dc.contributor.advisor | Gerold, Gerhard Prof. Dr. | |
dc.contributor.author | Vianden, Mitja Johannes | |
dc.date.accessioned | 2013-10-08T10:10:46Z | |
dc.date.available | 2013-10-08T10:10:46Z | |
dc.date.issued | 2013-10-08 | |
dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-0001-BBD1-B | |
dc.identifier.uri | http://dx.doi.org/10.53846/goediss-4085 | |
dc.language.iso | deu | de |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/3.0/ | |
dc.subject.ddc | 910 | de |
dc.subject.ddc | 550 | de |
dc.title | Zerstörungsfreie Wurzelortung mit geophysikalischen Methoden im urbanen Raum | de |
dc.type | doctoralThesis | de |
dc.title.translated | Non-destructive detection of tree roots with geophysical methods in urban areas | de |
dc.contributor.referee | Gerold, Gerhard Prof. Dr. | |
dc.date.examination | 2013-07-25 | |
dc.description.abstracteng | The aim of the work was to analyse whether Ground Penetrating Radar (GPR)
and Electrical Resistivity Tomography (ERT) are suitable to detect tree
roots in urban areas.
The non-destructive visualisation of roots was conducted for scientific as
well as for applied reasons. On the one hand information about the root
distribution derived from imaging techniques can be used to interpret
ecological cycles. On the other hand this information is available to
protect the subsurface part of urban trees during underground construction
activities.
The work consists of three parts including 2D-measurements under
controlled conditions, fundamental analysis for 3D-measurements and the
3D-investigation of several urban tree sites. The main focus of the work
was on GPR because of the high resolution of this method.
The 2D-measurements in the lysimeter-basins in the New Botanical Garden in
Göttingen have shown that tree roots with a minimal diameter of 3 cm can
be detected with a 400-MHz-antenna.
Furthermore a new approach for the determination of root diameter in
2D-GPR measurements based on multiple reflections was used. From another
experiment comparing tree roots to other typical subsurface objects (like
cables) it could be concluded that 3D-measurements are not only necessary
to locate single roots but also to differentiate roots and other objects
by their position and angle in the soil.
A methodological improvement compared to the work of other authors could
be achieved by the application of a dense measurement grid with a transect
separation of 15 cm. The results have been verified by excavations of tree
roots.
Comparing different urban tree sites the best results have been achieved
on homogeneous, near-natural park areas where the root systems have been
reconstructed by the results of the GPR-measurements. In contrast, sites
with a high portion of coarse fragments are not suitable for root
detection with GPR because the reflections of the coarse fragments overlay
the reflections of the tree roots and mask them in the results.
Another difficulty is the visualisation of roots growing downwards.
This can be explained by the overlaying of these roots by stronger
reflections from other depth when bigger depth ranges are projected in one
horizontal slice.
On some investigated sites the GPR measurements have been supplemented by
geoelectrical surveys. Here, the statistical correlation between the
specific electrical resistivity and the root mass in the underground
reported by other authors could not be confirmed. | de |
dc.contributor.coReferee | Rust, Steffen Prof. Dr. | |
dc.subject.ger | Bodenradar | de |
dc.subject.ger | Elektrische Widerstandstomographie | de |
dc.subject.ger | Baumwurzeln | de |
dc.subject.ger | Stadtbäume | de |
dc.subject.ger | Zerstörungsfreie Ortung | de |
dc.subject.ger | Wurzelsystem | de |
dc.subject.eng | GPR | de |
dc.subject.eng | tree roots | de |
dc.subject.eng | ERT | de |
dc.subject.eng | electrical resistivity tomography | de |
dc.subject.eng | ground penetrating radar | de |
dc.subject.eng | non-destructive detection | de |
dc.subject.eng | urban trees | de |
dc.subject.eng | root system | de |
dc.identifier.urn | urn:nbn:de:gbv:7-11858/00-1735-0000-0001-BBD1-B-3 | |
dc.affiliation.institute | Fakultät für Geowissenschaften und Geographie | de |
dc.subject.gokfull | Geographie (PPN621264008) | de |
dc.identifier.ppn | 769480748 | |