SOIL ORGANIC MATTER in the

BIOBASED ECONOMY

HANS VAN VEEN

Netherlands Institute of Ecology

www.nioo.knaw.nl

what is soil organic matter?

Soil Organic Matter, SOM, is the collective term representing all organic constituents in the soil, including undecayed plant and animal tissues, their partial decomposition products, and the soil biomass (http://karnet.up.wroc.pl)

what is SOM doing?

• Bind soil particles together in stable aggregates

• Influence water holding and aeration

• Major source of cation exchange capacity

• Source of pH buffering

• Binding site for heavy metals and pesticides

• Food source for microbes and small animals

• Major reservoir of plant nutrients (http://www.dpiw.tas.gov.au/inter.nsf)

Why care about SOM?

It largely determines soil quality!

soil’s ability to provide ecosystem and social services through its capacities to perform its functions under changing conditions EU definition

main soil functions

• Biomass production

• Storing, filtering and transforming nutrients, substances and water

• Biodiversity pool such as habitats, species and genes

• Source of valuable materials

• Acting as carbon pool

composition of SOM

T < 20 years T > 500 years

SOM = 2-10 % of Total Soil Matter

T < 2 years

humus formation

SOM Models

cultivation leads to SOM reduction

Van Veen & Paul, Can J Soil Sci, 61, 185-201,1981

Losses of soil organic matter due to cultivation

Country

____________

Years

of cultivation

____________

Loss

( % C or N)

____________

Reference

__________

Australia ? 50 Greenland, 1982

Canada 60-80 40-60 Campbell et al,

1976

Canada 70 57 Voroney et al,

1982

Canada 22 20 Newton et al,

1945

USA 60 40 Stevenson, 1965

reality of soil arrangement

soil degradation

resources of soil organic matter

Above ground residues

Root turnover products

biobased economy

biofuel demand Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

biomass types for

biobased energy

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

why care about SOM in the

bio-based economy?

Changes in quantity (< !) and quality of plant residue inputs

Impact on soil quality

SOM balance at various biomass production systems

-25 -20 -15 -10 -05 00 05 10 15 20 25

Suikerriet ethanol (top+blad verbrand)

Suikerriet ethanol (top+blad op veld)

Maïs ethanol

Soja FAME

Tarwe ethanol (stro op veld)

Stro ethanol (lignine retour)

Stro ethanol (lignine verbrand)

Suikerbiet ethanol (klei)

Suikerbiet ethanol (zand)

Palmolie FAME

Koolzaad FAME

Resthout voor CV

Resthout voor boiler

Resthout voor CFBC

Snijmais groen gas

Snijmais groen gas (+mest)

Snijmaïs WKK

Snijmaïs WKK (+mest)

SRC hout voor CFBC

SRC hout voor CV

SRC hout voor boiler

kg/GJ

Bodemorganischestofbalans

Straw residue removed residue left

Maize

Croezen, Odegard, Bergsma & Langeveld, Soil in the Bio-economy ( in Dutch), publ nr 13.2813.19, 2013, CE-Delft

Sugar cane, residue left residue burnt

Rape seed

CO2 emission-reduction at various biomass production systems

-25 -20 -15 -10 -05 00 05 10 15 20 25

Suikerriet ethanol (top+blad verbrand)

Suikerriet ethanol (top+blad op veld)

Maïs ethanol

Soja FAME

Tarwe ethanol (stro op veld)

Stro ethanol (lignine retour)

Stro ethanol (lignine verbrand)

Suikerbiet ethanol (klei)

Suikerbiet ethanol (zand)

Palmolie FAME

Koolzaad FAME

Resthout voor CV

Resthout voor boiler

Resthout voor CFBC

Snijmais groen gas

Snijmais groen gas (+mest)

Snijmaïs WKK

Snijmaïs WKK (+mest)

SRC hout voor CFBC

SRC hout voor CV

SRC hout voor boiler

kg/GJ

Bodemorganischestofbalans

Straw, residue removed residue left

Maize

Rape seed

Croezen, Odegard, Bergsma & Langeveld, Soil in the Bio-economy ( in Dutch), publ nr 13.2813.19, 2013, CE-Delft

-120 -100 -80 -60 -40 -20 0 20

Suikerriet ethanol (top+blad verbrand)

Suikerriet ethanol (top+blad op veld)

Maïs ethanol

Soja FAME

Tarwe ethanol (stro op veld)

Stro ethanol (lignine retour)

Stro ethanol (lignine verbrand)

Suikerbiet ethanol (klei)

Suikerbiet ethanol (zand)

Palmolie FAME

Koolzaad FAME

Resthout voor CV

Resthout voor boiler

Resthout voor CFBC

Snijmais groen gas

Snijmais groen gas (+mest)

Snijmaïs WKK

Snijmaïs WKK (+mest)

SRC hout voor CFBC

SRC hout voor CV

SRC hout voor boiler

kg CO2-eq per GJ

Netto CO2-eq emissie

Sugar cane, residue left residue burnt

reduction of SOM per ton saved CO2 emission

per sector

-100,0

-50,0

0,0

50,0

100,0

150,0

200,0

250,0

300,0

350,0

E+W Transport Chemie

afn

am

e B

OS (k

g)/

to

n v

erm

ed

en C

O2

Afname organische stof per ton vermeden CO2-eq

Croezen, Odegard, Bergsma & Langeveld, Soil in the Bio-economy ( in Dutch), publ nr 13.2813.19, 2013, CE-Delft

Concluding remarks

Healthy soil requires sufficient SOM Maintenance of SOM requires sufficient

plant residue input Sustainable bio-based economy requires

sufficient care about SOM

Acknowledgement

Advisors: Geert Bergsma, CE Delft, NL Kor Zwart, Alterra, Wageningen, NL Peter Kuikman, Alterra, Wageningen, NL

Sponsors: BE-Basic, Delft, NL NIOO-KNAW, Wageningen, NL

soil erosion

http://soils.usda.gov/sqi/concepts/soil_organic_matter/som_manage.html

Effects of a BIOBASED Economy

• More biomass needed for:

– Food

– Fuel

– Fossil fuel based products

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

Biobased Energy

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

Biobased Energy

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

Source: EEA, (2006)

Effects BBE on soil

• Less crop residues return directly to the soil

• Less biomass available for composting

• Further processing of animal manure to extract more energy: less organic matter return to the soils

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati

Functions SOM

http://grdc.com.au/uploads/documents/cso000291.pdf

Zwart & Kuikman ASA, CSSA, ASSA meeting 2012, Cincinnati