I carry out research on groundwater quality in rural areas. This work is mainly focused on nitrate loss to groundwater from agricultural land and on synthetic organic compounds including pesticides and veterinary pharmaceuticals. I also study interactions between groundwater and surface water, and phosphorus loss to surface waters by different hydrological pathways. I work on groundwater-dependent wetlands including turloughs (karstic temporary lakes), fens and coastal dune slacks. Much of this research ties in closely with implementation of the EU Water Framework Directive in Ireland. I have a particular interest in karst hydrogeology, including karst water quality and groundwater - surface water interactions in karst regions.
Recently completed research projects include:
- The impact of on-site wastewater effluent on karst springs (SFI iCRAG studentship) (Research partner and PhD co-supervisor)
- EcoMetrics - environmental supporting conditions for Groundwater Dependent Terrestrial Ecosystems (EPA Research Programme 2014-2020): Environmental supporting conditions for fens (Research partner and PhD co-supervisor)
- Emerging organic contaminants arising in rural environments: investigations in karst and fractured bedrock aquifers (SFI iCRAG studentship / Teagasc Walsh Fellowship) (Principal Investigator and PhD supervisor)
- Nitrogen attenuation along delivery pathways in agricultural catchments (Teagasc Walsh Fellowship) (Principal Investigator and PhD supervisor)
- Development of an ecohydrology framework for setting environmental flow standards for Irish rivers (EPA STRIVE Programme) (Research partner)
- The role of humid dune slacks in supporting plant and invertebrate diversity in sand dune ecosystems, and effects of human activities (TCD / National Parks and Wildlife Service / EPA) (Research partner and PhD co-supervisor)
- Combining earth observation and environmental tracing techniques for groundwater detection and evaluation in Ireland (CONNECT) (EPA STRIVE Programme) (Research partner)
- Evaluation and interpretation of groundwater monitoring data and the implications for groundwater in Ireland (EPA STRIVE Programme) (Fellowship supervisor)
- Assessment of the vulnerability of groundwater to pesticide inputs from Irish agriculture (pesticide mobility case studies) (Dept. Agriculture & Food Research Stimulus Fund Programme / Teagasc) (Research partner and PhD supervisor)
- Environmental supporting conditions for groundwater dependent terrestrial ecosystems (EPA STRIVE Programme) (Principal investigator)
Publications and Research output
A selection of recent publications is provided below.
Vucinic, L., O'Connell, D., Dubber, D., Coxon, C. & Gill, L. (2023) Multiple fluorescence approaches to identify rapid changes in microbial indicators at karst springs. Journal of Contaminant Hydrology 254, 104129. https://doi.org/10.1016/j.jconhyd.2022.104129
McAleer, E., Coxon, C., Mellander, P.-E., Grant, J. & Richards, K. (2022) Patterns and drivers of groundwater and stream nitrate concentrations in intensively managed agricultural catchments. Water, 14, 1388. https://doi.org/10.3390/w14091388
Vucinic, L., O’Connell, D., Teixeira, R., Coxon, C. & Gill, L. (2022) Flow cytometry and faecal indicator bacteria analyses for fingerprinting microbial pollution in karst aquifer systems. Water Resources Research, 58, e2021WR029840 https://doi.org/10.1029/2021WR029840
Bijkerk, E., Regan, S., Johnston, P., Coxon, C. & Gill, L. (2022) The challenge of developing ecohydrological metrics for vegetation communities in calcareous fen wetland systems. Frontiers in Earth Science, 10, 917233. https://doi.org/10.3389/feart.2022.91723
Gill, L., Bhatnagar, S., Bijkerk, E., Regan, S., Somlai, C., Naughton, O., Ghosh, B., Waldren, S., Coxon, C. & Johnston, P. (2022)EcoMetrics – Environmental supporting conditions for groundwater-dependent terrestrial ecosystems.EPA Research Report No. 403, Environmental Protection Agency, Wexford, 54pp.
Bhatnagar, S., Gill, L.W., Waldren, S., Sharkey, N., Naughton, O., Johnston, P., Coxon, C., Morrissey, P. & Ghosh, B. (2021)Ecohydrological metrics for vegetation communities in turloughs (ephemeral karstic wetlands).Ecohydrology, 14(6), e2316, https://doi.org/10.1002/eco.2316
Mooney, D., Richards, K.G., Danaher, M., Grant, J., Gill, L., Mellander, P.-E. & Coxon, C.E. (2021) An analysis of the spatio-temporal occurrence of anthelmintic veterinary drug residues in groundwater. Science of the Total Environment, 769, 144804, https://doi.org/10.1016/j.scitotenv.2020.144804
Mooney, D., Richards, K.G., Danaher, M., Grant, J., Gill, L., Mellander, P.-E. & Coxon, C.E. (2020) An investigation of anticoccidial veterinary drugs as emerging organic contaminants in groundwater. Science of the Total Environment, 746, 141116, https://doi.org/10.1016/j.scitotenv.2020.141116
Mooney, D., Coxon, C., Richards, K., Gill, L., Mellander, P-E. & Danaher, M. (2020) A new sensitive method for the simultaneous chromatographic separation and tandem mass spectrometry detection of anticoccidials, including highly polar compounds, in environmental waters. Journal of Chromatography A, 1618, 460857, https://doi.org/10.1016/j.chroma.2020.460857
Mooney, D., Coxon, C., Richards, K., Gill, L., Mellander, P-E. & Danaher, M. (2019) Development and optimisation of a multiresidue method for the determination of 40 anthelmintic compounds in environmental water samples by solid phase extraction (SPE) with LC-MS/MS detection. Molecules, 24, 1978, https://doi.org/10.3390/molecules24101978
Irvine, K., Coxon, C., Gill, L., Kimberley, S. & Waldren, S. (2018) Turloughs (Ireland). In Finlayson, C.M. Milton G., Prentice R. & Davidson N. (eds.), The Wetland Book, Springer, Dordrecht, 1069-1077.
McAleer, E.B., Coxon, C.E., Richards, K.G., Jahangir, M.M.R., Grant, J. & Mellander, P.E. (2017) Groundwater nitrate reduction versus dissolved gas production: A tale of two catchments. Science of the Total Environment, 586: 372-389.
McManus, S-L., Coxon, C.E., Mellander, P-E., Danaher, M. & Richards, K.G. (2017) Hydrogeological characteristics influencing the occurrence of pesticides and pesticide metabolites in groundwater across the Republic of Ireland. Science of the Total Environment, 601-602: 594-602.
Minet, E.P., Goodhue, R., Meier-Augenstein, W., Kalin, R.M., Fenton, O., Richards, K.G. & Coxon, C.E. (2017) Combining stable isotopes with contamination indicators: a method for improved investigation of nitrate sources and dynamics in aquifers with mixed nitrogen inputs. Water Research, 124: 85-96.
Tedd, K., Coxon, C., Misstear, B., Daly, D., Craig, M., Mannix, A. & Hunter Williams, T. (2017) Assessing and developing natural background levels for chemical parameters in Irish groundwater. EPA Research Report No. 183, Environmental Protection Agency, Wexford, 71pp. ISBN 978-1-84095-659-7.
Webster, K.E., Tedd, K., Coxon, C. & Donohue, I. (2017) Environmental Flow Assessment for Irish Rivers. EPA Research Report No. 203, Environmental Protection Agency, Wexford, 76pp. ISBN 978-1-84095-693-1.
For full publication list please click here.