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| Titel |
Effects of traffic-induced soil compaction on crop growth and soil properties |
| VerfasserIn |
Amélia Baibay, Lidong Ren, Tommy D'Hose, Jan De Pue, Greet Ruysschaert, Wim Cornelis |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250152587
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| Publikation (Nr.) |
 EGU/EGU2017-17440.pdf |
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| Zusammenfassung |
| Traffic-induced soil compaction on arable soils constitutes a major threat for agricultural
productivity and the environmental quality of the soil, water and atmosphere. The objective of
this work is to evaluate a set of prevention strategies for agricultural traffic under real
farming conditions. To that end, a one-pass traffic experiment was conducted near
Ghent, Belgium in winter 2015 on a sandy loam (haplic Luvisol; 43% sand, 47% silt,
10% clay). Winter rye (Secale cereale L.), which promotes the removal of residual
soil nitrogen and thus reduces the potential for nitrogen leaching, was sown as
cover crop using different tractor and weather settings on different field lanes: dry
(D, 0.16 m3 m−3) or wet (W, 0.20-0.23 m3 m−3) conditions, normal (N, 65 cm
width, axle load 8520 kg) or wide (W, 90 cm width, axle load 8520 kg) tires and
high (HP, 1.4 bars for N, 1.0 bar for W) or low (LP, 1.0 bar for N, 0.5 bar for W)
inflation pressure. Subsequently, crop biomass, root density and a set of hydrophysical
properties (penetration resistance, saturated hydraulic conductivity and water retention
at 15, 35 and 55 cm depth) were measured. Bulk density, soil quality indicators
(such as air capacity) and the pore size distribution were also calculated. Results
showed significant biomass reduction (p < 0.01) for trafficked plots compared to
their control (un-trafficked): 40% reduction under dry conditions and ∼80% under
wet conditions. However, no differences were found between traffic treatments.
A similar trend was observed for root density, though less significant. Under wet
conditions, the rooting depth was also reduced (10 cm instead of 30 cm), and densities
were very small. These results suggest a negative effect of compaction on crop
growth, worse under wet conditions, but the choice of tires did not prove to have
an effect. Observations on the hydrophysical properties were more mitigated, as
expected: distinct differences are primarily found under controlled lab conditions or
after several passes. Moreover, high moisture conditions could not be obtained for
the wet experiment, which never exceeded field capacity, conceived as threshold.
Nevertheless, penetration resistance profiles indicated a plough pan about 40 cm depth,
witness of previous agricultural operations on the field, and high values (3.5 to 4
MPa) were found in the subsoil too. Moreover, bulk densities were higher for all
treatments (up to 1.8 Mg m−3) compared to the controls (∼1.55 Mg m−3). Saturated
hydraulic conductivities were very small (<< 10 cm/d), especially for the treatments.
The dry treatment also showed better values than the wet ones at 15 cm. Water
retention curves tended to show decreased water content at low suctions for the
treatments (mainly at 15 cm), which could reflect on a reduction of macropores and their
continuity. Soil quality parameters also showed better values in the control plots. These
observations support an overall compacted state and loss of structural quality, though no
significant impact of the traffic experiment or prevention strategies could be drawn. |
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