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| Titel |
Selected soil physical and hydraulic properties for different crop successions under no tillage |
| VerfasserIn |
M. C. Sasal, M. Castiglioni, J. Paz-Ferreiro, M. G. Wilson, J. Oszust |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250030889
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| Zusammenfassung |
| No tillage is now widely widespread in Argentina in response to several circumstances,
including limited runoff and a drop in soil erosion. Crop residues left on the soil surface help
both natural rainfall and irrigation water infiltrate and also limits evaporation, conserving
water for plant growth. This notwithstanding, wide differences in runoff rates between crop
succession have been observed under no tillage. The aim of this work was to assess the effect
of the main crop successions of Entre Ríos province, Argentina on selected soil physic and
hydraulic properties. Results obtained on no-till plots were compared with those recorded on
a 10-years old grassland plot and on a conventionally tilled plot left bare, both of them taken
as references. The study soil was classified as an Aquic Argiudoll. Treatments were:
maize and soybean, both cropped as monoculture, succession wheat/soybean or
wheat/maize, grassland and conventionally tilled soil left bare. Soil runoff was
recorded on experimental plots 100 m2 in surface. Saturated hydraulic conductivity
(Khc) and sorptivity were measured in field conditions using a disc permeameter.
Bulk density (Bd), saturated hydraulic conductivity (Kh) total porosity (TP) and
pore size distributions were determined on undisturbed cores sampled at the 0-4
and 4-8 cm depth with five replications. Maximum water losses were recorded
in bare soils conventionally tilled. Under maize and soybean monocultures water
losses were six time higher than under grassland. Water losses under successions
wheat/soybean-maize were lower than under monoculture but not significantly
different. Field saturated hydraulic conductivity (Khc) was highest under grassland
and the remaining treatments don’t showed significant differences. Differences in
sorptivity between plots were not significantly different. A significant relationship
was found between saturated hydraulic conductivity measured in field conditions
(Khc) and determined in soil cores (Kh) and on average the later was 2.5 times
higher than the former. Soil pore space with diameters >50 μm was higher under
grassland at both sampling depths and showed no significant differences between
other treatments. Saturated hydraulic conductivity (Khc), TP and Bd showed a
significant relationship at the 0-4 cm depth. Runoff variance was explained by TP and
partial porosity |
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