Verena Riedl
PhD Student

Profile

Biography

Verena is a PhD student interested in exploring the ecological impacts of environmental stressors on different levels of biological organisation ranging from the individual level to communities. For her PhD project, she focuses on the role species interactions play when it comes to how and to what extent contaminants at environmentally relevant concentrations can affect the population dynamics of an aquatic community. She works at Fera Science Ltd., where her practical work is based, and the University of York.  Prior to commencing her PhD project, Verena specialized in marine Biology and worked on determining the effects of climate change, in particular temperature, on life history traits of the common cuttlefish.  

Career

Research

Overview

Description of PhD

Title:  Direct and indirect effects in an aquatic Nanocosm under pesticide stress

Supervisor:  Dr. Roman Ashauer (University of York), Dr. Rachel Benstead (Fera Science Ltd.)

Funding: University of York; Fera Science Ltd., York.

Description of thesis:

When organisms are exposed to toxicants they can be influenced directly (e.g. growth or reproduction) and indirectly when interactions with other system components are altered. These ecological effects can be studied in micro- and mesocosms (MCs) but they are expensive, time consuming and few replicates are used. Higher ecological complexity leads to higher variability between replicates and the extrapolation of effect/response relationships is more difficult. As part of the regulatory risk assessment where effects of pesticides on non-target organisms are evaluated, MCs are only employed when the direct effect results of inexpensive and quick single-species tests raise concern. To date, very few small test systems exist to describe direct and indirect toxicant impacts on multi-trophic systems and they are rarely tested for reproducibility. The project focuses on the development and the characterization of a small, multi-trophic aquatic test system to bridge simple single-species tests and complex multi-factor MCs. This allows the assessment of toxicant impacts on basic community processes and system dynamics. The proximate goal is to challenge the system with contaminants to assess sublethal toxic effects on population dynamics and trajectories. The final goal is to compare the empirical results to the predictions made by an individual based model to evaluate whether single-species effect data are sufficient to predict community dynamics, or if it is necessary to assess the impacts on the system as a whole (including interactions) and to include these into effect models.

Publications

Selected publications

Matozzo V, Conenna I, Riedl V, Marin MG, Marčeta T, Mazzoldi C, A first survey on the biochemical composition of egg yolk and lysozyme-like activity of egg envelopment in the cuttlefish Sepia officinalis from the Northern Adriatic Sea (Italy), Fish and Shellfish Immunology (2015), doi: 10.1016/j.fsi.2015.04.026.