% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@PHDTHESIS{Yu:907377,
author = {Yu, Yi},
title = {{S}equential and coupled inversion of time-lapse borehole
{GPR} measurements for vadose zone model parameterization},
volume = {565},
school = {Univ. Bonn},
type = {Dissertation},
address = {Jülich},
publisher = {Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag},
reportid = {FZJ-2022-01999},
isbn = {978-3-95806-607-6},
series = {Schriften des Forschungszentrums Jülich Reihe Energie $\&$
Umwelt / Energy $\&$ Environment},
pages = {XX, 121},
year = {2022},
note = {Dissertation, Univ. Bonn, 2021},
abstract = {A profound understanding of the infiltration dynamics into
the vadose zone is crucial to ourcapacity to link surface
and subsurface processes for the description of the
hydrologic cycle. Akey to establish reliable models
describing the infiltration process is the knowledge of the
soilhydraulic parameters. A promising approach to estimate
soil hydraulic parameters is inversemodeling based on
dynamic changes in soil water content (SWC). In this
context, groundpenetrating radar (GPR) has been recognized
as a powerful geophysical technique in vadose
zonehydrogeophysics, because SWC is strongly related to the
soil bulk permittivity that can beprecisely determined by
GPR. The aim of this thesis is to investigate the
feasibility of using timelapseGPR measurements obtained
during infiltration events for vadose zone
characterizationwith a special focus on the estimation of
soil hydraulic parameters.A prerequisite for estimating soil
hydraulic parameters based on GPR measurements
obtainedduring infiltration events is that the GPR
measurements should reliably reflect the transient
SWCdynamics during and after infiltration events. To verify
this, a 4-day infiltration experiment wasperformed at the
rhizotron facility in Selhausen, Germany. SWC information at
0.2, 0.4, 0.6, 0.8,and 1.2 m depths were obtained by
zero-offset profiling (ZOP) measurements from
horizontalborehole GPR. Unfortunately, SWC information for
the top 0.1 m of soil obtained by ZOPmeasurements was not
reliable due to the strong interference between direct and
refracted waves.To solve this problem, surface GPR
measurements were additionally conducted. Dispersiveguided
waves were observed in the 500 MHz surface GPR data because
the infiltration eventgenerated electromagnetic waveguides
in the top soil layer. This allowed to obtain SWCinformation
of the top 0.1 m soil layer through dispersion analysis of
the dispersive surface GPRdata. By combining surface and
horizontal borehole GPR measurements, the vertical
SWCprofiles (0 - 1.2 m) and dynamics were successfully
represented during and after infiltration
events.Additionally, it was found that the GPR-derived SWC
corresponded well with independentlymeasured SWC estimates
obtained with time domain reflectometry (TDR) and the known
amountof water applied in the infiltration events.},
cin = {IBG-3},
cid = {I:(DE-Juel1)IBG-3-20101118},
pnm = {2173 - Agro-biogeosystems: controls, feedbacks and impact
(POF4-217)},
pid = {G:(DE-HGF)POF4-2173},
typ = {PUB:(DE-HGF)3 / PUB:(DE-HGF)11},
urn = {urn:nbn:de:0001-2022051802},
url = {https://juser.fz-juelich.de/record/907377},
}