Biochar and Soil Health

Johannes LehmannDepartment of Crop and Soil Sciences, Cornell University

Biochar InterestEarly reports: Encyclopedia of Agriculture (Miyazaki, 1697) Terra Preta (Orton, 1870; Hartt, 1880; Sombroek, 1966) Charcoal use in soil (Allan, 1846; Trimble, 1851; Liebig, 1878)

withoutbiochar

withbiochar

Retan 1915 Forestry Quarterly

©J.

Maj

or, 2

003

“Terra Preta”‘normal’ soil

Terra Preta

‘normal’ soil

(Central Amazon, Brazil)

©B

. Gla

ser,

2001

The Terra Preta - Biochar Story

“Naturally” Biochar-rich and Fertile Soils

Downie et al 2011, AEE 140, 137-147Mao et al., 2012, Env Sci Techn, publ online

Iowa Mollisol: 50% (of OC) biocharAustralia

Black Carbon Rich Soils Globally

Black Carbon Rich Soils Globally

Krull et al, 2008, in: Nova Sci Publ

Biochar Conversion

Lehmann et al., 2010, in: Imperial College Press, London

H2OCO, CO2, CH4volatile organics O

O

OH

O O

O

OCH2

OH

OHOH

O OH

OH

O

OH

O+ CH3

HO

CH+

O

OH

O

OH

HOHO

OH

OHO

OOH

OH

OH

n

O

H

HH

H

OH

H OH

O

OH

O OH

H

HH

OH

H

OH

OH

OH

Cellulose, Lignin etc. Amorphous Carbon Turbostratic Carbon

O/C 0.7 0.5 0.3 0.1H/C 1.5 1.0 0.5 0.3Temperature ~200°C ~400°C ~600°C

Relative Proportion

Pyrolysis Intensity

Biochar Persistence

Biochar persistence about 1-2 orders of magnitude greater than uncharred feedstock (Kuzyakov et al., 2009; Zimmerman, 2010)

Biochar Persistence in Soil

H/Corg ratio

0.2 0.4 0.6 0.8 1.0 1.2

MR

T (y

ears

)

100

1000

10000(a)

0.48

MRT=6439 e-2.8(H/Corg)

r2=0.12n=47, p<0.05

H/Corg

0.2 0.4 0.6 0.8 1.0 1.2B

C10

0 (%

)0

20

40

60

80

100(c)

Regression:BC100=-30.1(H/Corg) +105r2=0.44n=47, p<0.01

Threshold:BC100=-73(H/Corg) +116

Lehmann et al, forthcoming

Biochars with low H/Corg ratios have high persistenceBiochars made at >500ºC from wood has H/Corg <0.48

Biochar Properties and Agronomic Value

Corn greenhouse experimentUpstate NY loamy soil (no significant fertility constraints)Eight different feedstocksFour different temperatures (300-600°C)

Rajkovich et al., 2012, BFS 48, 271–284

Dependency on Biochar Properties

Dairy Manure Food Waste

Paper Mill Waste

PoultryControl 100

0.20.5

2.0

7.0

Tota

l Bio

mas

s (g

pot

-1)

0

5

10

15

20

300ºC

20 Corn greenhouse trialUpstate NY loamy soilN=2 (mean ±SE)

Biochar application rate (% w/w)

Control

Rajkovich et al., 2012, BFS 48, 271–284

Production Temperature vs Feedstock

Mean

Poultry manure 16.8 A

Corn stover 15.4 B

Hazelnut shells 14.3 C

Dairy manure 14.2 C

Oak 13.8 CD

Paper waste 13.7 CD

Pine 13.5 D

Food waste 10.3 E

Mean

500°C 14.4 A

600°C 14. AB

400°C 13.8 BC

300°C 13.7 C

Rajkovich et al., 2012, BFS 48, 271–284

Production Temperature vs Feedstock

Effects df MS df MS F value P

Effect Effect Error Error

Feedstock (F) 7 109.3 128 1.58 69.2 0.0000

Pyrolysis temperature (PT) 3 7.8 128 1.58 5.0 0.0028

Application rate (AR) 3 133.7 128 1.58 84.6 0.0000

F PT 21 8.3 128 1.58 5.2 0.0000

F AR 21 29.8 128 1.58 18.9 0.0000

PT AR 9 3.5 128 1.58 2.2 0.00235

F PT AR 63 5.1 128 1.58 3.2 0.0000

Rajkovich et al., 2012, BFS 48, 271–284

Production Procedure vs Feedstock

Food

Food

Cocon

ut

Food

FoodOak

Woo

d

Paper

Contro

l

PineOak

Hazeln

ut

Corn

Pine

Paper

Hazeln

ut

Oak

Leav

es

Pine

Paper

Kuikui

Hardw

ood

Switchg

rass

Pine

Dairy

PinePine

Dairy

Brush

Woo

d

Oak

Dairy

Hazeln

ut

Hazeln

ut

Dairy

Grass

Soybe

an

Dairy

Poultry

Dairy

Mixtur

e

Peanu

t

Rice hu

sk

Paper

PoultryCor

n

Softwoo

d

Corn

Corn

Corn

Mixtur

e

Poultry

Switchg

rass

Poultry

Poultry

Tota

l Bio

mas

s (g

pot

-1)

0

5

10

15

20

25ControlSlow pyrolysisFlash pyrolysisFast pyrolysisUpdraftTorrefactionGasificationActivated carbon

*

*

* * ***** * ***

** * ****

**

Rajkovich et al., 2012, BFS 48, 271–284

Biochar Properties and Agronomic Effects

Slow pyrolysis

0 10 20 30 40 50 60

pH K

Cl

4

6

8

10

12

cow manureannual biomasswoody biomasshigh-ash waste

(a) Ash (% w/w)

Ash (% w/w)

0 10 20 30 40 50 60pH

KC

l

4

6

8

10

12

(b)

cow manureannual biomasswoody biomasshigh-ash waste

Arrows from lowest to highest temperature within a given feedstock

Ash (% w/w)

Enders et al.,2012, Biores. Techn. 114, 644-653

Biochar Properties and Agronomic Effects

Van Zwieten et al., 2010, Plant and Soil 327:235–246

Australia10 t/ha biochar from paper mill waste+ wood chips (550°C; pH 9.4; 8.2)

Cheng et al, 2008, GCA, 72, 1598-1610

Biochar and Nutrient Retention

2 3 4 5 6 7 8 9 10 11

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10 11

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

50

100

150

200

250

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

2 3 4 5 6 7 8 9 10

0

500

1000

1500

2000

2500

pH

Surf

ace

char

ge (m

mol

e kg

C-1

)

New-BCHF

BC30

BC70 QC

NY

BC-HA

New-BCGW

CT

Negative chargePositive charge

Point of zeronet charge(PZNC)

>2000

<20 >7

<3

130-year-old Biochar(from pig iron production) in comparison to biochar made with traditional kilns

Biochar and Nutrient Retention

Liang et al., 2006, Soil Sci. Soc. Am. J. 70: 1719-1730

Organic Carbon (mg g-1)

0 10 20 30

Cat

ion

Exc

hang

e C

apac

ity (m

mol

c kg-1

)

0

100

200

300

r2=0.909CEC=2.81C+9.1

r2=0.784CEC=8.60C-18.6

Anthrosols

Adjacent Soils

DSACULGHAT

Other Anthrosols (Sombroek et al., 1993)

Biochar-rich terra preta soils

Biochar-poor soils

Laird et al, 2010, Geoderma 158, 436-442

Biochar Properties and Nutrient Leaching

Typic Hapludoll, IowaHardwood charcoalColumn experiment, n=6

Biochar Effects on N Use Efficiency

Corn field experimentBiochar application in 2007Corn stover biochar (550°C)Nitrogen study in 2009N-15 labeled NH4 (10 atom%)N=3

Guerena et al., 2013, Plant Soil

Year Secondary N fertilizer

Total N uptake (kg total N ha-1)

(% of recommended

fertilizer application)

0 t ha-1 12 t ha-1 p (biochar effect)

2007 50 55.69 46.61 0.5996 100 68.77 58.68 0.2596

2008 50 78.26 80.44 0.8683 100 116.22 116.28 0.9958

2009 50 72.88 69.55 0.7416 100 112.28 121.58 0.4565 2010 50 97.50 87.82 0.7899 100 113.01 116.23 0.7294 p (N effect)

0.0117 0.0048

Biochar Effects on N Use Efficiency

Guerena et al., 2013, Plant Soil

One order of magnitude greater NO3 than NH4leaching

More organic N leaching than NH4 leaching

Biochar Effects on N Use EfficiencyOrganic Nitrogen Retention in Soil?

*

Guerena et al., 2012, Plant Soil

Equilibrium concentration (mg N L-1)

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

Adso

rbed

DO

N (m

g N

g-1

)

-15

-10

-5

0

5

10

15

Control (0 t ha-1)Biochar (12 t ha-1)

y = 4.60x - 16.2r2 = 0.76

y = 4.66x - 24.3r2 = 0.30

Biochar Effects on N Use Efficiency

Van Zwieten et al., 2010, AJSR

Similar plant growth at lower N application

Biochar Effects on Denitrification

N2O emission decrease by 10-90% in 14 different agricultural soils

In 10 out of the 15 measured soils, also the total N denitrified between 4 and 232%

Cayuela et al., 2013, sumitted

Fluxes of N2 and N2O when the difference between biochar and control N2O fluxes was maximum**

Soil

N2 (mol kg-1 soil h-1)

N2O (mol kg-1 soil h-1)

N2O/(N2 + N2O)

  Control  Biochar  Control Biochar Control Biochar

Elba

2.75 3.03

17.39 17.99

0.864 0.856

Lins 0.06 0.06 2.26 0.44 0.972 0.850

Arkport 15.77 4.82 0.54 0.09 0.053 0.038

Lentiscosa 3.41 23.73 4.45 2.34 0.550 0.159

Tioga 0.12 0.14 1.43 0.38 0.820 0.651

Howard 1.23 2.08 7.46 9.39 0.793 0.766

Secanos 5.23 0.76 3.64 0.61 0.443 0.394

Cabezo 10.95 4.29 1.74 0.67 0.295 0.142

Hudson A 0.22 0.22 0.36 0.48 0.607 0.291

Madalin 0.58 0.97 3.64 0.17 0.795 0.130

Niagara 0.41 1.06 18.53 9.10 0.971 0.854

Hudson B 3.59 4.04 7.28 4.61 0.643 0.511

Costa 7.79 14.25 5.67 2.36 0.458 0.179

Coronela 14.49 2.26 9.99 1.47 0.468 0.244

Guarapuava 0.17 0.09 1.63 0.14 0.782 0.447

Values are the mean of 4 replicates.  

Biochar Effects on DenitrificationReason for decreases in denitrification

Cayuela et al., 2013, sumitted

-0.4 1.0

-0.6

0.8

Total N denitrified (N2 + N2O) decreases

ratio N2O/(N2 +N2O) decreases

Cumulative N2O decreases

Tsand

T silt

TclayDOC

pH

NO3-

NH4+

Lins

Arkport

Secanos

Tioga

Lentisc

Guarap

CabezoHoward

HudsonA

Niagara

Coronela

Madalin

HudsonB

Costa

Biochar Effects on Soil Biota

Lehmann et al, 2011, Soil Biol Biochem 43, 1812–1836

(a) (b)

(c) (d)

• Microorganisms observed on biochar surfaces

• Total microbial biomass increases in most studies

• Effects largely unexplored

Biochar Effects on Plant Disease

Elmer and Pignatello, 2011, Plant Disease 91, 960-966

Fusarium on asparagus

Biochar Effects on Plant Disease

Elad et al, 2010, Phytopathology 100, 913

Grey mold on tomatoArea under disease progression

Several studies have shown disease reductions with biocharadditions.Mechanisms unclear, longevity of effect unquantified

Biochar Products

Biochar as a System

Biochar Systems – Beyond Material