Greenhouse gas emissions and agronomic effects from biochar applications at field scale in Norway...

Greenhouse gas emissions and agronomic effects from biochar applications at field scale in

Norway

Adam O’Toole, Hanna Silvennoinen*, and Daniel P. Rasse*presenting authorBioforsk Soil and Environment, Ås, Norway. www.bioforsk.no/biochar adam.otoole@bioforsk.no

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: 151-155 2Taghizadeh-Toosi, et al. (2011). JEQ 40(2); Zhang et al.(2012)Fld Crps Res. 127, 153-160 3 Jefferey et al. 2011. Ag. Eco. Env. 144: 175-187

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

Objectives of experiments

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‰

C3 SOM: ~ -30‰

OatsMiscanthus

δ13C

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

Biochar and Soil description

• Miscanthus giganteus (C4 plant) feedstock• Produced by Pyreg Gmbh (Germany)

Pyroysis temperature 500-750 °C• Fixed C = 70% VM= 7% Ash= 23%• pH: 10• BET: 349 m2 g-1

• Soil: Inceptisol, Sandy Clay Loam, TOC: 2.5 %

Field trials in Norway – 2010-13

Ås (University of Life Sciences, field station)

• Biochar inverse ploughed in the fall of 2010. New application in 2012 (mini plots for N2O study

• Crops – 2011 Oats 2012 Barley 2013 Oats

• Fertilizer: Ammonium Nitrate (NPK 22-3-10, 550 kg ha-1)

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

1. Control – no amendments

2. Straw 8t C ha-1 (2010)

3. Biochar 8 t C ha-1 (2010)

4. Biochar 25 t C ha-1 (2010)

5. Biochar 25 t C ha-1 (New application 2012 for N2O trial) (mini plots)

Air temp and precipitation (Apr-Nov 2012)

Results – Soil respiration

0,000

0,100

0,200

0,300

0,400

0,500

0,600

0,700

0,800

17.05.2011 06.06.2011 26.06.2011 16.07.2011 05.08.2011 25.08.2011 14.09.2011

g C

O2

m-2

h-1

Soil respiration 2011

Miscanthus 8t C ha-1

Control

Biochar 8t C ha-1

Biochar 25t C ha-1

2011 2012

No significant differences between treatments

Cumulative C loss – 2011-2012

C4 plant-C related loss

  CO2-C loss Contribution to CO2

Contribution to CO2

C loss from straw and biochar

g m-2 g m-2 % %

Control 461 - - -

Straw 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 daa-1 472 9 2 0.4%

~x 20

Straw and Biochar-C loss after Potassium Dichromate (K2Cr2O7) oxidation(Budai et al. In prep.)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Straw Bc 250°C BC 300°C BC 500°C Bc 700°C

Field

sit

e c

har~350-450°C threshold for inc. stability

apr mai jun jul aug sep okt

µg

N2O

-N m

-2 h

-1

0

200

400

600

800

1000

1200

1400

Control BC8 BC25 BC25 new

fertilization harvest

N2O flux 2012

Control BC8 BC25 BC25 new

kg N

2O

-N h

a-1

0

2

4

6

8

10

16.4.- 28.92.5.- 28.9

Cumulative N2O utslipp. 2012 growing season

BiocharClimate Saving Soils project (Interreg IV North sea programme)

17

“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 2009-2013

Project objective:

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• 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: 450-480°C

• Dose: 20t/haBiochar characteristics

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• 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

Transnational field trials

Grain yield (Barley) - 2012

Biokull Kontroll0

50

100

150

200

250

300

350

400

450

500

Bygg

kor

navl

ing

(kg

daa-

1)

Straw yield (Barley) 2012

Biokull Kontroll0

50

100

150

200

250

Bygg

kor

navl

ing

(kg

daa-

1)

Earthworm count in field

biochar control0

10

20

30

40

50

60

70

80

Total Earthworms collected from field site plots2 cores taken from 4 replicate plots per treatment (total 8 cores per treatment)

No.

of e

arth

wor

ms

Bulk density

Experiment 1• Control 1.30 g cm3 ± 0.04• Biochar 8 t 1.16 g cm3 ± 0.11• Straw 8 t 1.19 g cm3 ± 0.07• Biochar 25 t 1.22 g cm3 ± 0.05

Experiment 2• Biochar 1.06 g cm3 ± 0.05• Control 1.17 g cm3 ± 0.09

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

Thank you for your attention

Our website: www.bioforsk.no/biochar

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