1. Greenhouse gas emissions and agronomic effects from biochar applications at field scale in Norway
Adam O’Toole, Hanna Silvennoinen*, and Daniel P. Rasse
*presenting author
Bioforsk Soil and Environment, Ås, Norway.

2. Introduction
Biochar-C stability? Is linked to pyrolysis temp. at which biochar is produced1, however limited field data showing the extent of biochar-C mineralization and effects on native SOM mineralization in ag. soils (eg. Does Priming of SOM occur?)
GHG impact?: Previous studies2 have shown reductions of N2O in biochar amended fields but no field data show the duration of this effect.
Agronomy? Meta analyses3 estimate ~10% average yield increases in biochar studies, but little published data avail. for Nordic countries
1Mašek et al. 2011, Fuel. 103: Taghizadeh-Toosi, et al. (2011). JEQ 40(2); Zhang et al.(2012)Fld Crps Res. 127, Jefferey et al Ag. Eco. Env. 144:

3. Objectives of experiments
Experiment 1: To estimate the stability of biochar-C under field conditions and BC impact on GHG emissions Experiment 2: Assess agronomic impacts from biochar application as part of a Northern European ring trial.

4. Methods for assessing Biochar C stability
Measuring the δ13C signature and CO2 efflux of a C3 soil after additons of Miscanthus (C4 plant) derived biochar
C4 plants: ~ -15‰
δ13C
Miscanthus
Oats
C3 SOM: ~ -30‰

5. Methods: Experiment 1
GHG measurement: Closed static chambers, Infrared gas analyzer (IRGA) for CO2 efflux (2 mins per chamber), Piccaro G1101-i for δ13C measurements
Keeling plot method used to isolate soil respired CO2 in chamber measurements (3, 8, 1440 min).
Larger closed chambers for N2O, vial measurements taken at 0,15,30, 45 min. and measured via GC

6. Biochar and Soil description
Miscanthus giganteus (C4 plant) feedstock
Produced by Pyreg Gmbh (Germany) Pyroysis temperature °C
Fixed C = 70% VM= 7% Ash= 23%
pH: 10
BET: 349 m2 g-1
Soil: Inceptisol, Sandy Clay Loam, TOC: 2.5 %

7. Field trials in Norway – 2010-13
Biochar inverse ploughed in the fall of New application in 2012 (mini plots for N2O study
Crops – 2011 Oats Barley Oats
Fertilizer: Ammonium Nitrate (NPK , 550 kg ha-1) Ås
(University of Life Sciences, field station)

8. Experimental Design
16 plots (6 x 4 m) / 4 plots (1.5 x 1.5 m miniplots)
5 treatments x 4 reps
Randomized block design
Control – no amendments
Straw 8t C ha-1 (2010)
Biochar 8 t C ha-1 (2010)
Biochar 25 t C ha-1 (2010)
5. Biochar 25 t C ha-1 (New application 2012 for N2O trial) (mini plots)

9. Air temp and precipitation (Apr-Nov 2012)

10. Results – Soil respiration
2011
2012
No significant differences between treatments

12. Contribution to CO2 flux
Cumulative C loss –
C4 plant-C related loss
CO2-C loss
Contribution to CO2
C loss from straw and biochar
g m-2 %
Control
461 -
Straw t C ha-1
467 76 16
9.5%
Biochar t C ha-1
439 5 1
0.6%
Biochar t C daa-1
472 9 2
0.4%
~x 20
Table 1. Degradation of C4 products and contribution to Soil-C flux ( )
C4 related loss
CO2-C loss
amount
Contribution to CO2 flux
loss of C4 inputs
g m-2 %
Control
461 -
Miscanthus 8 t C ha-1
467 76 16
9.5%
Biochar 8 t C ha-1
439 5 1
0.6%
Biochar 25 t C ha-1
472 9 2
0.4%

13. Straw and Biochar-C loss after Potassium Dichromate (K2Cr2O7) oxidation (Budai et al. In prep.)
~ °C threshold for inc. stability
Field site char
Straw Bc 250°C BC 300°C BC 500°C Bc 700°C

14. N2O flux 2012
fertilization
harvest

15. Cumulative N2O utslipp.
2012 growing season

16. BiocharClimate Saving Soils project (Interreg IV North sea programme)

17. Project objective:
“To develop, implement and disseminate the biochar-strategy in the North Sea Region (NSR) for climate change adaptation and climate change mitigation by increasing soil quality and stability with soil biochar amendments.”
7 countries around the North Sea:
UK, NO, SE, DK, DE, NL, BE
Period

18. Biochar characteristics
Field trial objective:
“To test the effect of one wood based biochar on soil quality and crop growth according to a standard protocol, across different soil types and climates of the North Sea Region.”
Feedstock: mix of Picea abies - Abies alba - Pinus sylvestris -Fagus sylvatica - Quercus robur
Pyrolysis temperature: °C
Dose: 20t/ha
Biochar characteristics
Biochar characteristics

19. Biochar characteristics
Transnational field trials
Biochar application date in Norway: spring 2012
Treatments: 1) biochar, 2) control
Replicates: 4
Crop
2012: spring barley (DE: winter wheat)
2013: free crop choice
Biochar characteristics

20. Grain yield (Barley)

21. Straw yield (Barley) 2012

22. Earthworm count in field

23. Bulk density Experiment 1 Control 1.30 g cm3 ± 0.04
Biochar 8 t g cm3 ± 0.11
Straw 8 t g cm3 ± 0.07
Biochar 25 t g cm3 ± 0.05
Experiment 2
Biochar g cm3 ± 0.05
Control g cm3 ± 0.09

24. Conclusion Biochar appeared to be Stabil and did not prime native C
Plant yields similar over all treatments in two wet seasons in a clay loam Norwegian soil
Reductions in bulk density and increases in worm populations could have a benefits for root growth, but needs more study

25. Thank you for your attention
Acknowledgements
Raphael Fauches
Monique Carnol, University of Liege
Svend Pung – SKP, UMB
Toril Trædal (UMB)
Christophe Moni, Farshad Tami
and Robert Barneveld
Funding: Matprogrammet, Norwegian Research
Council. Interreg IV NSR program and SLF
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