soil as carbon sink: better soil is a bonus

soil color shows carbon content

You've read all the headlines about how sequestering CO2 is a growth business with huge potential.

Turns out, one of the best ways to tie up carbon and have it provide a useful function is incorporating it into the soil (via treehugger).

Fixing carbon (biochar) into the soil not only takes it out of the atmosphere, but also provides increases in crop production and soil health.

Better yet, carbon can stay in the soil for tens of thousands of years.

Researchers at Cornell report that bio-char (also called charcoal or biomass-derived black carbon) is a soil amendment that has the potential to revolutionize concepts of soil management.

Bio-char stands out among opportunities for sustainable soil management because of its retention of several nutrients that are essential to plant growth and its extremely high persistence.

These two properties can be used effectively to address some of the most urgent environmental problems of our time, idcluding soil degradation and food insecurity, water pollution from agro-chemicals, and climate change.

Says the Cornell team:

"Soils with bio-char additions are typically more fertile, produce more and better crops for a longer period of time."

Sure, all organic matter added to soil significantly improves various soil functions, yet what is special about bio-char is that it is much more effective in retaining most nutrients and keeping them available to plants than other organic matter such as common leaf litter, compost or manures.

The long persistence of bio-char in soil also make it a prime candidate for the mitigation of climate change as a potential sink for atmospheric carbon dioxide. The success of effective reduction of greenhouse gases depends on the associated net emission reductions through bio-char sequestration.

However, a net emission reduction can only be achieved in conjunction with sustainable management of biomass production.

During the conversion of biomass to bio-char about 50% of the original carbon is retained in the bio-char, which offers a significant opportunity for creating such a carbon sink.

So mebbe we could improve our Hawaiian soils by adding char from our new coal-fired ethanol plants.

Published by Ken on March 14th, 2007 tagged Climate Change, Community Initiatives

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