MSc Thesis: Romahn-2

Holocene community dynamics of Baltic zooplankton

Background:

Environmental DNA (eDNA) metabarcoding is a novel and but well-accepted method for assessing biodiversity via environmental samples like water or soil. In these samples, DNA can be stored for long periods of time depending on the environmental condition. The longest time period is in ice, frozen soil or sediments of seas and lakes for several thousand years. In the latter case, it is so called sedimentary ancient DNA (sedaDNA) which gives the opportunity to study biodiversity of the past. The DNA it contained can be extracted and sequenced for further community analyses.

Baltic Sea is a young, brackish sea with a dynamic history and is therefore a perfect study system to investigate the impact of changing environment on the food web. For this reason, PhytoArk (Leibniz SAW project) is interested to use living sediment archives and ancient DNA to understand responses of marine primary producers to environmental changes. Since zooplankton predates phytoplankton and are also an essential link in the food web of the Baltic Sea, we are interested in the community dynamics of Baltic zooplankton within this master thesis project.

Aim of thesis:

The main aim of this proposed thesis topic is to investigate the increasing anthropogenic impact on zooplankton in the Baltic Sea.

Methods:

The master thesis will be a mainly bioinformatic. Three sites in Baltic Sea reflecting several hundreds to thousand years will be analysed. Therefore, the chosen student will process DNA metabarcoding data with a bioinformatic pipeline, and reconstruct the community composition and complexity over time for the individual locations.
Furthermore, we will analyse the impact of temperature, salinity, nutrient availability and the richness of the main phytoplankton taxa (diatoms, dinoflagellates and cyanobacteria) on the zooplankton community and complexity to account biotic as well as abiotic factors. Depended on time issues, the predictability of this data can be tested using joint species distribution modelling.
The chosen student will gain expertise in metabarcoding, bioinformatics and paleoecology.

If interested, an introduction into the work within a clean room for seda DNA is possible.

Student requirements:

Knowledge about general genetics and barcoding, experience working with R, basic statistical knowledge, Linux experience preferable

Possible beginning:

Possible start date would be no earlier than February 2023

Contact:

Ph.D. candidate Juliane Romahn: juliane.romahn@senckenberg.de