Long term Biochar versus Wood Ash Agronomic Field Trial at 6 months Dr Eleanor Swain, Prof Davey Jones, Prof Dave Chadwick, Dr Paul Hill 25th March 2015

Long term Biochar versus Wood Ash Agronomic Field Trial Experimental Aims: Directly compare the agronomic value of BC versus WA when used in grassland management Evaluate the impact of BC and WA on soil quality at the field scale over multiple seasons The trial was set up to evaluate whether the product of wood pyrolysis (i.e. biochar) was better than the product of incineration (i.e. wood ash) when used in grassland management (for sheep grazing and silage production). We are studying various aspects of soil and plant quality within this trial including forage growth and yield, soil biodiversity, greenhouse gas emissions, soil nutrient effects, nitrogen and carbon dynamics, water dynamics etc.  http://www.bangor.ac.uk/senrgy/research/facilities/henfaes_wood_ash.php.en

Biochar Organic material burned in the absence of O2 Bi-product of bioenergy Carbon sequestration in soil using biochar Potential secondary agronomic benefits

Wood ash Residue remaining after the combustion of wood Acts as a liming agent Neutralizes soil acidity Reduces Al toxicity Potential secondary agronomic benefits source of Ca, K, Mg and P provide a significant source of nutrients; Ca, K, Mg and P (Someshwar 1996, Kuba et al., 2008), raising the theory that ash could be utilised as a fertilizer (Kuba et al., 2008).

Long term Biochar versus Wood Ash Agronomic Field Trial Experimental Set-Up: Randomised block design field trial Biochar was added at 10 t ha-1 in 2014 Wood ash was added at a rate equivalent to 10 t ha-1 of biochar which equated to 0.57 t ha-1 (i.e. ash content of biochar ca. 5.7%) Mixed hardwood biochar powder to maximise its surface area (the old trial used large biochar chips). The wood ash was created from the biochar so that they were directly comparable.

Long term Biochar versus Wood Ash Agronomic Field Trial Experimental Set-Up: Randomised block design field trial Biochar was added at 10 t ha-1 in 2014 Wood ash was added at a rate equivalent to 10 t ha-1 of biochar which equated to 0.57 t ha-1 (i.e. ash content of biochar ca. 5.7%) Mixed hardwood biochar powder to maximise its surface area (the old trial used large biochar chips). The wood ash was created from the biochar so that they were directly comparable. Mixed hardwood BC powder

Long term Biochar versus Wood Ash Agronomic Field Trial Experimental Set-Up: Randomised block design field trial Biochar was added at 10 t ha-1 in 2014 Wood ash was added at a rate equivalent to 10 t ha-1 of biochar which equated to 0.57 t ha-1 (i.e. ash content of biochar ca. 5.7%) Mixed hardwood biochar powder to maximise its surface area (the old trial used large biochar chips). The wood ash was created from the biochar so that they were directly comparable. Wood ash created from the combustion of biochar

Biochar & Wood ash Long term Trial with long term CO2 flux chambers at Henfaes Farm, Bangor University (18/09/14)

Biochar & Wood ash Long term Trial with long term CO2 flux chambers at Henfaes Farm, Bangor University (07/10/14)

Biochar & Wood ash Long term Trial with long term CO2 flux chambers at Henfaes Farm, Bangor University (10/03/15)

Soil Quality: soil moisture

Soil Quality: pH

Soil Quality: SOM, C & N

Soil Quality: soil nutrients

Soil Quality: soil nutrients

Soil Quality: PLFA Analysis Microbial community biomass & structure Using the whole PLFA pattern have there been changes in the community due to a specific treatment? Using specific PLFAs as markers to specific groups have treatments had an effect on specific groups of microorganisms?

Agronomic Value: Grass 1st Cut (Nov 2014)

Preliminary Conclusions: 0-6 months Relative to the Control: BIOCHAR ↑ SM 2% ↑ SOM 1.8% ↑ pH 0.4 units ↑ NO3-N 55% ↑ C & N in grass Relative to the Control: WOOD ASH ↑ pH 0.25 units ↑ NO3-N 40% ↑ P in grass ↓microbial biomass

Future Work: 6-12 months Continue to monitor soil quality properties Measure crop parameters Evaluate long term CO2 emissions

Acknowledgements Any Questions? Prof. Davey Jones Prof. Dave Chadwick Dr. Paul Hill Lab Technicians: Sarah Chesworth & Gordon Turner Field Technicians: John Evans & Alex King Henfaes Staff: Llinos Hughes & Mark Hughes Any Questions?

Lab Work Soil priming Sorption Microbial biomass C & N