High nitrogen supply alleviates reduced sugarbeet growth caused by hydrochar application Heinz-Josef Koch & Ana Gajić Institute of Sugar Beet Research,

High nitrogen supply alleviates reduced sugarbeet growth caused by

hydrochar application

Heinz-Josef Koch & Ana Gajić

Institute of Sugar Beet Research, Goettingen, Germany

2012 US Biochar Conference – Sonoma (CA), 29.07.-01.08.2012.

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Introduction | Material and Methods | Results and Discussion | Summary and Outlook

In Germany, increasing cultivation of energy crops and use of crop residues for energy production has considerably reduced the amount of crop residue left on arable fields

The German Federal Soil Protection Act stipulates that "the site-specific soil humus content must be preserved by the agricultural practices applied, in particular by an adequate supply of organic matter ...“

To prevent humus depletion of arable fields, alternative practices and concepts must be developed (e.g. biochar, hydrochar)

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F. Bergius (1913) – HydroThermal Carbonization Biomass → hydrochar + process water + gas + heat Processing conditions:

aqueous solution (acidic), 180 - 250 °C, 4 - 12 h Carbon conversion efficiency ~ 90%

Hydrochar (HTC-biochar) Lignite alike product

Energy production

Large specific surface areaNutrient storage and buffering?

Porous structureWater storage?

Decomposition stability Carbon sequestration?

HTC

Hydrochar nanoparticles


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The aim of this study was to investigate the effect of hydrochar on sugar beet growth and mineral N (Nmin) availability

on typical German arable soils.


Hydrocharmade from

Plant available nutrients -------- Other properties -----NNO3, NH4 PCAL KCAL MgCaCl2

Ct Nt C:N pH EC

[g kg-1] [%] [%] [ ] [ ] [mS cm-1]

Beet pulp 0.3 0.5 0.4 0.2 50.1 1.3 38.3 5.9 2.8

Draff** 0.4 1.0 0.3 0.5 54.4 3.5 15.5 5.3 2.3

* VDLUFA - horticultural substrates **Spent grains

Hydrochar production conditions: 12 h, 190 °C

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Site Goettingen, 2010

Field trial (51 N, 10 E)

Luvisol (loessial), temperate climate (620 mm, ~9 °C)

2 factorial (split-plot, 4 replicates)

1. Hydrochar (H)

Control, Beet pulp, Draff

2. Nitrogen fertilization (N)

0, 50, 100, 150 kg N ha-1

Hydrochar 10 Mg ha-1 (dm)

Test crop: Sugar beet

(April – October)

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Beet pulp / N0

DC 10cotyledon

DC 122-4 leaves

DC 144-6 leaves

Introduction | Material and Methods | Results and Discussion | Summary and OutlookS

eedl

ing

emer

genc

e [%

]

0

20

40

60

80

100

Control Beet pulp Draffkg N ha-1:

DC 10 DC 12 DC 14

H ns | N ns | HxN ns

May:Hydrochar effect on seedling emergence and growth

Growth stage:

----------Hydrochar----------

7June harvest:

Hydrochar effect on sugar beet yield and N content


Sin

gle

plan

t yi

eld

[mg,

dm

]

0

200

400

600

800

1000

N c

onte

nt [

% in

dm

]

0

4

6

8

10 Yield H ** | N ** | HxN **N content H ns | N ** | HxN ns

kg N ha-1:

Control Beet pulp Draff

cd

dd

a

b

bc bc bcb

----------Hydrochar----------

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Hydrochar effect on

Soil Nmin (N-NO3 + N-NH4)


05. May 09. Jun 07. Jul 30. Sep

Nm

in 0

-90

cm [

kg N

ha-1

]

0

50

100

150

200

250

aa

b

ns ns *** nsSampling:

ControlBeet pulpDraff

Nmin 0-30 cm

28. Jun

12. Jul

26. Jul

09. Aug

24. Aug

06. Sep

Leaf

Are

a In

dex

[m2 m

-2]

0

1

2

3

4

ControlBeet pulpDraff

and Leaf Area Index

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October harvest: Hydrochar effect on

Beet N Uptake


Adj

uste

d su

gar

yiel

d [M

g ha

-1]

0

10

11

12

13

Control Beet pulp Draffkg N ha-1

H ** | N ns | HxN **

aba

cb

cb

cb

cb

cb

c cb

cb

cba

cba

0 50100

150 0 50100

150 0 50100

150

Bee

t N

upt

ake

[kg

ha-1

]

0

50

75

100

125H ** | N ** | HxN ns

kg N ha-1:


B A B

--------Hydrochar-------- -------Hydrochar--------

and White Sugar Yield

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IfZ Goettingen, 2011

Greenhouse trial

Cambisol (100 mg N kg-1), 1 kg soil pot-1

Block design (4 replicates)

1. Hydrochar (H)

Control, Beet pulp, Draff

2. Nitrogen fertilization (N)

0, 100, 200 mg N kg-1 soil

Hydrochar 30 Mg ha-1 (dm)

Test crop: Sugar beet


4 weeks of growing,20 °C, 40-80 % WHCmax

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Beet pulp

Beer draff

Beet pulp

Draff

ControlWhole plants harvested after 4 weeks of growing

Sin

gle

plan

t yi

eld

[mg,

dm

]

0

200

400

600

800

1000

N c

onte

nt [

% in

dm

]

0

2

4

6

8

10

c

e e

a

cd

de

b

e

e


mg N kg-1:

Yield: H ** | N ** | HxN **

ab

c

e

b

d

b

c

e

N content: H ** | N ** | HxN *

a

Hydrochar effect on single plant yield and N content


--------Hydrochar--------

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Hydrochar effects (10-30 Mg ha-1) on

Early sugar beet growth: Seedling emergence and establishment was not affected Seedling growth was significantly reduced at low N supply Increased N supply partly (field) or completely (greenhouse)

compensated for stunted early growth (toxic compounds?) Early growth reduction was more severe with hydrochar

from beet pulp (C/N 38) compared to draff (C/N 16)

Final sugar beet yield and quality: No yield decrease due to hydrochar, when N supply was adequate Beet pulp hydrochar (but not draff) reduced yield at low N supply Draff hydrochar slightly increased N uptake at low N supply


N immobi-lization

→ Re-mineralization of N

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Mean residence time (microcosm study):

Wheat straw (1 y) < Hydrochar (5-8 y) <<< Biochar (4x1012 y)

Hydrochar (30 Mg ha-1) effects on soil properties:

pH and CEC

Aggregate stability

Water holding capacity

Open questions

Optimum HTC conditions: feedstock, temperature, time?

Optimum crop and time of application?

Phytotoxicity?

C balance, energy balance, GHG emission?


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Thanks for Your attention!

Gajić, A. & Koch H.-J. (2012): Sugar Beet (Beta vulgaris L.) Growth Reduction Caused by Hydrochar Is Related to Nitrogen Supply. J Environ Qual doi:10.2134/jeq2011.0237.

Documents

High nitrogen supply alleviates reduced sugarbeet growth caused by hydrochar application Heinz-Josef Koch & Ana Gajić Institute of Sugar Beet Research,