Biochar Claims Overblown

EU scientists suggest changing the name from biochar to plant charcoal.

| July 19, 2012

This report is posted with permission from Woods End Laboratories. 

The re-discovery of “Terra Preta” in the Amazon Basin marked for soil scientists a possible turning point: the idea that an ancient practice could provide insight into correcting CO2 build-up and staving soil decline. “Millions of Euros have been spent now on biochar studies.” conference organizer for the Berlin October 2011 ANS-Symposium intoned. Far from the near-panacea biochar in USA presents for saving climate and soil, the European lab tests along with tough EC climate regulatory debate “cast doubt that significant progress will be made until many questions are answered.” The Institut für Agrarrelevante Klimaforschung presented data showing variable carbon-stability and summarized soil-plant studies confirming that negative effects are almost as common as positive effects. The big topic was lab tests which suggest biochar carbon has as little as 35 percent stability or possibly “climatologically irrelevant.”

Editor Dr. Kehres (Journal “Humus and Agriculture“) summed up the symposium: “Biochar appears over-rated — the biochar claim to 1,000 year stability is revised downwards to 10 to100 years, roughly the same as compost.” Details on the fractions of carbon from pyrolysis, HTC and other carbonizing methods weighed against the lack of method standards, plus rankling over carbon legislative validation, suggest a biochar future “if even economical” faces many hurdles.

The symposium eventually turned to name calling: it was proposed to drop the prefix “bio” from biochar, a “technical misnomer” – and a source of confusion in Europe where “bio” means certified natural farming. What’s the name to be? - “Plant Charcoal” (“Pflanzenkohle – it’s more accurate”). 

This report is reprinted with permission from Woods End Laboratories.  Woods End specializes in examining soils for active carbon, measuring biological degradation and stabilization of organic wastes and the fate and effects of agri-chemicals in soil and compost environments.  Currently they offer advisory and custom research services ranging from individual clients to Fortune 500 firms. 


Beau Webber
2/10/2013 3:07:47 PM

Many of the basic studies we need on biochar are still being done, both to establish optimum preparation conditions for soil improvement and for long-term carbon sequestration - and the optimum for one is unlikely to be the same as for the other. For instance, a biochar with lots of labile organic content (low preparation temperature) is good for feeding soil organisms, but may be fairly hydrophobic. A biochar with high preparation temperature will have less labile organic content, and will mostly be a fairly hydrophilic empty carbon skeleton - this is likely to last a very long time in the soil. Many people are making longevity test, and studying the chemical properties of biochar. My company - - makes physical measurement using NMR, of the amount of residual labile hydrocarbon content in the biochar, and of the remaining free-pore volume distributions. These are relevant to soil improvement, water retention, and carbon sequestration lifetime. A paper summarising these techniques has been presented at the mrpm11 conference, and has been submitted to a journal for publication.

Lynn Lough
7/26/2012 6:13:26 AM

for anyone interested in, or confused by, Biochar soil technologies, Please view my presentation and slides coming up this week in Sonoma California. This is the third US Biochar conference, after ISU 2010 and Colorado 2000 09. Carbon Conservation for Home, Health, Energy & Climate

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