of forest-cover change. Having analysed the driver data, the researchers sorted the countries according to the drivers that were most relevant.

The team found that the drivers for deforestation were similar in Africa and Asia, while degradation drivers were similar in Asia and Latin America. Deforestation was mostly driven by commercial agriculture, followed by subsistence agriculture. Degradation, on the other hand, was mostly driven by timber extraction and logging, followed by fuel-wood collection and charcoal production.

Martin believes the most interesting result is the regional difference in the importance of commercial versus subsistence agriculture. "In the past, the general thinking was that rural populations and their agricultural activities were a main driver, but it is clear that this has changed to a dominance of commercial, globalized agriculture, especially in Latin America," he said. "In Africa this is not the case, but this is expected to change."

The next step, said Martin, is to "fill in the data and knowledge gaps" so that they can see the drivers that are underlying the broad ones outlined in his group's assessment. Also, he added, they would like to examine how countries can monitor the drivers to formulate national policies and strategies.

The study is published in Environmental Research Letters (ERL).