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| Titel |
Incorporation and measurement of synthetic nanosized iron oxides into soil profile for innovative agricultural applications |
| VerfasserIn |
G. Guzman, J. C. Cañasveras, V. Barron, J. A. Gómez |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250062004
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| Zusammenfassung |
| Iron oxides are natural constituents of soils providing them different characteristics. That
differentiation has been used as in fingerprinting studies to determine sources of sediment,
especially at large scales. However, there is a lack of studies that use this approach at
smaller scales using iron oxides differences because these differences, among zones,
are difficult to establish. The incorporation to soil profile of synthetic nanosized
iron oxides could increase and improve the detection of differences in iron oxide
properties among zones at plot or hillslope scales, solving problems that arise when that
objective have been pursued with magnetic tracers of millimeter scale (Ventura et al.
2002).
Magnetite (Fe3O4), hematite (α-Fe2O3) and goethite (FeOOH) can be commercially
available as Bayferrox® 318M, 110 and 920 respectively, and traditionally used as pigments.
Because of their properties, these iron oxides could fulfill all the requirements, defined by
Zhang et al. 2001, for being sediment tracers.
This communication describes the whole process of incorporation into the soil profile and
the determination of the concentration of these iron oxides into the soil and in the transported
sediment in water erosion experiments, and their use to estimate soil losses, identifying
erosion and deposition areas, and quantifying the contribution to exported sediment of
different zones. Their characteristics allowed a relatively easy detection by measuring the
magnetic susceptibility, in the case of magnetite, and spectral properties by diffuse reflectance
spectroscopy for hematite and goethite. Laboratory and field magnetic measurement
techniques were set up considering bulk density variations at the soil samplings.
Hematite and goethite measurements were also calibrated for the study-site soil and for
different magnetite, hematite and goethite concentrations. A comparison of the
measured iron oxide concentrations and a multivariate mixing model (Rhoton et al.
2008), normally used in fingerprinting studies, was carried out obtaining promising
results.
The results indicates that synthetic nanosized iron oxides affords quick, nondestructive
and relatively inexpensive analysis and are useful tools as monitors of sediment
dynamics.
References:
Rhoton, F.E., Emmerich, W.E., DiCarlo, D.A., McChesney, D.S., Nearing, M.A., Ritchie,
J.C. 2008. Identification of suspended sediment sources using soil characteristics in a
semiarid watershed. Sci. Soc. Am. J. 72: 1102–1112.
Ventura, E., Nearing, M.A., Amore, E., Norton, L.D. 2002. The study of detachment and
deposition on a hillslope using a magnetic tracer. Catena 48: 149–161.
Zhang, X.C., Friedrich, J.M., Nearing, M.A., Norton, L.D. 2001. Potential use of rare
earth oxides as tracers for soil erosion and aggregation studies. Sci. Soc. Am. J.
65:
1508–1515. |
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