Detailed Information on some Current Projects

SALIDRAA جوج: Salt in the system

Scientist: Jun.-Prof. Dr. Elisabeth Berger,  Prof. Dr. Ralf B. Schäfer

An increasing expansion of arid regions (desertification) due to climate change can be observed worldwide. At the same time, the need for water for a growing population and intensified agriculture is increasing.
The Draa valley in southern Morocco is the gateway to the Sahara and is severely affected by this problem. Climate change, overuse of water resources and sinking groundwater levels are contributing to the salinisation of soils and water bodies. This affects the survival of local plant and animal species, reduces agricultural production and endangers human well-being.
The German-Moroccan research project SalidraaJuj makes use of the concept of social-ecological systems to understand the problem of increasing river salinisation on the basis of the case study in the Draa Valley and to develop solution strategies for sustainable water use that contributes to the protection of nature and humans.

Project website:

This Project runs at the Social-Ecological Systems group.


Effects of land use on the coupling of terrestrial and aquatic food webs

emergenzfalle 2_klein.jpg Associated Phd student: Bonny Wenisch (née Krell) 

Streams and their adjacent riparian zones are closely linked by reciprocal flows of energy and biomass. Emergent aquatic insects represent one of the flows and are an important food source to riparian predators e.g. spiders. However, land use such as agriculture and pasture can result in habitat changes and consequently altered populations and communities. Therefore, land use could alter the flux of emergent insects to riparian predators. This project determines how land use affects the importance and magnitude of these interhabitat transfers using stable isotopes.

This project is funded by MBBWK Rheinland Pfalz/Wässerwiesen project

For further information see Wässerwiesen project page (in german)


Effects and prediction of pesticide mixtures

 Associated PhD student: Verena C. Schreiner


A wide variety of chemicals is used in agriculture resulting in the occurrence of substance mixtures in streams in agricultural landscapes. In this project, I analyse chemical monitoring data to identify the most frequently detected pesticides and pesticide mixtures and to identify variables (e.g. Catchment size, number of analysed compounds) that may be predictive of the frequency. In addition, I experimentally examine the effects of a field relevant fungicide mixture on leaf litter decomposition and analyse pesticide mixtures in agricultural areas using passive sampling with SDB disks and silicon rubber bands as well as edge-of-field sampling.


Incorporating spatial and seasonal variability chemical risk assessment (GETREAL)

Getreal Associated PhD student: Jonathan Jupke


Chemicals are widely used in every sector of European societies and are regulated in different political frameworks with the aim to protect from unacceptable effects. Current chemical risk assessment with respect to
chemical effects on non-target organisms largely follows a one-size-fits-all approach, focusing on sensitive single species tests or multi-species test systems. However, real world species assemblages vary in their composition over space and time and so may their sensitivity towards a chemical. Depending on the variability in sensitivity, the use of a single effect threshold can result in over- and underprotection. Hence, knowledge on this variability is pivotal for an efficient risk assessment. GETREAL will provide this information on the variability in chemical sensitivity and explore its consequences for risk assessment.

For more information see here:


Forecasting ion concentrations in surface waters considering global environmental change

catchments_derived_trial.png Associated PhD student: Le Trong Dieu Hien

Salinisation of surface waters is a global environmental issue that can regionally pose a risk to organisms in freshwater ecosystems, potentially leading to high environmental and economic costs. Global environmental change including climate and land use change can increase the transport of salts into surface water systems. Therefore, models are required to forecast dissolved ion concentrations in water bodies. Such models can help to determine the relevance of the different factors driving water ion concentrations and to identify streams and regions with the highest predicted changes. The aim of this project is to forecast the change in dissolved ion concentrations in running waters of Germany considering the potential influence of global environmental change on drivers of ion concentrations such as geology and precipitation patterns.


Statistical analysis of pesticide monitoring data

tiles_saxony.pngAssociated PhD student: Andreas Scharmüller

Within the framework of the NAP – National Action plan pesticides, I analyse the patterns of pesticide exposure in small stream catchments in Germany, as a basis for the establishment of a representative monitoring programme in agricultural landscapes. In detail, I examine how sampling sites should be spatially distributed to fulfil the criterion for a representative monitoring, which sampling period during the year can be regarded as representative, which substances should be considered in pesticide monitoring and how wastewater treatment plants affect the contaminant input into stream ecosystems. General information about the NAP can be found here.


Geostatistical analysis of chemical exposure and ecological quality of river networks

 Scientist: Dr. Mira Kattwinkel

Chemical and biological monitoring can only be conducted at certain monitoring sites. However, the related observations serve as proxies for the status of the whole river network. Geostatical analyses can help to complete the knowledge on the spatial and temporal distribution of both chemical stressors and ecological quality. On the one hand, they enable to use information on connected sites on the network that influence each other. On the other hand, they allow for a spatial interpolation between sampling sites. We are developing an open source tool for data preparation and for applying geostatistical modelling for German and French stream monitoring data, based on the work of Peterson & Ver Hoef (2010). This project is associated with the Upper Rhine Trinational Graduate Academy SERIOR.


Modelling the spatial distribution of aquatic invertebrates constrained by environmental stressors

lucas.jpeg Associated PhD student: Lucas Streib

Environmental conditions (e.g. habitat and water quality) are mainly responsible for the spatial distribution of aquatic invertebrates, which play a key role in several ecosystem processes. Habitat degradation and the input of agrochemicals (e.g. pesticides and nutrients) are the major stressors in aquatic streams. The project STRESSOR will try to examine the role of environmental constraints such as stressors and space in structuring the distribution of invertebrates varying in their traits through the development of a dynamic ecological model. It will be developed for several aquatic invertebrate species with different trait combinations related to dispersal and stressor tolerance. Furthermore predictions for the ecological effects of freshwater management measures related to habitat and water quality on the spatial distribution of aquatic invertebrates is aimed.

The STRESSOR project is part of the University Koblenz-Landau Graduate Academy B*M*U.


Macroscopic modeling and forecasting of aquatic invertebrates distribution based on mathematical networks

stressor_henriette.png Associated PhD student: Henriette Heer

Climate change effects have now been measured throughout all ecosystems and include, but are not limited to changes in species' distribution. To understand and mitigate these effects, reliable models of species dispersal are needed. As detailed dispersal models can become very expensive in computation time and memory usage, this subproject of the STRESSOR project aims at extracting a surrogate model of a given graph-based model in the context of distribution modelling of aquatic invertebrates. To achieve this, optimisation techniques are applied, that are ubiquitous in other disciplines but have not yet been used for dispersal simulation. The trade-off between exactness and speed-up of this surrogate will be evaluated and a thorough uncertainty and sensitivity analysis will be conducted.

The STRESSOR project is part of the University Koblenz-Landau Graduate Academy B*M*U.


Effects of fungicides on microbial communities and leaf decomposition

moritz_project Associated PhD student: MoritzLink

Fungicides account for approximately 45% of applied pesticides in the European Union.  They are a severe threat to freshwater fungi since the active ingredients are specifically designed to control terrestrial fungi during crop production. Based on  frequent applications and the persistence of many fungicides, freshwater ecosystems in agricultural catchments are subject to ecotoxicologically relevant exposure during the growing season. In a field study, I will analyse the responses of fungal communities and their dynamics as well as of ecosystem functioning in terms of allochthonous organic matter decomposition (a fundamental ecosystem function for stream ecosystems) to fungicides.


Influence of neonicotinoids on trophic relations and ecosystem processes

 Associated PhD student: Eva de Lima Fernandes

Neonicotinoids are a class of insecticides that, due to their physical and chemical properties, can be easily taken up and retained by terrestrial plants as well as transported to aquatic ecosystems via runoff from agricultural areas. These properties may be particularly important in forested headwater streams where decomposition of terrestrial plant parts, particularly leaves, is a key ecosystem process driven by microbial and invertebrate communities. In this project, I expose microbial and different types of invertebrate consumers to neonicotinoids through the water phase or through contaminated food source and examine the effects on their trophic relations and on the leaf litter decomposition process.

More detailed information on the project can be found here.