Protected forests in developing nations are losing large numbers of trees and creating significant carbon emissions, despite their special status.
Safeguarded areas worldwide are being exploited rather than saved for conservation, a study shows.
Incentives for exploitation – such as illegal logging, agriculture and palm oil plantation – are outweighing the benefits of protection, researchers say.
The University of Edinburgh study found that intervention is needed in these areas to combat their disproportionate carbon emissions.
The study, published in Scientific Reports, outlines that deforestation rates are slowing in Brazil, but increasing throughout South East Asia.
Indonesia is the second largest source of gross emissions from protected areas, after Brazil.
Indonesia produces disproportionately more emissions from its protected areas than any other country.
Indonesia's protected areas total only 15 per cent of Brazil's comparative areas but produce emissions equivalent to 25 per cent of those from Brazil.
This is despite Indonesia accepting $1bn from Norway to reduce deforestation over a seven-year period.
Cambodia has lost 16.5 per cent of its protected forest carbon in only 12 years. Over the same period, significant loss in protected forest areas occurred in Guatemala (9.4 per cent); Mozambique (8.1 per cent); Côte D'Ivoire (8.0 per cent) and Grenada (6.7 per cent).
More than a quarter – 27.3 per cent – of all emissions from the world's protected areas are produced by only 1.1 per cent of these forests.
Forest loss accounts for approximately 18 per cent of the world's carbon emissions, researchers say. The loss increases atmospheric greenhouse gas, changes the global climate and reduces the availability of the Earth's carbon sinks – anything that absorbs more carbon that it releases as carbon dioxide.
Carbon emissions increase when trees are burnt and cleared from land, releasing harmful levels of carbon dioxide into the atmosphere.
Researchers hope the study may inform conservation strategies to limit the risk to protected forests.
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