% 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”.

@INPROCEEDINGS{Haegel:139468,
      author       = {Haegel, Franz-Hubert and Esser, Odilia and Jablonowski,
                      Nicolai David and Zimmermann, Egon and Mukherjee, Santanu
                      and Linden, A. and Huisman, Johan Alexander and Vereecken,
                      Harry},
      title        = {{C}haracterization, monitoring and imaging of biochar by
                      geoelectrical measurements},
      reportid     = {FZJ-2013-05457},
      year         = {2013},
      abstract     = {Although biochar has been intensively investigated in
                      recent years, thereis still a lack of knowledge due to the
                      variability of soil and biochar properties, and the wide
                      variety of experimentalconditions used in these
                      investigations. The properties of biochar strongly vary
                      depending on the feed materialand the production process.
                      Therefore, it is of great interest to have methods which
                      allow the characterization andlong-term in-situ monitoring
                      of biochar properties at different scales ranging from small
                      laboratory columns to fieldsites. In this study,
                      measurements on the complex electrical conductivity have
                      been performed by spectral inducedpolarization (SIP). The
                      method has been found to be a valuable tool for
                      distinguishing different types of biocharand for monitoring
                      the release of ions from biochar. SIP uses sinusoidal
                      alternative current in the frequency rangebetween 1 mHz and
                      45 kHz and provides information on the ohmic conductivity
                      and on the electrical polarizationof soil materials with
                      added biochars. Whereas the release of ions leads to an
                      increase of the ohmic conductivity,information on the
                      chemical structure of biochars can be obtained from the
                      polarization. Five types of biochar havebeen investigated in
                      this study. The magnitude and the frequency dependence of
                      the polarization can be used todistinguish the different
                      types of biochar. Biochars with a larger degree of
                      carbonization showed higher electronicconductivity and
                      yielded higher polarization. The frequency dependence of the
                      polarization further depended onthe amount and the size of
                      the biochar particles. The measurements also confirmed that
                      the release of ions frombiochar can be monitored using the
                      ohmic conductivity. Whereas SIP is suitable for the
                      characterization of biocharin the laboratory, electrical
                      impedance tomography (EIT) can be used to obtain the spatial
                      distribution of the complexelectrical conductivity in
                      laboratory columns and in the field. This method is an
                      imaging technique based onthe determination of SIP signals
                      with a larger set of electrode positions. It opens up
                      promising research avenuesfor in-situ monitoring of biochar
                      in field soils.},
      month         = {Apr},
      date          = {2013-04-07},
      organization  = {European Geosciences Union General
                       Assembly 2013, Vienna (Austria), 7 Apr
                       2013 - 12 Apr 2013},
      subtyp        = {Other},
      cin          = {IBG-3 / IBG-2 / ZEA-2},
      cid          = {I:(DE-Juel1)IBG-3-20101118 / I:(DE-Juel1)IBG-2-20101118 /
                      I:(DE-Juel1)ZEA-2-20090406},
      pnm          = {246 - Modelling and Monitoring Terrestrial Systems: Methods
                      and Technologies (POF2-246)},
      pid          = {G:(DE-HGF)POF2-246},
      typ          = {PUB:(DE-HGF)24},
      url          = {https://juser.fz-juelich.de/record/139468},
}