Scientific and Research Projects

• High Frequency Densitometry („HF-Densitometry“): Method for high resolution measurements of wood density and its variation.
  Description of the project:

  Wood density (or specific gravity) largely determines the value and mechanical properties of wood and is therefore of key importance in wood research. Knowledge of wood density also allows determination of woody biomass in trees, stands and forests (and thus determination of carbon storage and carbon sequestration in forest ecosystems). As a tree grows environmental influences affect not only the width of year rings but also the density of the wood formed at a certain time. High resolution measurements of density and its variation tree stems (radial and vertical density profiles) can therefore be helpful for climate reconstructions. There are several methods for determining wood density, of which X-ray densitometry has become the standard technique if high resolution is needed. The innovative method of high frequency densitometry (“HF-densitometry”) that has been developed at the Institute for Forest Growth can be regarded as a feasible and easy to handle alternative to this reliable but laborious and expensive method. HF-densitometry uses the electric stray field of a dielectric dispersed slit probe that scans the surface of a wood sample. Because of the linear relation between the density and the dielectric permittivity of wood the obtained voltage signal can directly be converted to density readings once the respective probe has been calibrated. In this project HF-densitometry is being refined and probes with different resolution abilities are being developed and calibrated.
  
  contact person: Dr. Martin Schinker
  Email: Martin@schinkerei.de

  Runtime:

  Start of project: 1992
  End of project: (unlimited)

  Project Management:

  Albert-Ludwigs-University Freiburg
  Dr. Martin Schinker, Marc Wassenberg, Prof. Dr. Dr. h.c. Heinrich Spiecker