Self-funded PhD opportunities
Biogenic sedimentary structures in deep time: proxies for ecosystem processes, ecosystem functioning, and as palaeoenvironmental indicators
- Application end date: All year round
- Funding Availability: Self-funded PhD students only
- Department: School of Earth and Environmental Sciences
- PhD Supervisor: Nicholas Minter and Gordon Watson
Organisms and their environments have been interacting and modifying one another since life began. Bioturbation, the biological reworking of sediments, is a critical ecosystem process that helps to regulate many significant ecosystem functions and benthic-pelagic coupling, including oxygenation of the sediment and nutrient cycling. Bioturbators are archetypal ecosystem engineers, modifying the environment in ways that affect other organisms, and this can result in long-term changes that have macroevolutionary consequences.
The purpose of the research is to study the activities of modern bioturbating organisms and investigate how biogenic sedimentary structures may be applied in the geological record as (i) proxies for ecosystem processes performed by palaeocommunities and levels of ecosystem functioning, and (ii) as palaeoenvironmental indicators.
The project will develop an experimental protocol to investigate the affects of interactions among different modes of bioturbation on ecosystem processes and functioning. The results will establish how identification of ecosystem processes in the form of biogenic sedimentary structures may be related to the level of ecosystem functioning by a community. This will then be applied to observations on trace fossil assemblages from the geological record. In particular it will be aimed at temporally and spatially large-scale biotic perturbations; understanding the loss of ecosystem processes and functioning prior to extinction events and the subsequent process of recovery, and identifying any keystone bioturbators whose loss precipitates ecosystem collapse or whose appearance facilitate recovery.
In addition, trace fossils are widely applied in palaeoenvironmental analysis. There are a number of models of idealized trace fossil assemblages that have been proposed to be indicative of different sedimentary environments. However, comparatively little research has been undertaken on modern analogue environments in order to analyse the governing factors on the distribution of biogenic sedimentary structures and to validate such models. This part of the project will involve conducting field-scale studies to establish the prevailing physicochemical conditions and gradients within a number of modern marine environments. Community-level data on the distribution of modern bioturbating organisms and their traces with respect to such physicochemical gradients will be used to compare with and validate existing models that are applied to the geological record. There will also be scope for carrying out original geological fieldwork in ancient equivalents.
This PhD opportunity is available to self-funded students. Bench fees may apply. For more information please contact the project supervisor.
How to apply:
To apply or make an enquiry, please visit postgraduate research: Earth and Environmental Sciences
All applications should use our standard application forms and follow the instructions given under the ‘Research Degrees’ heading on the following webpages: http://www.port.ac.uk/application-fees-and-funding/applying-postgraduate/#rd.
When applying please note the project code - SEES3220217