Towards a paradigm shift in ecological risk assessment: developing novel ecosystem-basedapproaches to enhance biodiversity conservation

The current global and national declines in biodiversity mean there is an urgent need to develop more robust approaches for conserving key ecosystem functions and services. Ecological risk assessment is used to determine the likelihood of adverse ecological effects resulting from human impacts on the environment. In freshwater ecosystems, single indicators are commonly used.
These are often individual species which are used as proxies for the response of the ecosystem as a whole. However, this approach can give misleading results because single indicators, especially those based on laboratory assessments, may not necessarily be good indicators of overall ecosystem functioning and may lack realism. Moreover, different indicators may respond to environmental stress in different ways, and so the effects of loss of biodiversity on ecosystem function can be difficult to predict. More inclusive approaches, which account for what is happening throughout the ecosystem, could play a key role in providing ‘early warnings’ of sudden ecosystem changes due to environmental and anthropogenic pressures. This PhD project will use existing datasets to build a better understanding of the relationships between biodiversity and ecosystem functions in aquatic ecosystems. This evidence will be used to inform the development of new types of ecological risk assessments that incorporate more robust indicators of ecosystem health, and so findings from the project could make an important contribution to biodiversity conservation in different parts of the world.
The project will have three main aims:
- To examine the relationships between indicators of biodiversity and ecosystem functions in freshwater systems within the same eco- regions, and how the choice of indicator can affect measures of changes in overall freshwater ecosystem health.
- To evaluate the impact of chemical and other stressors on ecosystem functions, including any evidence for threshold effects, whether specific traits of species make them particularly vulnerable to loss and the potential impacts on ecosystem function.
- To determine the robustness of different indicators of ecosystem function in ecological risk assessments, and hence which indicators would be reliable measures of the response of the ecosystem as a whole, providing ‘early warnings’ of ecosystem damage in different eco-regions.

The student will be a member of the NERC Doctoral Training Partnership in “Adapting to the Challenges of a Changing Environment” (ACCE), which is a partnership between the Universities of Sheffield, Liverpool and York, the NERC’s Centre for Ecology and Hydrology (CEH) and the Natural History Museum (NHM).

The University of York will be the lead institution for the PhD and will serve as the primary base for the PhD student. The University of Sheffield will act as the second institution for the PhD student. The student will have desk space available in Professor Maltby’s group at the University of Sheffield, and will be encouraged to visit Sheffield and make use of the opportunities provided by co-supervision across two academic institutions. The student will also have the opportunity of spending at least 3 months with experts covering broad aspects of ecological risk assessment at Unilever, the CASE partner organisation, over the four years of the studentship.

The student will follow the requirements of the NERC ACCE PhD programme, and benefit from training activities provided at ACCE programme level by the Universities of York, Sheffield and Liverpool. The student will be registered in the Department of Environment and Geography at the University of York and follow the Department of Environment and Geography’s progression requirements. These are consistent with the requirements of the University of York, as set our by the York Graduate Research School.