Mapping where a country's carbon stocks overlap with areas that are rich in wildlife and important for local peoples' livelihoods is underway in Asia, Africa and Latin America.

The aim is to support international efforts to conserve forests in order to combat climate change. But in a way that delivers other benefits including conservation of economically-important ecosystems linked with water, fertile soils and other crucial services.

Under the UN Framework Convention on Climate Change (UNFCCC), governments are negotiating a mechanism to provide payments for Reduced Emissions from Deforestation and forest Degradation plus additional forest "activities" (REDD+), with the aim of halving deforestation by 2020.

It is estimated that currently close to 18% of greenhouse gas emissions-equivalent to around six Gigatonnes (Gt) of C02- are linked with land use change, mainly through forest loss. In 2004, this amounted to more greenhouse gas emissions than those of the transport sector.

The maps, being compiled by a partnership led by the UN Environment Programme's World Conservation Monitoring Centre (UNEP-WCMC), are overlaying the carbon held in the vegetation and soils of a country's terrestrial ecosystems with other key features.

These include population densities; economic activities such as honey and gum production; the location of existing Protected Areas and biodiversity.

Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said: "The aim is to assist governments in setting priorities for carbon investments. In Tanzania for example, several carbon rich parts of the country are in areas where the ranges of almost 70% of the country's mammal species overlap".

"The mapping also reveals that almost a quarter of Tanzania's total carbon stocks are in high carbon density areas that are not formally protected. This is the kind of science and analysis that governments from Ecuador to Cambodia are also now looking at to maximize the benefits of investments in REDD+ and accelerate a transition to a low carbon, resource efficient Green Economy," he added.