Tuesday, November 20, 2007

Biofuels, Excess Nitrogen Fertilization,ect.

In the recent release "Biofuels: An Important Part of a Low-Carbon Diet" from the Union of Concerned Scientists, they discuss the role of biofuels along with increases in energy efficiency in reducing the carbon impact of personal transportation. In the article the UCS analysis recognizes the importance of reducing fuel consumption through increased efficiencyas well as miles driven. Acheiving this will require a significant adjustment to the way we live, and work. This demonstrates the degree to which energy policy, urban develoopment and environment are interconnected. For decades we have subsidized the sprawling development that has become the signature of most American urban areas. As a result we have become dependant on inexpensive and abundant transportation fuels.

Without significantly increased effeciancy and reduced miles driven there is little hope that biofuels can significantly impact our need for imported petrolieum fuels. They cite corn derived ethanol as being a elementary first step toward reducing the carbon intensity of the transportation sector.

And in walks Productive Conservation on Working Lands... By focusing on developing the supply of feed stocks for the bio-energy sector PCWL will aid in reducing imported and fossil fuel derived energy needs. This will be true weather the preferred technology is biomass gassification, cellulose ethanol, or co-burning biomass in conventional power plants.

In a study published in the Journal of Environmental Quality, a long term (50 years) study documents excessive N fertilizers deplete soil organic carbon. The Myth of Nitrogen Fertilization for Soil Carbon Sequestration reports the findings of a study that concludes: "The analysis came from a century of soil organic carbon data from the university’s Morrow Plots, the world's oldest experimental site under continuous corn. After 40 to 50 years of synthetic fertilization that exceeded grain N removal by 60 to 190 percent, a net decline occurred in soil carbon despite increasingly massive residue C incorporation." (excerpt from newfarm.org)

As soil carbon content decreases, that content is released to the atmosphere. By removing untold tons of sequestered CO2 and releasing it to the atmospheric CO2 pool, we are intensifying the accumulation of greenhouse gasses. Another negative effect of this shift of carbon is the reduction of soil fertility. It is well established that soils high in carbon content have increased ability to hold nutrients vital to crop production, and the depletion of carbon content in our soils is a major concern for the future productivity of our farm lands. We need to consider these long term consequences when deciding which agricultural practices we as a nation are going to support.

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