View of Jena representing the interdisciplinary Profile Lines LIGHT, LIFE, LIBERTY

Research Topics and Foci

Overview of research at the Chair of Hydrogeology
View of Jena representing the interdisciplinary Profile Lines LIGHT, LIFE, LIBERTY
Image: Thomas Ritschel

Research at the Chair of Hydrogeology

Hydrogeological research at the Friedrich Schiller University Jena focuses on a in-depth understanding of structure, dynamics and functioning of the part of the earth's crust, which forms under the influence of atmosphere, hydrosphere, biosphere and lithosphere and is termed the "Critical Zone". This also includes the unsaturated zone and the near-surface hydrogeosphere.

Fundamental research foci Expand entry
Column used for reactive and biological transport experiments Column used for reactive and biological transport experiments Image: Katharina Lehmann

The main motiv for our work is defined by process oriented research in natural and anthropogeneously influenced, biotic, heterogeneous systems on different scales. Objective is a in-depth mechanistic understanding of architecture, dynamics, and functioning of geo- and pedosystems. This requires elucidation of the complex interactions, antagonisms and synergisms of physical, chemical and biological processes, formulation of theories and description of the former in suitable mathematical modells. Progessively, it becomes apparent that the phenomenons on the continuums scale, for example the pedon of an arable or forestry parcel, are controlled and influenced by biochemical and biophysical processes and properties, which occur on the molecular and atomic scale. Therefore, it is one of the central challenges to mechanistically describe and quantitatively determine the extreme large scale transitions, which comprise 9 orders of magnitude in space (nanometres to metres) and up to 21 orders of magnitude in time (femtoseconds to gigaseconds).

To derive a "picture" of composition and structure, i.e. the "architecture" of natural porous media and their temporal variations is a crucial prerequiste. In our hydrogeological research here in Jena, we therefore attempt to create a "window" into the opaque subsurface - soil, unsaturated zone and aquifers. The combination of modern imaging, spectroscopic, microscopic and tomographic techniques with process oriented mathematical modeling and modeling of quantum-mechanical processes represents a promising approach, which allows to reconstruct the structure of natural porous media, reproduce their temporal dynamics and elucidate the interaction of structure and functioning. It repeatedly becomes clear that natural or synthetic, nanoparticulate or colloidal mixed phases play a central role, because they influence properties and functioning of natural porous media. This integrative experimental and theoretical approach is systematically explored in the fundamental research at the Chair of Hydrogeology in Jena in the framework of diverse projects with different project partners.

Current foci  of our research are:

  • Architecture, dynamics and funcitoning of biogeochemical interfaces: Understanding of process effects and quantification of scale transitions from atom to pedon. This research focus is the subject of a priority program, which is coordinated by the chair of hydrogeology in Jena (www.spp1315.uni-jena.de).
  • Mobility and persistence of dissolved, colloidal- and particulate dispersed particles and contaminants.
  • Organo-mineral nanoparticulate and colloidal mixed phases: Formation, characteristics and functioning
  • Structural dynamics of natural porous media
  • Characterization and mathematical description of the spatial heterogeneity on different scales and quantification of scale transitions
  • Formulation of models and numerical modeling of the coupled reactive transport in porous media in the presence of mobile sorbents
  • Formulation of models and simulation of the colloid-dependent fluid dynamics in porous systems
  • Formation, release, transport, transformation and immobilisation of natural organic matter in soils and aquifers
Applied research foci Expand entry
Groundwater sampling Groundwater sampling Image: Robert Lehmann

Furthermore, the Chair of Hydrogeology in Jena carries out projects in applied subjects considering geo- and pedopotentials of Thuringia and soil technology. Considering the prior, exploration, evaluation and utilization of soils and subsurface with respect to geothermal energy, storage of energy and matter and the natural attenuation potential of natural porous media is foregrounded. The latter aims for a systematical development of soil based techniques for problem solving in the area of preventive and remedial protection of groundwater and soil.


Techniques and methods for protection and remediation are being developed by selective amplification and optimization of natural processes and by the utilization and intellligent combination of soil materials and processes. Classical examples are constructed wetlands, piling, landfill covers, filters for gases and odors. Innovative and advanced concepts, which are being developed here in Jena are "intelligent area filters", which enable the retention and degradation of substances being introduced into soils directly or diffusively by anthropogeneous activities.

The subject of remediation techniques, particularly of soil technology, gains progressively more importance. Just thinking about the systematical destruction and contamination of soil resources and groundwater reservoirs in south america, the tiger economies, India and China, it becomes apparent that problems are on the  rise, which already have a direct influence on health and life expectation of humans. In China, these problems are already being recognized and counteraction will come into effect in the medium term. This will entail a demand for intelligent and economic protection and remediation techniques.

Applied research areas of the Chair of Hydrogeology at the Friedrich-Schiller-University Jena are:

  • Development of innovative remediation techniques
  • Development of "intelligent area filters"
  • Pedo-/Geopotentials of Thuringia
Hydrogeosphere and services provided by the Critical Zone Expand entry
Soil seepage Soil seepage Image: Katharina Lehmann

The uppermost region of the earth's crust, the "thin skin of the earth", is not only of crucial importance for the life-sustaining production of food and resources. It is also a central tie in the global cycles of information, matter and energy. For example, 25% of the atmospheric carbon originates from processes taking place in soils. Soils contain double the amount of carbon of the atmosphere and triple the amount of carbon contained in the entire vegetation. Yet, not only the global cycles are controlled by the "thin skin of the earth". They have a central function as buffer-, storage-, filter- and transformation medium for water and dissolved and particulate matter. The quality of drinking water, which originates to a large fraction from groundwater reservoirs, rivers and lakes, is decisively influenced by the properties of soils, unsaturated zone and aquifers through which it percolated. The safeguard and restoration of these, for our survival central functions, are  inseparately linked to an understanding of biogeochemical and biogeophysical processes and mechanisms, which are the basis of these functions.

Protection and Remediation of Soil and Groundwater Resources

Highly contaminated groundwater that is black due to iron sulfides Highly contaminated groundwater that is black due to iron sulfides Image: Robert Lehmann

Nearly 70% of german drinking water is groundwater. Its high quality results from the interplay of physical, chemical and biological processes in soils and aquifers. The fundament of the subsurface services "clean drinking water", "biodiversity" and "soil fertility" is provided by soil functions, which are increasingly threatened.

In particular, the change in climate and land use and the resulting excessive use of soil and groundwater resources is alarming. The protection and remediation of soils and groundwater is therefore one of the most important tasks at the chair of hydrogeology.

The protection focuses on the development of techniques to avoid and stop the spread of contaminations or to eliminate pollutants. The remediation focuses on the prevention of hazards and threats for human and ecosystem health. Therefore, techniques and methods are combines and newly developed to optimize and support natural physical, chemical and biological processes that attenuate the contamination.

Publications

Wehrer et al. (2011). Contaminants at Former Manufactured Gas Plants: Sources, Properties, and Processes. Crit. Rev. Environ. Sci. Technol. 41(21), 1883-1969.

Wehrer et al. (2013). Kinetic control of contaminant release from NAPLs – Experimental evidence. Environ. Pollut. 179, 315-325.

Projects

BMBF - Nanosan de

ReGround de

EU - SoilCAM

Thüringen/EU - Biogeothermie

EU - AQUATERRA

Formation and Alteration of Organo-Mineral Associations and Microaggregates

REM-EDX-Image of kaolinite booklets in sandstone REM-EDX-Image of kaolinite booklets in sandstone Image: Michaela Aehnelt

The association of diverse (a)biotic components by natural organic "glueing" agents results in a threedimensional arrangement of minerals, organic matter and void space. In the size of a dust particles, these are referred to as microaggregate that form from host rock and its interaction with climate and soil organisms.

Microaggregates are, maybe the most important, habitat for soil microorganisms and essential for the transformation and transport of water, nutrients, carbon as well as contaminants. Furthermore, microaggregates host the function of soils as filter, buffer and reservoir. The understanding of soils therefore requires an in-depth knowledge of aggregate formation and their properties.

Projects

SPP1315 BGI in Soil de

FOR2179 MADSoil de

SFB1076 AquaDiva de

Hydrogeology of the Aeration Zone

Fissure in limestone Fissure in limestone Image: Bernd Kohlhepp

The aeration zone, including perched aquifers and the fluctuation zone of phreatic groundwater, frequently exhibits large thicknesses in areas of high groundwater recharge.

In particular, sedimentary rocks host a diversity of minerals, void space architecture and weathering conditions that provide a mutlitude of habitats. The contribution of microbial communities to groundwater quality and element turnover is largely unknown in variably saturated regolith and rock of the aeration zone. Many monitoring programs and hydrogeological models neglects the infleucen of the aeration zone despite its large thickness and reservoir volume.

Projects

SFB1076 AquaDiva de

FOR2179 MADSoil de

FOR918 Carbon flow on belowground food webs de

Biogeochemical Cycles and Reactions at Biogeochemical interfaces

Silty intraclast in sandstone Silty intraclast in sandstone Image: Bernd Kohlhepp

Soils and rock comprise a multifunctional heterogeneous structure that is characterized by diverse biogeochemical interfaces. Our research focuses on an in-depth, mechanistic understanding of the interactions and processes that operate at biogeochemical interfaces.

The experimental equipment available at the chair of hydrogologie permits the observation of biogeochemical interactions across scales from molecules and atoms to soil horizons.

Projects

SFB1076 AquaDiva de

FOR2179 MADSoil de

FOR918 Carbon flow on belowground food webs de

The role of modeling in hydrogeology

Visualisation of a modeled flow field inside the pores of an aquifer Visualisation of a modeled flow field inside the pores of an aquifer Image: Thomas Ritschel

The area of analytical and numerical, direct and inverse modeling and simulation plays a key role in the framework of an integrative research approach in hydrogeology. Apart from the fact that models are an important tool for the falsification of scientific theories, it is often only possible to comprehend the complex interdependencies and interactions of process effects in natural porous media by applying mathematical models. We develop and apply analytical and numerical models from the atomic scale over the aggregate- and pedon scale, up to the scale of small catchments. On the atomic scale, we are concerned with the modeling of the formation, growth and dissolution of pedogenic minerals and the interactions of pollutants at solid-liquid-, solid-gas-, and liquid-gas-interfaces. On the aggregate- and pedon scale, the focus lies on the simulation of coupled physical, chemical and biological processes as well as parameter identification using inverse numerical techniques. Furthermore, we concetrate on the computer-assisted development and optimization of experimetnal designs for the identification of biological, chemical and physical processes and parameters of reactive transport. On the field scale we are concerned with the simulation and parameter identification of flow - and transport processes in heterogeneous 3-dimensional pedo- and geosystems and the computer-assisted surveillance of pollutant- and matter transport up to the scale of small catchments.

Projects

SFB1076 AquaDiva de

FOR2179 MADSoil de

Reactive and carrier-facilitated transport in natural permeable porous media

Oil swimming on groundwater Oil swimming on groundwater Image: Robert Lehmann

The interaction of solutes and contaminants with reactive surfaces results in the phenomenon of retardation due to the retention of the sorbates at the biogeochemical interfaces in soil. The full understanding of the transport behavior of chemicals in natural porous media requires a characterization of the various interactions between the liquid, solid and gas phase. However, in case the solid sorbents are in colloidal size, they might be mobile themselves and cause carrier-facilitated transport of otherwise immbile, hydrophobic solutes and contaminants.

Projects

SPP1315 BGI in Soil de

SFB1076 AquaDiva de

FOR2179 MADSoil de

INFLUINS de