A5040503553- Groundwater flow and contamination studies
- Groundwater and Isotope Geochemistry
- Hydrology and Watershed Management Studies
- Geochemistry and Geologic Mapping
- Hydraulic Fracturing and Reservoir Analysis
- Microbial Community Ecology and Physiology
- Drilling and Well Engineering
- Isotope Analysis in Ecology
- Water Quality and Resources Studies
- Wastewater Treatment and Nitrogen Removal
- Soil and Water Nutrient Dynamics
- Water Quality and Pollution Assessment
- Molten salt chemistry and electrochemical processes
- Tracheal and airway disorders
- Hydrocarbon exploration and reservoir analysis
- Analytical chemistry methods development
- Neutrino Physics Research
- Water Treatment and Disinfection
- Chromium effects and bioremediation
- Image Processing and 3D Reconstruction
- Advanced Chemical Sensor Technologies
- Atomic and Subatomic Physics Research
- Geophysical and Geoelectrical Methods
- Mass Spectrometry Techniques and Applications
- Radiation Detection and Scintillator Technologies
Ministry for the Environment
2024
GNS Science
1992-2023
Hutt Hospital
1991
Anaerobic ammonium oxidation (anammox) is important for converting bioavailable nitrogen into dinitrogen gas, particularly in carbon-poor environments. However, the diversity and prevalence of anammox bacteria terrestrial subsurface-a typically oligotrophic environment-are little understood. To determine distribution activity across a range aquifer lithologies physicochemistries, we analyzed 16S rRNA genes quantified hydrazine synthase transcripts sampled from 59 groundwater wells...
Abstract Groundwater dating using anthropogenic and natural tracer substances is a powerful tool for understanding groundwater dynamics improved management of resources. Due to limitations in individual methods, often multiple tracers are used reduce ambiguities. It commonly accepted that there need further complementary age tracers, addition current ones (e.g., tritium, SF 6 , CFCs). We propose potential new tracer, Halon‐1301 (CF 3 Br), which can easily be determined gas chromatography...
Abstract. Groundwater dating is an important tool to assess groundwater resources in regards their dynamics, i.e. direction and timescale of flow recharge, contamination risks manage remediation. To infer age information, a combination different environmental tracers, such as tritium SF6, are commonly used. However, ambiguous interpretations often faced, due limited set available tracers individual restricted application ranges. For more robust multiple need be applied complementarily (or...
Abstract. We recently discovered a new groundwater age tracer, Halon-1301, which can be used to date recharged after the 1970s. In previous study, we showed that Halon-1301 reliably inferred at majority of sites studied. At those sites, ages from agreed with SF6 and tritium, two reliable widely applied tracers. A few samples, however, reduced concentrations preventing meaningful interpretation its concentration. These were likely result degradation or retardation in aquifer. However, could...
Groundwater denitrification studies require the careful quantification of excess N2 to determine that nitrate reduction has taken place. The measurement corresponding noble gases Ne and Ar quantifies air in situ degassing. We compare, for first time, results from a high-precision quadrupole mass spectrometer (QMS) with low-cost PlasmaDetek (plasma emission detector) GC add-on capable analyzing all three (N2, Ne, Ar) single sample obtain reliable data calculations. Both methods can be used...
Abstract. We recently discovered a new groundwater age tracer, Halon-1301, which can be used to date recharged after the 1970s. In previous study, we showed that Halon-1301 reliably inferred at majority of studied sites. At those sites, ages from agreed with SF6 and tritium, two reliable widely applied tracers. A few samples, however, reduced concentrations preventing meaningful interpretation its concentration. These were likely result degradation or retardation in aquifer. However,...
Abstract. Groundwater dating is an important tool to assess groundwater resources in regards their dynamics, i.e. direction and time scale of flow recharge, contamination risks manage remediation. To infer age information, a combination different environmental tracers, such as tritium SF6, are commonly used. However, ambiguous interpretations often faced, due limited set available tracers individual restricted application ranges. For more robust multiple need be applied complementarily it...
<p><span lang="EN-US">Combined <sup>14</sup>C and <sup>3</sup>H measurements on groundwater from Christchurch, New Zealand, are proving vitally important for revealing water age distributions, which key to understanding the diverse flows in system (including younger potentially polluting near surface much older pristine depth). The deep gravel aquifers 350-500m thick under Christchurch have...
Abstract Background Anaerobic ammonium oxidation (anammox) is important for converting bioavailable nitrogen into dinitrogen gas, particularly in carbon poor environments. Yet, the diversity and prevalence of anammox bacteria terrestrial subsurface – a typically oligotrophic environment little understood across different geochemical conditions. To determine distribution activity range aquifer lithologies physicochemistries, we analysed 16S rRNA genes, metagenomes metatranscriptomes,...