QUADRAT DTP: Investigating the timing and causes of nitrogen cycle changes in Bronze Age Ireland

A fundamental alteration in the nitrogen cycle during the Bronze Age in Ireland has been identified through isotope analysis of wild and domesticated faunal remains and attributed to intensified land management during this time (Guiry et al. 2018). The timing of the shift broadly coincides with palynological evidence for widespread land clearance in the Middle Bronze Age (~1600 BCE) and Late Bronze Age (~1000 BCE) that supports an anthropogenic explanation for the environmental shift (Plunkett 2009) but a climate driver cannot be ruled out. This project will investigate the timing, extent and potential causes of the nitrogen fractionation shift through a palaeoenvironmental analysis of sedimentary sequences and an examination of dietary evidence spanning the Bronze Age.

Specific research questions include:
1) Is a nitrogen shift detectable in sedimentary sequences, including peatlands which were unlikely to have been directly impacted by intensified farming?
2) Does the archaeological record accurately reflect the extent of Bronze Age land-use, and can intensification be detected during the period of interest?
3) How do changes in land-use manifest in the subsistence record, determined from multi-proxy palaeodietary information from the archaeological record?
4) What was the relationship of land-use and/or nitrogen shifts, if any, to climate change during this period?

Methods
1) Palaeoenvironmental sequences will be collected from suitable lake and peatland sites in areas demonstrating contrasting densities of Bronze Age activity in Ireland (determined from Sites and Monuments Records in the two jurisdictions of the island). Tephrochronology and 14C dating will be used to isolate the Bronze Age levels of the sequences, which will then be investigated at centennial-scale resolution for land-use history (pollen analysis), palaeoclimate (pollen influx; testate amoebae – peatlands only) and δ15N analysis. Higher resolution analysis will be conducted across periods of major transitions to enable the timing of those events to be refined.
2) The relationship between land-use changes, subsistence and diet will be investigated using stable isotope analysis of archaeobotanical, archaeofaunal and human remains from a selection of Bronze Age archaeological sites in Ireland. Previously published data will be integrated into the study alongside newly generated data.

This multi-proxy approach will comprise the first integrated investigation of land-use changes, diet and environmental impacts in Irish prehistory and will enable a deeper understanding of the role of humans in driving systemic ecosystem change.

Research training: Applicants will be expected to have some background in palaeoecology and/ or stable isotope analysis. The project will include training in necessary skills including fieldwork, palaeoenvironmental techniques, stable isotope analysis (including sample preparation, data generation and analysis), age-modelling and data handling. Palaeoenvironmental studies will be undertaken at QUB. Stable isotope data will be generated in Aberdeen and QUB.

ELIGIBILITY

Candidates should have (or expect to achieve) a minimum of a 2.1 Honours degree in a relevant subject. Applicants with
a minimum of a 2.2 Honours degree may be considered providing they have a Distinction at Master’s level.

APPLICATION PROCEDURE:

• Apply for Degree of Doctor of Philosophy in the School of Natural and Built Environment (subject Archaeology and Palaeoecology)
• State name of the lead supervisor as ‘Name of Proposed Supervisor’ on application
• State ‘QUADRAT DTP’ as Intended Source of Funding
• Select the ‘Visit Website’ link below or visit https://dap.qub.ac.uk/portal/user/u_login.php to apply now

Please note that you do not need to submit a Research Proposal with your QUB postgraduate application, as the proposal is already contained within the advertisement.