Africa alone holds over 33 percent of the total available land in all the scenarios.

Biofuel crops can potentially meet half of the current global demand for fuel without affecting food crop production, according to researchers at the University of Illinois.

Ximing Cai, a professor of civil and environmental engineering at the university, led a team of researchers in isolating land areas across the globe suitable for producing biofuel grass crops with minimal agricultural or environmental impact.

“The questions we’re trying to address are, what kind of land could be used for biofuel crops? If we have land, where is it, and what is the current land cover?” said Mr. Cai.

The research team determined land availability by evaluating physical characteristics such as soil properties, soil quality, land slope and regional climate. The researchers collated data on soil, topography, climate and current land use from data sources such as remote sensing maps.

The researchers limited the study to consider only abandoned or degraded lands, areas unfit for agricultural purposes or lands with low inherent productivity. This ruled out existing crop lands, pasture lands and forests.

They also determined that biofuel crops would be watered by rainfall and not irrigation, thus eliminating the need to redirect water from agricultural lands.

Three scenarios were considered for land availability under the research. Initially, the researchers limited the scope of available areas to idle land and vegetation land with marginal productivity.

Under this scenario, the researchers concluded that 320 million hectares of land would be available for biofuel production.

In the second scenario, they included degraded croplands, abandoned areas and wastelands. They calculated a total land area of 702 million hectares available for second generation biofuel crops such as switchgrass or miscanthus.

Finally, they expanded the study scope to include marginal grasslands. According to the researchers, a class of crops that can grow in this area, called low-impact high-diversity perennial grasses, are suitable feedstock for biofuel production.

These crops have a lower ethanol yield compared to grasses such as miscanthus or switchgrass. But they also have limited environmental impact and are largely similar to the natural land cover of grasslands.

Including marginal grasslands to the cropland estimate from the previous scenarios almost doubles the available land area in the world to 1,107 billion hectares – an area capable of producing enough biofuel to meet up to 56 percent of the current global liquid fuel consumption total.

Africa alone holds over 33 percent of the total available land in all the scenarios. Combined with Brazil, the two countries own over 50 percent of all the land estimated in the study. Following this research, the team plans to determine the potential impact of climate change on land use and availability.

“Based on the historical data, we now have an estimation for current land use, but climate may change in the near future as a result of the increase in greenhouse gas emissions, which will have effect on the land availability,” said Xiao Zhang, a graduate student and co-author of the paper.

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