1) Soil erosion is an environmental issue addressed by Swiss policy, which aims to maintain long-term soil fertility. The Soil Pollution Ordinance sets guide values for erosion and requires appropriate cultivation techniques to prevent compaction and erosion. 2) Long-term monitoring in Frienisberg, Switzerland showed that total soil loss decreased from 200 tonnes/year in 1997-2007 to 59 tonnes/year in 2007-2016, corresponding to a reduction in conventional tillage and increase in conservation agriculture techniques. 3) Challenges in implementing the Soil Pollution Ordinance include inconsistent policies due to political negotiations, lack of resources in environmental administration, and viewing soil degradation as primarily an ag

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2. Soil erosion policy
in Switzerland
Gudrun Schwilch – FOEN & CDE Uni Bern
Corsin Lang - FOEN
Michael Zimmermann - FOAG
Volker Prasuhn - Agroscope
Nicolas Derungs – sanu durabilitas
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3. Mixed crop-livestock farming systems
in the hilly Swiss Midlands
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G. Schwilch
G. Schwilch
G. Schwilch
G. Schwilch

4. Sheet, rill and ephemeral gully erosion
V. Prasuhn
Potatoes
V. Prasuhn
Winter wheat seedbed
V. Prasuhn
Potatoes harvested
V. Prasuhn
Winter fallow after sugar beet

5. V. Prasuhn
Sources and triggers of soil erosion
V. Prasuhn
headlands, furrows…
slope depression, thalweg…
wheel tracks
V. Prasuhn
V. Prasuhn

6. Off-site damages on private and
public infrastructure
Sediment load in streams
T. Ledermann M. Brünisholz
V. Prasuhn
Off-site damage in
downstream field
Impacts of soil erosion
T. Ledermann
On-site damage

7. Swiss environmental policy system
• Environmental Protection Act (EPA)
• Soil Pollution Ordinance (SoilPO)
• Aim: long-term maintenance of soil fertility
• Implementation and monitoring = task of the cantons
• Evaluation of impact on the basis of the guide, trigger
and remediation values laid down in the annexes
• Prevention of compaction and erosion: person
exploiting the soil shall ensure appropriate cultivation
techniques, rotation and adaptation of crop cultivation.
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8. Guide values for erosion
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Annex 3
(Art. 5 Para. 1 and 6 Para. 2)
Guide values for erosion on arable land
1 Guide values
Depth through which roots can penetrate Total mean erosion1
(in tonnes dm per hectare and year)
Up to 70 cm 2
More than 70 cm 4
dm = dry matter
1 total mean erosion = sum of the sheet erosion and linear erosion

9. Swiss agricultural policy system
• complex system of direct payments (subsidies) to
compensate farmers for the different types of
services they deliver to the society (e.g. food
security, landscape protection, etc.).
• supports prevention of soil erosion indirectly, e.g.
by defining a minimal crop rotation or an optimal
soil coverage
• financial support is given to farmers applying
conservation tillage.
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10. Implementation guide
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SoilPO:
Art. 4 Monitoring of impact on the soil by the
cantons
2FOEN, in collaboration with FOAG, shall arrange to
provide the technical bases necessary for
monitoring the impact on the soil and shall advise
the cantons.
Soil protection in
agriculture

11. http://map.geo.admin.ch
Potential soil erosion risk of the agricultural area
Erosion risk map cropland Erosion risk map grassland
(Source: Schmidt et al, 2019)

12. Long term monitoring in Frienisberg, Canton of Bern:
comparison of total soil loss 1997-2007 and 2007-2016
(Source: Schelbert 2016)
265-hectare study area

13. 0.00
0.20
0.40
0.60
0.80
1.00
1.20
0
200
400
600
800
1000
1200
1400
soilloss(tha-1yr-1)
soilloss(t10yr-1)
soil loss (t 10 yr-1)
soil loss (t ha-1yr-1)
Relationship between soil tillage method and soil loss as
aggregate of 10 years (bars) and on a hectare basis (squares)
Plough
56%
Reduced
tillage
25%
Mulch
tillage
6%
No-till
13% Data: V. Prasuhn, Agroscope

14. Development of annual soil erosion over 20 years
Reduction of soil erosion from 200 t/year to 59 t/year
(Quelle: Prasuhn 2017)
Period 1 Period 2
265-hectarestudyarea
Data: V. Prasuhn, Agroscope

15. Agricultural fields (ha) with conservation agriculture
Data: R. Schwarz 2018, Fachstelle Bodenschutz Bern
Programme LKV 1996-2009, FPB 2010-15, REB 2014-17, Lobsigen, Seedorf, Suberg, Wiler, Schüpfen
Massive increase due to cantonal (2010-2015) and state subsidy
programmes (2014-2017)

16. Field trial in Frienisberg
The effect of the Dyker on infiltration, soil erosion, and waterlogging on
conventionally farmed potato fields in the Swiss Plateau
Potato planter with Dyker
without Dyker with Dyker
T. Lemann T. Lemann
17 June 2016 Precipitation 7 May – 17 June total 252 mm, max. 30.6 mm/24h
with Dyker
with Dyker
with Dyker
with Dyker
without Dyker
without Dyker
Waterlogging T. Lemann
T. Lemann

17. New enforcement (since 2017)
• Payments are cut for farmers who experience
recurrent soil erosion and do not cope by
developing a site-specific action plan and taking
adequate prevention measures.
• Cantonal administration: risk-based erosion
controls
• Action plan: for 6 years, includes concrete
measures for each field
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18. Problems implementing SoilPO
• top-down expert-based approach: reduced to an
agronomic on-site problem, left to technical experts
• the process of defining / negotiating agro-environmental
policies led to significant inconsistencies
• lack of human, financial, political and cognitive resources
in environmental administration and resistance with
respect to sustainable management measures
• ”silo effect”/ “sectoral logic” in the public administration
• points of consensus reached after long negotiations are
constantly being called into question, sending confusing
signals to all actors involved.
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19. Stakeholder involvement Frienisberg
G. Schwilch
HP. Liniger
HP. Liniger
G. Schwilch
Ecosystem services to communicate and
negotiate benefits, synergies and trade-
offs

20. Conclusions
• Long-term monitoring in the field made it possible to
draw conclusions with regard to extent, causes, spatial
distribution, and off-site damage of soil erosion as well
as the efficiency of mitigation measures.
• The approach taken in Switzerland may serve as input
for similar considerations in other countries. However,
experiences from the new enforcement are still lacking.
• The environmental problem of soil degradation is not
so much a technical as an expert, social, political and
democratic problem.
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