 |
| Titel |
Dual-continuum modeling of a natural tracer transport in a soil profile |
| VerfasserIn |
J. Dusek, M. Šanda, M. Dohnal, T. Vogel, M. Cislerova |
| Konferenz |
EGU General Assembly 2009
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250026434
|
|
|
|
|
|
| Zusammenfassung |
| This study aims at evaluation of soil water dynamics in a shallow hillslope soil. The
transport of stable oxygen isotope 18O in a variably saturated soil profile is simulated
by means of a one-dimensional dual-continuum model. The model is based on
Richards’ equation for the water flow and advection-dispersion equation for the isotope
transport. The isotope plays the role of a natural tracer. The detailed observation
of the isotope concentration has been carried out in a small headwater catchment
Uhlirska (Czech Republic) The concentration of 18O in soil water and subsurface
stormflow is analyzed and further used for the comparison with the model results.
Several vegetation seasons were analyzed with respect to both soil water fluxes and
isotope concentration variations. The parameters of the dual-continuum model were
taken from previous soil water flow studies. No additional parameter calibration,
based on the observed isotope concentrations, was performed. In overall, close
agreement with the observed variables was achieved. In particular, the measured
subsurface stormflow is in a relatively good agreement with the simulated outflow
from the preferential flow domain and the observed 18O concentration in soil water
correlates well with the simulated matrix domain concentration. Mixing processes in
the soil profile caused the isotope dilution (even though the preferential transport
was considered), i.e. no rapid (unmixed) event-driven 18O outflow through the
preferential pathways occurred. The study helped us to improve our understanding of the
complex transport processes through the heterogeneous soil system. The results
confirm that preferential flow is a relevant transport process in the studied soil profile. |
|
|
|
|
|
|