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152 CHAPTER 4. AQUATIC SYSTEMS
Main activities Projects of the group are related either to questions of water resources or paleoclimate,
or both. Some projects are mainly applications of established methods, whereas others intend
to develop new methods and approaches.
The main goal of a project studying groundwater in the North China Plain is to obtain a noble gas
paleotemperature record from a formerly little studied part of the world (see section 4.1.1). However,
it also involves an investigation of the current recharge to the heavily exploited groundwater resources
of this semi-arid area. Preliminary results of this study showing a clear paleoclimatic signal are being
published in the framework of the IAEA isotope hydrology series [Kreuzer et al. , in press 2005].
Similarly, a project on groundwater in Egypt focusses on the renewal rate of these resources that are
used to sustain new agricultural developments outside the Nile Delta (see section 4.1.2). The study
clearly shows that the regional groundwater originates from the Nile water, but the renewal is very
slow. This project has been a cornerstone of the thesis of Hany El-Gamal [El-Gamal, 2005]. A paper
is in preparation.
Recharge rates and processes are also central to a project focussing on groundwater in the nearby
Odenwald region (see section 4.1.3). However, the main problem in this case is not the overexploitation
of the resource but the incomplete understanding of the connection between recharge in the mountains
and water levels in the valley, where large water works are operating. Progress in this project has
been and will again be reported at meetings of the hydrogeology section of the German Geological
Society [Friedrich et al. , 2004].
A new idea is to try and use microscopic water inclusions in speleothems (stalagmites and other
carbonate sinters) to extract noble gas concentrations and temperatures (see section 4.1.4). After
some preliminary studies in the form of diploma theses [Rice, 2004; Träumner, 2005], this issue is now
studied in the framework of a DFG research unit in collaboration with the Radiometry Group of the
”Heidelberger Akademie der Wissenschaften” (see section 5.1.8). The issue of the analysis of noble
gases on very small samples and in new archives is also central to the project of our Marie Curie
fellow Laszlo Palcsu (see section 4.1.5). However, the scope of this project is wider, trying to advance
our general understanding of the ways in which noble gases in different archives can help us to gain
paleoclimatic information.
Another area of research that is currently developed is the study of interactions between groundwater
and lakes, where a strong link between the two subgroups of the aquatic systems section becomes
apparent (see section 4.1.6). A just completed diploma thesis investigated and validated the use of
Radon as a tracer to study this interaction [Kluge, 2005].
Funding The China project is funded by the DFG and its Chinese counterpart NSFC. The speleothem
project is part of a DFG research unit (”Dated speleothems as archives of the paleo-environment”).
The Odenwald project is a collaboration with the ”Hessisches Landesamt für Umwelt und Geologie”
and the tracer analyses are funded by the State of Hessen. Hany El-Gamal was supported by a longterm
mission fellowship of the Egyptian government. Laszlo Palcsu is supported by a Marie Curie
EIF fellowship of the EU (project ”ADNOGAPALIN”).
Cooperations In the above mentioned projects we cooperate with other groups of the institute,
in particular with the carbon cycle group for stable isotope analyses on groundwaters and with the
radiometry group for the preparation of 14 C samples for AMS analysis as well as on the study of
fluid inclusions in speleothems. There exists also a cooperation with the ice and climate group on
the analysis of He isotopes in ice. Cooperations outside the institute include local project partners
in China, Egypt and Hessen. Furthermore, close links exist to the noble gas and AMS labs at ETH
Zurich, where some of our samples are analysed, as well as to the isotope hydrology group at the
University of Bern. Several links exist to scientists at the UFZ in Leipzig and Halle, and many new
national and international cooperations will be forged in the framework of the upcoming DFG research
unit.
The institutions of our main cooperation partners are listed in the following (with shortcuts as used
for author affiliations in the project reports):
Institute of Hydrogeology and Environmental Geology, Chinese academy of geological sciences, Zhengding,
China (IHEG),
Geology Department, Faculty of Science, Minufiya University, Shebin El-Kom, Egypt (MINUF),
Hessisches Landesamt für Umwelt und Geologie, Wiesbaden, Germany (HLUG),
Institut für Isotopengeologie und Mineralische Rohstoffe, ETH Zürich, Switzerland (ETHZ).