Presented by Katarina Hedlund at the seminar Save our Soils on May 20, Malmö, Sweden. Read more here: http://www.siani.se/event/SOSsoil

1. How different agricultural
practices affect soil health
KATARINA HEDLUND LUND UNIVERSITY

2. Agriculture and soil threats
Decline in: Lead to:
soil carbon soil erosion
biological activity soil compaction
soil biodiversity reduced
resistance to
pests
reduced nutrient
provisioning
Intensification
of agriculture

3. Soil ”health” - ecosystem services
Intermediate
ecosystem
services
Nutrient retention
Carbon storage
Water retention
Resistance to pests
Regulation of above
ground diversity
Final
ecosystem
services
Food
Feed
Biofuel
Clean water
Climate
mitigation
Soil biodiversity
Actions and inter-
actions among soil
organisms
feeding
digging burrows
mycorrhiza

4. Agriculture and ecosystem services
Foley et al Science 2005

5. Long term decline of soil-C in Europe
Brady et al 2015 Agronomy Journal

6. How can we change Soil C ?
Management C decline per year
Intensive cereal production -1.0% UK
Inorganic fertilisers -0.5% SE
Farm yard manure (5 ton/ha) -0.2% SE
Straw addition (3 ton/ha) -0.2% DK
Management C increase per year
Cover crops 0.2% FR
Straw addition (12 ton/ha) 0.3% DK
Farm yard manure (35 ton/ha) 0.4% UK
Ley 2 yrs (in 8 yr rotation) 0.3% SE
Miscanthus grass 2.0% US

7. Soil carbon and agriculture in Europe?
SOC in agricultural land 2009 Wheat yield
g/kg 100 kg/ha

8. Soil carbon and management
• Systematic Rewiew (Global scope)
– Soil carbon and agricultural management
– 25000 publications
– 750 papers used in review
• Management
– Tillage
– Amendents
– Fertilsers
– Crop rotations
http://www.eviem.se/en/projects/Soil-organic-carbon-stocks/

9. Systematic map
– review of global evidence
25000 papers checked
750 in the database to be used in meta-analyses

10. Systematic map – review of evidence
Interactive map – with metadata and links
to published evidence
Open access during 2015

11. Soilservice project
Soil management across EU
SwedenGreece

12. Soil carbon and biodiversity
Gradient of intensive crop rotation to pastures
Tsiafouli et al Global Change Biology 2014

13. Producers of ecosystem services
The soil food web

14. Food web diversity
Lower food
chain length
 Steeper
biomass
pyramid
 Lower C & N
mineralization
rates
Loss of
larger species
low intensity
high intensity

15. Greenhouse gas emissions
De Vries et al PNAS 2013

16. Nutrient retention
0
5
10
15
20
25
30
35
40
Pasture Extensive
rotation
Intensive
rotation
LeachedN(mg/l)
CZ
GR
SE
UK
0.0
2.0
4.0
6.0
8.0
10.0
Pasture Extensive
rotation
Intensive
rotation
AMfungalbiomass
CZ
GR
SE
UK
De Vries et al PNAS 2013

17. Soil biodiversity & intensive agriculture
• Reduce species diversity
• Lower food chain length
• Soil carbon: 10 – 0.8 %C
• Soil nitrogen: 0.4 - 0.1%N
• Specific groups that are influenced:
– AM fungi, earthworms, larger predatory mites
Pastures to crop rotation:

18. Smart management decisions?
Support ecosystem services
Nutrient
retention
Food
Fiber
Water
regulation
Natural pest
controlCarbon
retention
Soil
formation
Climate
regulation
Nutrient
retention
Food
Fiber
Water regulation
Natural pest
controlCarbon
retention
Soil
formation
Climate
regulation

19. Using ecosystem services for decisions
Ecosystems &
biodiversity
Ecosystem
services
Decisions
Institutions
(farmers, EC)
Values
Agricultural
management
Information
on sustainable
soil use
Incentives
After Daily et al 2009
”decision loop”
Valuation
models
Mapping
services

20. Information transfer

21. "Natural Capital” - The ecosystem services from
nature which are essential for human life.
http://bankofnaturalcapital.com/category/ecosystem-services/agriculture/

22. Value of soil ecosystem services
Value to farmers
• Fertile soils
• Water retention
• Less erosion
• Less use of
– fertilizers
– pesticides
Value to society
• Reduce eutrofication
• Clean water
• Carbon retention
€?

23. Economic valuation:
Carbon a currency for natural capital
Brady et al 2015 Agronomy Journal

24. Optimal use of soil C
3
5
7
9
11
0.75 1.25 1.75 2.25 2.75 3.25
Yieldt/ha
% soil Carbon
Sweden Denmark
England Germany
0
50
100
150
200
0.75 1.25 1.75 2.25 2.75 3.25
Nitrogenkg/ha
% soil Carbon
Sweden Denmark England Germany
Optimal yield Optimal fertiliser use

25. Carbon a natural capital
200
400
600
800
1000
1200
1400
1600
1800
0.75 1.25 1.75 2.25 2.75 3.25
Maximumprofit€/ha
% soil Carbon
Sweden Denmark England Germany

26. 400
450
500
550
€/ha
2008 2012 2016 2020 2024 2028 2032
year
Sweden
250
300
350
400
€/ha
2008 2012 2016 2020 2024 2028 2032
year
UK
Ley in the crop rotation
Profit per hectare
40
42
44
46
48
50
52
2008 2012 2016 2020 2024 2028 2032 2008 2012 2016 2020 2024 2028 2032
Sweden UK
0% set aside 7% 15% 25%
kgwheat/kgN
year
Graphs by region
N-efficiency
Saarbacher et al in prep /SOILSERVICE project

27. Soil natural capital
• Promoting soil C means increasing soil
biodiversity and soil ecosystem services
• Processes are long term and yields will be
affected in the future
• The value of soil natural capital can be used
to promote sustainable management
• Soil C- investment banks?

29. 0
1000
2000
3000
4000
5000
6000
7000
8000
9000
1960 1980 2000 2020
kg/ha
Year
Wheat Scania Sweden
Yield increase and soils?

30. Filling yield gaps (wheat) with natural capital
(20 years)
Business as usual 0.3% SOC/yr increase rate
100kg/ha
Nelson E, Brady M, Hedlund K in prep

31. Tools for valuation of services
– project with Swedish EPA
Local level: C bank (open access tool)
Production model where yield is related to fertiliser
and ecosystem service levels
Regional level (Skåne): AgriPoliS “Agricultural Policy
Simulator”
Agent based model, optimise farmers profit and
predict land use within 25 years future
National level: Cost benefit analys of policy
Evaluate decisions and incentives to reach
environmental objectives