Oct 25, 2009

Biofuels May Still Pose Threat to Environment, Says Study

Biomass is a threat. Potentially. Or when it is grown on land which has been cleared of vegetation because it may leave a higher carbon footprint than previously thought. Biofuel crops that result from ‘displacement of crops’ may be twice as harmful in terms of CO2 emission as when biofuel crops are grown on dedicated pieces of land, a study led by Jerry Melillo from Marine Biological Laboratory reveals.

This is because the removal or displacement of pastures causes a sharp drop in CO2 absorption by plants, which counts as ‘carbon losses from indirect land use’ under the Kyoto Protocol accounting rules. Direct land-use emissions are generated when biomass is grown without reducing the land’s agriculture. Large amounts of greenhouse gasses that are released as a result of large biofuel programs are an ‘unintended consequence’ in both indirect and direct land-use, but the consequence is greater when clearing of forests is involved.

Greater use of fertilizer on this biofuel cropland may also contribute to greenhouse gas emission in the form of nitrous oxide (N2O), thus warming up the planet quicker than previously thought, the study noted. A model created by the scientists predicts that as the demand for biomass, and hence fertilizer increases in the future, N2O will contribute more than CO2 to rising temperatures.

Currently, no country or legislation counts the net effect of biomass crops that stem from changes in land-use, i.e. crop removal or displacement. Therefore, this study reveals a critical flaw in man’s recent attempt to limit fossil fuel emissions by aggressively shifting energy dependence to biofuels.

This simply compounds the recent flaws discovered in the Kyoto Protocol accounting rules, which fail to consider the net increase in greenhouse gasses as large firms begin to burn and cut down forests in order to grow biomass.

Source: Marine Biological Lab, Science Daily, iStockPhoto
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