Coastal dune systems comprise a complex network of habitats that support a range of important species, many of which are of nature conservation significance. This diversity of habitats and species reflect a range of environmental conditions, not least the access to water. The challenge for nature conservation lies not only in the management of human activities to reduce risks to habitat degradation and biodiversity loss, but also in understanding the role that climate change will have on the function and behaviour, and ultimately the resilience of communities and species assemblages to shifts in environmental forcing.
Topographic heterogeneity and the capacity of coastal sand in storing water lead to a spatially varying water table, and the presence of a range of wetlands, from dune slacks to dune depression ponds to saline intrusion marshes, all defined by distinct ecohydrologies. Climate change and anthropogenic interventions pose significant and multiple pressures on dune habitats, and as hydrology is particularly sensitive to these, impacts can be seen in changes in species distributions in both time and space.
This PhD focuses on the Sheskinmore – Magheramore protected (SPA, SAC) dune system in northwest Ireland, which is home to a diverse collection of dune slack and pond habitat amongst a complex dune topography. The site has been the focus of several studies to date, ultimately leading to the emerging focus of this project whilst at the same time providing a large, and growing, dataset. The aim of the PhD is to:
a) examine the variability in ecohydrology across the Sheskinmore – Magheramore dune system
b) evaluate the associations between species, communities and hydrological regime
c) develop a high resolution hydrological-hydraulic model of the system to enhance understanding of its hydrological behaviour and to further explore ecological-hydrological linkages
d) assess the vulnerabilities of sub-systems and communities to potential climate- or human- driven environmental forcing through a coupled hydrological-hydraulic modelling / water requirements approach.
The PhD will involve:
High resolution UAS technology and geophysical approaches, in addition to surface and sub-surface sampling to examine the full 3D and subsurface structure of the dune system, and the water table including its temporal variation.
Maintaining and extending the hydrological monitoring network at the site (for example continuous surface and ground-water level monitoring with loggers).
Detailed mapping of vegetation across the site and its combination with hydrological data and model simulation results in order to establish relationships between species/communities and the hydrological regime.
Modelling, using state-of-the-art coupled hydrological/hydraulic code, the dunescape ecohydrology and the use of the models to investigate the hydrological, and in consequence, ecological impacts of climate and management change on the system