Soil compaction - new field trials in DK
Specialist Adviser
Janne Aalborg
Nielsen
Cooporation
Aarhus University, University of Copenhagen
and Knowledge Centre for Agriculture
Aarhus University - soil physics
University of Copenhagen - plant physiology
The Knowledge Centre for Agriculture - project
leader and responsible for the treatments in the
trials
Why these trials?
Does heavy traffic in the field influence the
yield?
Loamy
sand (1012% clay)
Loam
(15-18%
clay)
Sandy
loam (1317% clay)
Treatments
Wet conditions - early spring
Trt. 1: No compaction
Trt. 2: Slurry trailer. 8-9 tonnes wheel load once
Trt. 3: Slurry trailer. 3 tonnes wheel load
once a year for 3-4 years
Trt. 4: Slurry trailer. 6 tonnes wheel load
once a year for 3-4 years
Trt. 5: Slurry trailer. 8-9 tonnes wheel load
once a year for 3-4 years
{Trt. 6 (only in Funen): 11-12 tonnes wheel load
(Vervaet slurry tanker) once a year 3-4 years}
Samson PG25 slurry trailer
Vervaet slurry tanker
Vertical stress and subsoil stress
Refleksion
Plant physiology
- some results from the first year
Some results from the first year….
Stress in the contact area between wheels and soil
6 t, 2.8 bar – (reach 3.8 bar)
Foto: Per Schjønning, AU-DJF
Some results from the first year….
Effect in the subsoil, three layers.
”Almost without mitigation down to 30 cm”.
90 cm~90-100 kPa
”50~50”
Wheel loads and
yields 2010,
Spring Barley
1
2
3
4
5
6
LSD
No compaction
Slurry trailer. 8-9
tonnes wheel load
once
Slurry trailer. 3 tonnes
wheel load once a
year for 3-4 years
Slurry trailer. 6 tonnes
wheel load once a
year for 3-4 years
Slurry trailer. 8-9
tonnes wheel load
once a year for 3-4
years
Trt. 6 (only Aarslev):
11-12 tonnes wheel
load (Vervaet slurry
tanker) for 3-4 years
Yield and
increased yield
dt per ha
Yield and increased yield
dt per ha
KU LIFE
DJF Årslev
DJF Flakkebjerg
Average, three trials
65.6
58
55.7
59.8
-
-4.7
-9.0
-
-8.8
-2.9
-4.5
-5.4
-15.5
-6.6
-11.4
-11.2
-10.1
-10
-8.8
-9.6
-
-3.9
-
-
7.6
ns
6.6
4.5
The first year showed that…
Traffic with heavy loaded wheels give a
decrease in the yield – probably this decrease is
caused by compaction and pugging of the
surface soil
The peak load in the contact area between
wheel and soil is one bar higher than the tyre
pressure
The high peak loads in the contact area reaches
the depth of 30 cm’s – almost without mitigation
The soil is also highly impacted all the way down
to 90 cm’s
Results - continued
Traffic with high loads causes high deformity of
the soil in the plough layer
In the plots with high wheel loads there are a
decrease in the amount of the plant parts above
soil surface
There are a tendency of less evaporation in
leafs from the plots with high wheel loads
Thank You ☺