Thursday, January 20, 2011
Can Biomass Crops Be Produced Outside Of Food And Feed Crop Regions?
The global adaption of biofuels has been relatively quick, but as supply and demand issues begin to create economic challenges, biofuel politics has created a new generation of authorities who have completely different visions of the future. One of the controversies is how much land can be dedicated to biofuel production without infringing on food production. The typical consumer rhetorically asks that question as he or she drives to the grocery store and onto the gas station. In some parts of the globe land is needed for food, but does that mean all land is needed for food? And are there areas which may be more suitable for production of biomass that could be converted to biofuel? Those questions probably cannot be adequately answered by a windshield survey across your township. But what about the rest of the world?
The answer to that question was developed by a collaborative effort among three engineers from the University of Illinois and the University of Central Florida, who looked at marginal lands on all of the continents to evaluate the potential for production of low input, high diversity mixtures of native perennial plants which could become energy crops. Their report indicates that 27 to 34 million acres would be available for biomass production. That does not include crop or pasture land and would not interfere with any other agronomic issues. They estimate that by planting a second generation of biofuel feedstocks on the land that currently has marginal productivity; the result would provide 26% to 55% of the current world liquid fuel consumption.
The researchers took into account the impact on small scale farmers, threats to conservation, increase in carbon emissions, invasive species of plants, and land use change that impacts water use. The land they propose for biomass production would be considered “marginal agricultural land” which has been abandoned farmland, degraded land, wasteland, and idle land. It was all identified with the use of existing land data use and remotely sensed world cropland maps. The researchers had to determine soil productivity ratings, the slope of the land, soil temperature extremes, and a humidity index. They identified the land that may be a candidate for biomass production as grassland, savanna, or shrub land.
But what would be harvested for biomass and ethanol production? The researchers evaluated the net energy gain from 16 perennial grasses, and second generation biomass crops such as switchgrass and miscanthus. They determined the latter would produce more biomass for energy production through ethanol refining, than the perennial grasses that would be more native to the various regions. The researchers, who discounted the use of current pasture land, also discounted the use of forestland conversion to biofuel production. They did indicate there would be an opportunity to increase the marginal land for biofuel production throughout the course of cyclic changes of land use. The researchers also counted totally on rainfall for the biomass production, but indicated if irrigation were present, it would be beneficial to the yield.
They conclude that if abandoned or degraded agricultural land were used for biomass production, it would supply 10% to 52% of the current world liquid fuel consumption, if crops such as switchgrass or miscanthus were being produced. If marginal grasslands were added, but no pastureland, then the biofuel production would increase to 26% to 55% of current consumption. The researchers found that Africa has more than one third and South America more than one half of the total land available for biomass production. However, they say the market for the fuels are in the US, Europe, China, and India, but not in Africa and South America. They do express concern about certain environmental tradeoffs for carbon sequestration and the energy required for biofuel production. The researchers end by saying, “The challenges for the world are to identify the most highly productive plant species that can be grown on the various types of marginal or abandoned lands and to develop innovative land use systems specifically designed for energy crops that have high energy productivity and meanwhile support species diversity and community development.”
Summary:
A quarter to a half of the current global biofuels consumed could be produced on marginal agricultural lands and scrub lands throughout the world, over 80% of it in Africa and South America. Such lands could be planted with switchgrass or miscanthus to be highly productive, but the ethanol produced by local refineries would still have to be transported to developed countries.
Posted by Stu Ellis on 01/20 at 01:06 AM | Permalink