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| Titel |
Microbiological assessment of the application of quicklime and limestone as a measure to stabilize the structure of compaction-prone soils |
| VerfasserIn |
Evi Deltedesco, Lisa-Maria Bauer, Hans Unterfrauner, Robert Peticzka, Franz Zehetner, Katharina Maria Keiblinger |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250094780
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| Publikation (Nr.) |
 EGU/EGU2014-10211.pdf |
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| Zusammenfassung |
| Compaction of soils is caused by increasing mechanization of agriculture and forestry,
construction of pipelines, surface mining and land recultivation. This results in degradation
of aggregate stability and a decrease of pore space, esp. of macropores. It further
impairs the water- and air permeability, and restricts the habitat of soil organisms.
A promising approach to stabilize the structure and improve the permeability of
soils is the addition of polyvalent ions like Ca2+ which can be added in form of
quicklime (CaO) and limestone (CaCO3). In this study, we conducted a greenhouse pot
experiment using these two different sources of calcium ions in order to evaluate
their effect over time on physical properties and soil microbiology. We sampled
silty and clayey soils from three different locations in Austria and incubated them
with and without the liming materials (application 12.5 g) for 3 months in four
replicates.
In order to assess short-term and medium-term effects, soil samples were taken 2 days, 1
month and 3 months after application of quicklime and limestone, respectively. For these
samples, we determined pH, bulk density, aggregate stability and water retention
characteristics. Further, we measured microbiological parameters, such as potential enzyme
activities (cellulase, phosphatase, chitinase, protease, phenoloxidase and peroxidase activity),
PLFAs, microbial biomass carbon and nitrogen, dissolved organic carbon and nitrogen,
nitrate nitrogen and ammonium nitrogen.
In contrast to limestone, quicklime significantly improved soil aggregate stability in all
tested soils only 2 days after application. Initially, soil pH was strongly increased by
quicklime; however, after the second sampling (one month) the pH values of all tested soils
returned to levels comparable to the soils treated with limestone. Our preliminary
microbiological results show an immediate inhibition effect of quicklime on most potential
hydrolytic enzyme activities and an increase in oxidative enzyme activities. These effects
seem to be less pronounced in the medium term.
In summary our results indicate, that the application of quicklime is a feasible measure
for immediate stabilization of the structure of compaction-prone soils, showing only
short-term impact on most microbial parameters. |
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