Category Archives: Multiple Stressoren

Molecular Ecology Module

On September 5th our new module “Molecular Ecology” will start. For one week we will generate molecular data to investigate patterns and factors influencing intraspecific genetic variation in benthic macroinvertebrates at the Forschungsinstituts Senckenberg in Gelnhausen. Subsequently, we will perform bioinformatic analyses in the second part of the module at University of Duisburg-Essen.

Study area will be the Rhein-Main-Observatorium.

Molecular Ecology Module

New project: metabarcoding and eDNA to assess impacts of multiple stressors on species communities in New Zealand rivers

We are starting a new project!

Together with our collaborators from the University of Otago, Florian and Jan will use metabarcoding and eDNA techniques to assess the impacts of multiple anthropogenic stressors on species communities in New Zealand rivers. Stay tuned for updates!

NZSamples2   NZSamples4 NZSamples3   NZSamples

New article in the Barcode Bulletin

We just published a short article in the Barcode Bulletin.

In the march issue (pages 10-12), Florian and Jan write about how different cryptic Deleatidium mayfly species from New Zealand show strongly different responses to anthropogenic stressors in the stream and the cosequences this has for ecosystem assessments.

PhD position DNA metabarcoding available

The University of Duisburg-Essen (Campus Essen)
Centre for Water and Environmental Research (ZWU)
Aquatic Ecosystem Research Group (Leese-Lab) offers

1 PhD position (Part-time 55%; salary equivalent TV-L 13)
in Genetic Monitoring / Metabarcoding
(BMBF German Barcode of Life 2 subproject)

The group of Prof. Florian Leese is interested in developing new
molecular approaches to assess the ecological status of aquatic
ecosystems. Specifically, we develop and apply DNA metabarcoding
to monitor changes in stream communities under environmental
stressors. Furthermore, we utilize genome- wide markers and perform
transcriptional profiling to understand population and organismal
responses to multiple stressors. As part of a recently granted subproject
within the large collaborative German Barcode of Life Project (GBOL2,
funded by the Federal Ministry of Education and Research, BMBF),
we want to bring DNA metabarcoding of freshwater invertebrates to
the application stage. In cooperation with our collaborators at
the Zoological Research Museum Alexander Koenig (Bonn, Germany),
the candidate will collect samples, perform experiments, generate and
analyse next-generation sequencing data on whole communities (amplicon
sequencing). Further reading: Elbrecht & Leese, PLoS ONE 2015, DOI:
10.1371/journal.pone.0130324; Macher, Salis et al., Ecological Indicators,

The successful candidate (f/m) will hold a Master in Biology, Chemistry or
Bioinformatics and has good experience in molecular lab work. Furthermore,
he/she has experience and strong interest in a programming or
scripting language (e.g. R, C, Python). Candidates will benefit from the
international and interdisciplinary research environment at the research
group, the GBOL2 project and the ZWU. Excellent high-throughput genomics
and bioinformatics equipment are available in the newly equipped labs.

The position will start as soon as possible initially for 2,5 years
(will be extended).  Deadline: 29. February 2016

For more information please visit:

Please send applications as a single pdf file with reference code
42-16 to For questions please contact

We are one of the youngest universities in Germany and think in terms
of possibilities, not limitations. In the heart of the Ruhrregion,
we develop ideas of the future at our 11 faculties. We are strong in
research and teaching, live diversity, support potential and are highly
committed to an educational equality that has earned this name.

The University Duisburg-Essen aims at promoting
the diversity of its members (see http://www.uni- Applications from disabled persons
or equivalents according to ง 2 Abs. 3 SGB IX are encouraged.

The University Duisburg-Essen has been awarded for its effort to promote
gender equality with the “Total-E- Quality-Award”. It aims at increasing
the share of women in the scientific personnel and therefore explicitly
encourages women to apply. Women will be preferentially considered when
equally qualified according to the state equality law.

Link to original job offer: URL:

Prof. Dr. Florian Leese
University of Duisburg-Essen
Faculty of Biology
Aquatic Ecosystem Research
Universitaetsstrasse 5
D-45141 Essen, Germany

+49 201.183-4053  |  @leeselab

New publication: Impact of multiple anthropogenic stressors on cryptic mayfly species of the genus Deleatidium


Together with Romana Salis, Katie Blakemore and Christoph Matthaei from the University of Otago (New Zealand) and Ralph Tollrian from the Ruhr University Bochum, Jan Macher and Florian Leese investigated the impact of multiple anthropogenic stressors on morphological cryptic species of the New Zealand mayfly genus Deleatidium.The genus Deleatidium is an important indicator taxon in New Zealand, commonly thought to indicate good water quality. In their newly published paper in the Journal Ecological Indicators with the title “Multiple-stressor effects on stream invertebrates: DNA barcoding reveals contrasting responses of cryptic mayfly species”, Jan and Florian could show that Deleatidium species show contrasting responses to agricultural stressors. While stressors have strong negative effects on some species, other species show no reaction to stressors at all. This has consequences for future water quality assessments as not all species are versatile indicators of poor water quality. The data show that more information on the ecology of freshwater taxa is urgently needed.