biochar presentation - lpelc · 2019. 3. 15. · biochar presentation: • biochar terminology •...

Using Biochars to Improve Soil C Sequestration and Fertility

Characteristics

Jeff NovakUSDA-ARS-CPRC, Florence SC

For: Livestock and Poultry EnvironmentalLearning Center Webcast (August 21, 2015)

1

Biochar presentation:

• Biochar terminology• Pyrolytic production• Characterization• South Carolina soil morphology• Use as a soil amendment• Biochar incubation studies

* Norfolk (SC)* Margate (FL)

• Conclusions

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Biochar terminology:

• Biochar is used to describe charred organic matter applied to soil with the intent to improve soil properties (Lehmann and Joseph, 2009).

• Popular terms to describe alternate C-enriched residues: – Charcoal, black carbon, char, activated carbon

3Charcoal bricks Char Activated C

Livestock and Poultry Environmental Learning Center Webcast Series August 21, 2015

This presentation is archived at: http://www.extension.org/pages/21819/chronological-webcast-archive

Overview of Pyrolysis:

Gas

(Syngas)

Liquid

(Bio-oil)

Solid

(Biochar)Pyrolysis

Biomass

Animal manure

Switchgrass Pine chips

Heat source required with low oxygen presence

4

Biochar characterization (pH):Feedstock Pyrolysis (°C) Mean pH (H2O) Source

Wood 400 6.9

500 8.8 Singh et al. (2010)

Cow manure 400 9.0

Hardwood 450 8.8 Jones et al. (2012)

Pecan shell 350 5.9 Novak et al. (2009a)

700 7.2

Poultry litter 350 8.7 Novak et al. (2009b)

700 10.3

Pine chips 465 6.1 Novak and Busscher (2012)

Corn stover 500 7.2

5As pyrolysis temperature increases, biochar pH can increase

Biochar characterization (nutrient):Feedstock Pyrolysis

(°C)Fertilizer equivalent ratio (kg/t

biochar)source

N P K

Swine manure 350 37 39 18 Cantrell & Martin, 2011

700 26 59 26

Cow manure 400 14 4 26 Singh et al. 2010

550 11 5 23

Poultry litter 350 50 30 60 Novak et al. 2009b

700 30 40 90

Pine chips 350 5 0.2 2 Novak et al. 2012

500 4 0.3 3

Switchgrass 250 4 1 5 Novak et al. 2012

500 11 2 12

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Biochars made from manures have higher fertilizer equivalent N P K ratios,and as pyrolysis temperature increases (> 500°C) N declines, P & K increase.



CoxvilleNorfolk

Bonneau

The Coastal Plain region of South Carolina (#27on map) comprises almost 2/3 of its total land area.

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These soils are farmed with row crops including corn, soybeans, cotton, wheat, tobacco, sorghum and truck crops.

Typical soil association in Florence, SC USA

%SOC in Sandy Coastal Plain soil profiles

soil organic carbon (SOC; % by wt.)

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8

soil

dep

th (

cm

)

-70

-60

-50

-40

-30

-20

-10

0

Bonneau (Ex. well drained) Norfolk (well drained) Coxville (poorly drained)

E horizon in aNorfolk series

Ap

E

Bt

A chisel plow is used to fracture the E horizon

Soil morphology and fertility

Coastal Plain soils formed in marine sediments and are between 3 to 5 million years old.Are sandy textured, have low SOC contents, and have with a poor ability to retain nutrients and water.Are dominated by kaolinitic clays.

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Can we improve agronomic aspects of soils by using biochars?

Biochars are being evaluated globally to determine their ability to increase soil C sequestration, improve soil quality,and raise crop yields.

There are several hundred reports showing both positive and negative soil quality improvements.

Meta-analysis of literature showed a 10% positive increase in crop productivity in soils receiving biochar (Jeffrey et al., 2011).

Photos courtesy of Karamat Sistani,USDA‐ARS‐Bowling Green , KY



Examples of biochars used for soil fertility improvement.– -- Norfolk loamy sand (Ultisol in SC)

– -- Margate sand (Entisol in FL)

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Norfolk loamy sand has low SOC content, and a poor nutrient and water retention capacity.

Margate sand has an alkaline soil pH thatlimits micronutrient availability.

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Norfolk loamy sand (Ultisol) fertility characteristics (Novak et al. 2009)¹

Mehlich-1 extractable (lbs/ac)

Treatment (°C) pH (H20) SOC (%) P K

Control 5.6 0.31 63 44

Pecan shell (500) 6.3 1.55 55 139

Poultry litter (700) 8.4 1.16 1647 638

Switch grass (500) 7 1.96 75 197

Hardwoods (500) 6.6 1.72 51 144

Peanut hull (500) 7.8 1.95 64 401

¹biochars added at 40 mt/ha (9 g/450g soil); incubated for 120 d

Not all biochars were effective at improving soil fertility.Manure biochars contain excessive P and K and can have an environmental impact. For Norfolk soils, a soil test recommendation for 100 bu/ac corn crop is:

-- soil pH 5.8 to 6.4-- Mehlich 1 extractable nutrient sufficiency levels are for P -- 31 to 80 and -- for K are 71 to 182 lbs/ac, respectively (Clemson Extension Service).

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Margate sand (Entisol) fertility characteristics (Novak et al. 2014)¹

Mehlich-1 extractable (mg/kg)

Treatment (°C) pH (H20) CEC (cmol/kg)

P K

Control 7.5 (0.2)a 6.2 (0.7)ac 130 (11)a 21 (2)a

Bagasse (350) 7.6 (0.1)a 5.3 (0.1)a 125 (4)a 26 (2)a

Pine chip (350) 7.6 (0.1)a 5.6 (0.6)ac 125 (5)a 25 (2)a

Hydrochar 1 7.4 (0.0)a 5.2 (0.3)a 129 (8)a 26 (2)a

Hydrochar 2 7.2 (0.0)b 4.7 (0.2)ab 122 (2)a 23 (2)a

Swine solids (350) 7.7 (0.0)a 6.8 (0.6)c 403 (63)b 52 (8)b

¹biochars and hydrochars added at 10 mt/ha (1.73g/450g soil); incubated for 120 d

Margate sand (Canal Point, FL)



Biochars and soil fertility wrap up:

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Biochars can improve soil C sequestration because they are C‐enriched, but some biochars are nutrient poor because of feedstock and pyrolysis temperature selection.

Some biochars contain excessive plant nutrients and are calcareous, so soil pH and fertility characteristics can be impacted.

These finding lead to the realization that not all biochars are effective at improving all soil quality deficiencies.

Dr. Jim Frederick, Clemson Univ.



biochar presentation - lpelc · 2019. 3. 15. · biochar presentation: • biochar terminology •...

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