Applications are invited for a research studentship on the above topic.

Project objectives:
The leaching of nitrates in soils, combined with agricultural practice, is a potential threat to groundwater quality. This project proposes to quantify the movement and transformations of nitrate (NO3) from below the rooting zone to groundwater within agricultural systems. Denitrification is one of the main mechanisms for the reduction of NO3 movement through subsoils and groundwater, however this process may also lead to emissions of the greenhouse gas, nitrous oxide (N2O), rather than the environmentally benign di-nitrogen (N2). Internationally, subsurface denitrification has received only limited attention, due to methodological limitations that have more recently been overcome. Denitrification may prove to be the key process in determining NO3 occurrence in receiving waters. Understanding the microbial denitrification process within subsoil/groundwater will lead to a better understanding of the fate of NO3 delivery to groundwater and may also lead to management procedures for reducing both N2O emissions and NO3 leaching. The project will, for the first time in Ireland, quantify subsoil/groundwater denitrification rates and investigate the ratio of N2 and N2O, the end products of denitrification. The data generated will assist in the prediction of NO3 occurrence in receiving waters, environmental risk assessment and the achievement of Water Framework Directive objectives. Finally the N2/N2O emissions quantified can be used to refine Irish greenhouse gas emission inventories under the Kyoto Protocol.


Requirements:
Applicants should have a good primary degree (II1 or I) or an M.Sc. in an appropriate discipline (Environmental hydrogeology/Hydrology, Engineering, Environmental Science, Earth Science, Agricultural Science, etc.). Knowledge and experience of hydrology, soil physics and solute transport would be an advantage. A full driving license is required.

Funding:
The position is funded by the Department of Agricultures Stimulus Fund. The successful student will receive funding of €21,000 covering postgraduate stipend and tuition fees (Note: tuition fees for EU residents are currently c. €4,500 per annum).

Location and supervision:
The project student will be primarily based at the Teagasc Johnstown Castle Research Centre, Co. Wexford. It is possible that the student may spend periods of time in other research institutes. The student will be registered as a full time research student in the Department of Civil, Structural & Environmental Engineering, Trinity College Dublin, working under the supervision of Mr. Paul Johnston in association with Teagasc supervisors (Dr. Karl Richards and Dr M. Ibrahim Khalil).

Starting date:
The project will start as soon as a suitable candidate is recruited. The funding is for a three year Ph.D. project.

Application procedure:
Applicants should e-mail a curriculum vitae, detailing their qualifications/experience and a covering letter explaining why they wish to pursue this project. This should be sent to:

Paul Johnston,
Dept Civil, Structural and Environmental Engineering,
Trinity College, Dublin 2, Ireland
e-mail: pjhnston@tcd.ie,
Phone +353 1 896 1372

Closing date for applications: Until filled.