World Environment Day: effective ecosystems vital to cut greenhouse gas emissions

Boosting investments in the conservation, rehabilitation and management of the earth's forests, peat lands, soils and other key ecosystems could deliver significant cuts in greenhouse gas emissions and avoid even more being released to the atmosphere, said a new report by the United Nations Environment Programme (UNEP).
The UNEP's rapid assessment report, "The natural fix? The role of ecosystems in climate mitigation," is released to mark World Environment Day 2009, disclosed sources here on Friday.
The report says the adoption of a comprehensive policy framework under the UN Framework Convention on Climate Change (UNFCCC) for addressing ecosystem carbon management will be a very significant advance.
According to it, it is vital to manage carbon in biological systems, to safeguard existing stores of carbon, to reduce emissions and to maximise the potential of natural and agricultural areas for removing carbon from the atmosphere.
The priority systems are tropical forests, peatlands and agriculture. Reducing deforestation rates by 50 percent by 2050 and then maintaining them at this level until 2100 would avoid the direct release of up to 50 Gt C (measurement for carbon dioxide) this century, equivalent to 12 percent of the emissions reductions needed to keep atmospheric concentrations of carbon dioxide below 450ppm.
"Peatland degradation contributes up to 0.8 Gt C a year, much of which could be avoided through restoration. The agricultural sector could be broadly carbon neutral by 2030, equal to 6 Gt of CO2 equivalent or up to 2 Gt of carbon if sustainable management practices were widely adopted.
It is essential that climate mitigation policy is guided by the best available science concerning ecosystem carbon, and decisions should be informed by the overall costs and benefits of carbon management, it observed.
The report says developing policies to achieve these ends is a challenge: it will be necessary to ensure that local and indigenous peoples are not disadvantaged and to consider the potential for achieving co-benefits for biodiversity and ecosystem services. Drylands, in particular, offer opportunities for combining carbon management and land restoration, it says.
According to the report, recent estimates indicate that human activities are currently responsible for global carbon emissions of around 10Gt. The research indicates that there may be scope for tackling 15 percent of these, perhaps even more, through managing land use changes and carbon in ecosystems. "Forests, the largest sink tropical forests, hold the largest terrestrial carbon store with an annual global uptake of around 1.3 Gt of carbon, or about 15 percent of the total carbon emissions resulting from human activities.
Global tropical deforestation rates are currently estimated to be as high as 14.8 million hectares per year (about the size of Bangladesh), while deforestation is responsible for nearly one-fifth of the global greenhouse gas emissions, more than the entire transport sector.
Clearing of tropical forests may release an additional 87 to 130 Gt by 2100, corresponding to the carbon release of more than a decade of global fossil fuel combustion at current rates. Reducing deforestation rates by 50 percent by 2050 and then maintaining them at this level until 2100 would avoid the direct release of up to 50 Gt of carbon this century, it added.
According to it, the agricultural sector has the largest readily achievable gains in carbon storage if best management practices, such as avoiding turning over the soil and using natural nutrients like compost and manure, were widely adopted. Up to 6 Gt of CO2 equivalent, or up to 2 Gt of carbon, could be sequestered each year by 2030, which is comparable to the current emissions from the agricultural sector. Many of the agricultural practices that store more carbon can be implemented at little or no cost. The majority of this potential (70 percent) can be realised in developing countries.