Cover crops for conservation agriculture CC4CA

Federal Department of Economic Affairs,
Education and Research EAER
Agroscope
Cover crops for conservation agriculture
(CC4CA): from research to
implementation in Switzerland
Raphaël CHARLES, Camille AMOSSÉ, Cindy BALLY, Lucie BÜCHI, Marina WENDLING
Agroscope, Institute for Plant Production Sciences, Field crop systems, Nyon,
Switzerland
CC4CA: from research to implementation
Raphaël Charles
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Agroscope research station in Changins
mean temperature: 10.2°C
annual rainfall: 999 mm
CC4CA: from research to implementation
Raphaël Charles
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From research to implementation
Innovation is in the hand of farmers - pioneers - particularly for the
development of conservation agriculture
Research is needed to
- provide scientific evidence for benefits and drawbacks
- bring scientific evidence to empirical knowledge
- explain successes and failures
To that purpose, we need
- LTE: soil tillage, organic fertilisation, crop rotation
- Specific trials: screening of cover crops, CC * soil tillage
- On farm experiments, demonstrations, platforms
CC4CA: from research to implementation
Raphaël Charles
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Challenges for Switzerland
X
Weed control
Glyphosate
Organic matter
Nitrogen availability
Conservation
Agriculture
C-N cycle
Organic matter
P cycle
Soil cover
Cover crops
New expected services
CC4CA: from research to implementation
Raphaël Charles
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Long term experiments
Worldwide population growth in relation to the development of farming
systems (Mazoyer & Roudard, 2002)
CC4CA: from research to implementation
Raphaël Charles
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LTE wheat in crop rotation and soil tillage 1967
Monoculture - minimum tillage
Monoculture - plough
Rotation - minimum tillage
Rotation - plough
Variance components
Part of the variance
(% MS)
Rotation
Soil tillage
Variety
Crop protection
Interactions
66 %
9%
13 %
2%
10 %
Charles et al., 2015
CC4CA: from research to implementation
Raphaël Charles
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LTE soil tillage 1969
sol argileux, 0-10 cm
CC4CA: from research to implementation
Raphaël Charles
Vullioud et al., 2004 et 2006
7
LTE Organic fertilizers 1975
100% = mineral fertilizer
Maltas et al., 2012
CC4CA: from research to implementation
Raphaël Charles
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Soil cover: modeling
Stubble, cover crop
Main crop
growth
decomposition
Soil cover
Soil tillage
senescence
6.
1 1.
2.
7.
5.
3.
4.
0
harvest
sowing emergence
residues
max cover
maturity harvest
crop
Soil cover for different crops
Büchi et al., submitted
CC4CA: from research to implementation
Raphaël Charles
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NFP68: Soil as a resource
Cover Crops for Conservation Agriculture - CC4CA
Dr. Bernhard Streit HAFL, Dr. Raphaël Charles AGS, Prof. Dr. Achim Walter ETHZ
Biomass
Photo: P. Hofer
Priority
objectives for
CC in CA
On farm trials
extension
services
Erosion
0
Nitrate
1
BNF
11
Weeds
15
Herbicides
6
Biofumigation
3
Soil structure
3
SOM
0
Soil biological
activity
0
Second crop
X
Mixture of species
Intercropping
Competition for resources
Allelopathy
Nutrient cycle
N Fixation
CC4CA: from research to implementation
10
3
Raphaël Charles
Biodiversity
1
Economy
0
N, P, K, Mg
CC4CA: from research to implementation
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CC diversity and services in CA
Nitrate
Design CC species
N fixation
Soil
chemical
properties
C sequestration
Rotation
CC species * soil tillage
Resilience
Cropping
system
Ressources
Air-water balance
Nutrients
Organic
matter
Erosion,
run-off,
crusting
Compaction
Cover
crops
Landscape
Soil
physical
properties
Weeds
Soil
life
Biological
properties
Pests,
diseases
Fauna, pollinators
Novel CC for CA
CC4CA: from research to implementation
Raphaël Charles
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Screening : Observations
Leaf
traits
40
60
Biomass
Nutrients
Soil cover
20
Soil cover
0
Canopy cover %
80
100
Roots
Emergence
CC4CA:
0 from research to implementation
20
40
60
Raphaël Charles
Days after sowing
80
100
13
Role of legumes as cover crops
Conditions of poor mineralisation
 N limiting
 SOM insufficient
 Minimum soil tillage
End of cover crop growth
Beginning leaching
N in biomass
kg N/ha
100
Nmin
without cover
Wheat
harvest
Mid
September
Begin
winter
CC4CA: from research to implementation
Raphaël Charles
Büchi et al., 2015
14
Cover crop in mixtures
Bi-specific mixtures
without interaction
with interaction
Complex mixtures : best performing associations according to modeling
Sp2
Sp3
Sp1
Kirwan et al., 2009
Sp4
CC4CA: from research to implementation
Raphaël Charles
Espèce 1
Espèce 2
Espèce 3
2010
0% oat
0% phacelia 40% Berseem cl. 60% pea
2011
25% oat
45% phacelia 15% Berseem cl. 15% pea
2012
0% oat
64% phacelia 36% com. vetch
2012
25% mustard 24% navette 0% com. vetch
50% pea
2013
100% oat
0% pea
0% phacelia 0% mustard
Espèce 4
0% pea
Wendling et al., 2014
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Nutrients accumulation
CC4CA: from research to implementation
Raphaël Charles
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Nutrients accumulation
N
P
phacelia
phacelia
sunflower
sunflower
Brassicaceae
Fabaceae
Poaceae
Asteraceae
Other family
Wendling et al., 2015
CC4CA: from research to implementation
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Root traits
Wendling et al., 2015
CC4CA: from research to implementation
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Weed control
CC4CA: from research to implementation
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Modification of
growth conditions
Competition for
resources
Cover crop biomass (dt/ha)
Soil cover by weeds (%)
Soil cover by weeds (%)
Mechanisms responsible for weed control
Number of days to cover 50% of soil
Charles et al., 2014
CC4CA: from research to implementation
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Mechanisms responsible for weed control
100 %
Forage pea
300 %
Soil cover by weeds [%]
35%
Biomass [t/ha]
20 %
Seed density [% of recommendation]
Soil cover by weeds [%]
Brown mustard
Biomass [t/ha]
Biomass [t/ha]
Soil cover by weeds [%]
Black oat
Seed density [% of recommendation]
Wendling et al., 2015
CC4CA: from research to implementation
Raphaël Charles
Seed density [% of recommendation]
21
Cover crops * soil tillage: study in a LTE
Plough 64 %
Minimum tillage 30 %
CC4CA: from research to implementation
Raphaël Charles
No-till 6 %
16’500 ha
B. Streit, 2010
22
Setting: long term experiment
Treatments
1. Deep inversion tillage (plough, 25-30 cm)
2. Deep non inversion tillage (chisel, 25-30 cm)
3. Shallow non inversion tillage (cultivator, 10-15 cm)
4. Minimum tillage (rotary harrow, 5-10 cm)
III
2
Rotation
winter wheat – maize –
winter wheat – winter rapeseed
III
1
2
1
3
4
1
4
2
3
2
1
II
IV
4
3
2
3
1
4
Soil
Clay
Silty
Clay
51 %
27 %
Silt
33 %
44 %
Sand
16 %
29 %
II
3
1
2
4
4
Silty soil
CC4CA: from research to implementation
Raphaël Charles
I
I
3
2
1
4
3
Clay soil
23
Setting: latest modification (2007)
Soil tillage treatments
1. Deep inversion tillage
2. Deep non inversion tillage => No till (last tillage in autumn 2006)
3. Shallow non inversion tillage
4. Minimum tillage
Rotation
=> introduction of cover crops to accompany the transition to no till
• before maize, after winter wheat,
• as subplots, before winter wheat
CC4CA: from research to implementation
Raphaël Charles
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Setting: cover crops
Aim: Nutrient accumulation by cover crops and influence on
the following crop
Short season cover crops before winter wheat (2013, 2014, 2015)
(Direct) seeding: beginning of August
Growth: 3 months
2
1
3
4
8 subplots:
- Brown mustard (Brassica juncea)
- Forage radish (Raphanus sativus longipinnatus)
- Field pea (Pisum sativum)
1
2
4
3
4
1
2
3
1
4
2
3
3
1
2
4
4
3
2
1
4
3
2
1
- Oat (Avena strigosa)
- Niger (Guizotia abyssinica)
- Phacelia (Phacelia tanacetifolia)
- 11 species mixture (50% legumes)
- non-seeded control
CC4CA: from research to implementation
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CC4CA: from research to implementation
Raphaël Charles
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Cover crop and wheat yield
cover crop dry yield (2013 / clay
wheat dry yield (2014 / clay soil)
Büchi et al., 2015
CC4CA: from research to implementation
Raphaël Charles
mixture
phacelia
niger
oat
field pea
radish
mustard
soil / all treatments together)
T1: deep inversion tillage
T2’: no till
T4: minimum tillage
27
Yield according to tillage
winter wheat / dry yield
T1: deep inversion tillage
(plough)
T2: deep non inversion tillage
(chisel) then no till
T4: minimum tillage (rotary
harrow)
Years after no till
1: 2009
2: 2011
3: 2013
Büchi et al., 2015
CC4CA: from research to implementation
Raphaël Charles
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Soil organic matter
clay soil
Depth [cm]
soil organic matter:
0-20 cm layer
Büchi et al., 2015
CC4CA: from research to implementation
Raphaël Charles
T1: deep inversion tillage
T2: deep non inversion tillage then T2’: no till
T4: minimum tillage
stratification:
2013 / clay soil
29
Implementation
CC4CA: from research to implementation
Raphaël Charles
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On farm trials and platforms
Test of different species under different pedoclimatic conditions
Priority
objectives for
CC in CA
On farm trials
extension
services
Erosion
0
Nitrate
1
BNF
11
Weeds
15
Herbicides
6
Biofumigation
3
Soil structure
3
SOM
0
Soil biological
activity
0
Second crop
3
Biodiversity
1
Economy
0
A. Chassot, 2010
CC4CA: from research to implementation
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Biomass before winter
PAG-CH, 2014
2011-12 to 2013-2014
31
Swiss No Till, local extension services
CC4CA: from research to implementation
Raphaël Charles
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Technical sheets
CC4CA: from research to implementation
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Justes E., Beaudoin N., Bertuzzi P., Charles R., Constantin J., Dürr C., Hermon C., Joannon A., Le
Bas C., Mary B., Mignolet C., Montfort F., Ruiz L., Sarthou J.P., Souchère V., Tournebize J., 2012.
Réduire les fuites de nitrate au moyen de cultures intermédiaires : conséquences sur les bilans
d’eau et d’azote, autres services écosystémiques. Rapport d'étude, INRA (France).
https://www6.paris.inra.fr/depe/Projets/Cultures-Intermediaires
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CC4CA: from research to implementation
Raphaël Charles
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