Stream Ecology Group
Stream Ecology Group
The goal of the Stream Ecology Group is to understand the anthropogenic impacts on stream ecosystem functioning and biodiversity. We achieve this goal principally by field-based studies (in-situ experiments or surveys). In individual projects, we also reach out to other freshwater ecosystems. With our projects, we aim at contributing to conservation and management of these endangered ecosystems.

Group Members

Andreas Bruder (Group Leader)

Giorgia Frei (MSc Student)

Mojgan Zare (exchange PhD-Student of Isfahan University of Technology)

Pejman Fathi (exchange PhD-Student of Isfahan University of Technology)

Alireza Esmaeili (exchange PhD-Student of Isfahan University of Technology)

Liam O'Reilly (PostDoc)

Laura Thomas-Sleiman (BSc Student)


Past group members

Gabriele Consoli (MSc-Student 2015-2016): Gabriele's thesis on "Quantifying and predicting the effects of water abstraction on macroinvertebrate fauna and ecosystem function in alpine streams" elucidated the effects of hydropower dams on stream ecosystems based on fieldwork in two streams in the Val Blenio, Ticino. Gabriele moved on to do a PhD in Chris Robinsons group at eawag.

Julien Cornut (PostDoc 2015-2016): Julien was leading the initial projects on the diversity of aquatic hyphomycetes in various small and unimpacted streams in Ticino. He moved on to a PostDoc-position at MARE in Coimbra, Portugal.

Current Projects

Developing bioindicators for the Karun River, Iran, based on macroinvertebrate and fish communities. The Karun is the biggest river system in Iran, draining the Zagros mountain range in the south-west of the country. Its ecosystems are increasingly threatened by rural, agricultural and aquacultural development. With this project, in collaboration with the Isfahan University of Technology, we develop bioindicators based on 53 sites sampled in four seasons in 2018/2019 to support management of this unique river and its ecosystems. Funding bodies: Swiss Leading House for South Asia and Iran and Iranian Ministry of Science, Research and Technology. Group members involved: Pejman Fathi, Mojgan Zare, Alireza Esmaeili, Andreas Bruder. Project partners: Dr. Eisa Ebrahimi IUT. Duration: 2018-2021. The project has been endorsed by the swissuniversities Centre for Development and Cooperation.

Testing the consequences of degradation of riparian forest on detritus-based food webs in temperate and neotropical streams. Degradation of riparian vegetation is a common consequence of agricultural and forestry activities. Because detritus-based food webs in streams are intimately linked to organic matter inputs from the riparian vegetation, they are severely impacted by its degradation. In this project, in collaboration with the University of Vila Velha in Brazil, we aim to understand these impacts with a food-web perspective and explore the importance of changes in various biodiversity metrics. The project has a specific outreach component with stakeholder workshops in Brazil and Switzerland. Funding bodies: Swiss National Science Foundation and Brazilian National Council for Scientific and Technological Development. Group members involved: Andreas Bruder. Project Partners: Prof. Marcelo S. Moretti UVV, Prof. Florian Altermatt eawag/UZH. Duration: 2020-2023

Exploring the marvellous diversity of aquatic hyphomycetes. Aquatic hyphomycetes are the main microbial decomposers of organic matter entering stream food webs from the riparian vegetation. Despite their importance for ecosystem processes, which also depends on various aspects of biodiversity, knowledge on their biodiversity and biogeography is still incomplete. With projects in this topic, we aim at describing the biodiversity of aquatic hyphomycetes on from local to continental scales using established and novel molecular approaches coupled with traditional mycological techniques. Funding bodies: Fondazione Bolle di Magadino, Swiss Federal Office for the Environment. Group members involved: Julien Cornut, Andreas Bruder. Project Partners: Dr. Sophie De Respinis LMA. Duration: 2015-2020

Ecomorphology and ecosystem functioning of lake shores (Lake Lugano). Lake Lugano is a peri-alpine lake in southern Switzerland and northern Italy that is experiencing a range of anthropogenic impacts, including urban, industrial, and agricultural development. With projects in this topic, we aim at understanding the role of shoreline ecomorphology on the distribution of novel pollutants (i.e. microplastics) and on key ecosystem functions (i.e. organic matter processing) on the aquatic-terrestrial ecotones. Findings from these projects will feed into guidelines for shoreline management by CIPAIS and the regional administrations. Funding bodies: International Commission for the Protection of Italian-Swiss Waters (CIPAIS). Group members involved: Giorgia Frei, Laura Thomas-Sleiman, Andreas Bruder. Project Partners: Dr. Sandro Peduzzi DTI, Dr. Serge Stoll UNIGE. Duration: 2019-2020

Effects of variation in atmospheric electricity on microbial ecology at Lake Cadagno. The electric charge of the atmosphere varies with a daily rhythm. This has consequences on the activity of microbes and invertebrates living in ecosystems and interacting with the ions surrounding them. With measurements and experiments in various habitats of Lake Cadagno in Val Piora, we aim at elucidating these understudied links between the atmosphere and aquatic ecosystems and how these links are affected by human activities, e.g. the use of agrochemicals. Funding bodies: Swiss National Science Foundation. Group members involved: Liam O’Reilly, Andreas Bruder. Project Partners: Dr. Ellard Hunting (PI) Uni Bristol. Duration: 2020-2021


Past Projects

Hydropeaking effects on stream ecosystems

Hydropower production based on high-altitude reservoirs cause extreme discharge fluctuations in receiving rivers. This phenomenon, called hydropeaking, results in extremely fast changes of habitat conditions in river ecosystems with drastic consequences on its biota. Current environmental legislation addresses this issue but its implementation lacks experience and case studies. Based on metaanalyses of data and experiences from case studies of hydropeaking impact assessments and mitigation projects we provided expertise to the Swiss Federal Office for the Environment for the development of their guidelines. Group members involved: Gabriele Consoli, Andreas Bruder. Duration: 2017


Open Positions

We are looking for group members that have a passion for applied freshwater ecology. To fit the group, they should have a grounded and independent personality while being curious for the natural world and its phenomena. Students are welcome to approach Andreas Bruder to discuss possibilities to develop a BSc or MSc project in any of the research activities of the group. Specifically, we have the following open positions, which include flexibility for development/adaptation of research questions based on the student’s interests:

Master projects

Organic matter processing on Lake Lugano shorelines: The project aims at understanding the role of ecomorphology on the accumulation and microbial processing of organic matter (plant litter from the riparian vegetation) in the aquatic-terrestrial ecotone of Lake Lugano shorelines. Plant litter is utilized by specialized microbial decomposers and contributes substantially to carbon cycling in these ecosystems. In this project, we will study plant litter accumulation and processing in various sites on an ecomorphological gradient. Standardized substrate (i.e. cotton-strips) will be used to measure process rates as well as biomass and community composition of saprobic fungi. Timing: flexible, in 2020 or 2021. Duration: 6 to 12 months. Requirements: basic knowledge in aquatic ecology and environmental management.

The role of functional diversity for carbon cycling in streams: Ecosystems of forested streams host highly diverse microbial and invertebrate communities that perform crucial ecosystem functions, including processes contributing to carbon and nutrient cycling. These processes are often altered by anthropogenic impacts on water quality and the riparian vegetation. This project will quantify trophic links between main resources of organic matter (fine and coarse particulate organic matter) and specialized invertebrate groups, i.e. resource availability, resource uptake and invertebrate biomass. The project is coupled to a collaborative research program involving an international team of PhD-students and Postdocs. Timing: starting date December 2020 for 6 to 12 months. Requirements: basic knowledge in aquatic ecology and environmental management.


Guidelines and best practice of lake shoreline restoration: Lake shorelines are diverse and dynamic ecosystems, however, in central Europe and elsewhere they are often affected by urban development often resulting in loss of ecomorphological diversity and dynamic due to shoreline fortifications. An overview on guidelines and best-practice for restoration of lake shoreline ecomorphology is lacking but needed to support restoration projects. In this project, we will perform a meta-analysis of ecomorphological restoration projects of lake shores developed worldwide (accessible through the scientific literature and technical reports) to produce best-practice recommendations for federal and regional environmental offices. Timing: flexible, in 2020 or 2021. Duration: 4-6 months. Requirements: basic knowledge in aquatic ecology and environmental management.


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