University of Otago, New Zealand

Chemistry

Te Tari Hua-Ruanuku

Professor Russell D. Frew

contact photo
Professor Russell D. Frew
Chemical oceanography
Tel: (03) 479 7913
Location: Science II, 3n12
rfrew@chemistry.otago.ac.nz


Main research interests

Current research projects

Determining the geographical origin of food and other commodities of interest: 
The geochemical composition of a natural product provides a inherent signature that can be related to its point of origin.  We are currently working on developing robust tools encompassing analyses (light isotopes, trace metals and heavy isotopes), databasing and statistical interpretation.  Projects on whole foods (e.g. honey, coffee, edible oils) are on-going and attention is now on deciphering the signal within complex mixtures.

Nitrogen in the oceans, fate and fluxes:
Nitrogen compounds i the ocean play an important role in sustaining primary productivity and some are implicated as potential climate modifiers.  However the the controls of the rates and pathways of the cycling of nitrogen from the relatively inert N2(g) through the essential nutrients NO3 and NH4, amino acids and various gaseous oxides is not well understood.  The potential of climate change underlines the importance of understanding the marine biogeochemistry of nitrogen.  For example, the regions of nitrogen fixation will increase with global warming thereby enhancing the marine fixed nitrogen pool.  On the other hand nitrous oxide is a significant greenhouse gas with a global warming potential 300 times that of CO2 on a molecular basis.  This project applies isotopic tools to unravel the complexities of the marine nitrogen systematics.

Selected references

  1. David, Gabrielle E., Russell D. Frew, Alan R. Hayman. Isotope fractionation during precipitation of methamphetamine HCl and discrimination of seized forensic samples.  Forensic Science International, 200, 123-139, 2010
  2. Van Hale, Robert and Russell D. Frew. Rayleigh distillation equations applied to isotopic evolution of organic nitrogen across a continental shelf. Marine and Freshwater Research, 61, 369–378, 2010
  3. David, Gabrielle E., D. Brynn Hibbert, Russell D. Frew and Alan R. Hayman. Significant determinants of isotope composition during HI/Pred synthesis of methamphetamine. Australian Journal of Chemistry, 63, 22-39, 2010
  4. Dempsey, D.E., P. J. Langhorne, N. J. Robinson, M. J. M. Williams, T. G. Haskell and R. D. Frew. Observation and modelling of platelet ice fabric in McMurdo Sound, Antarctica, Journal of Geophysical Research, doi:10.1029/2008JC005264, 2010
  5. Magar, S., S. Fitsimmons, R. Frew, D. Samyn and R. Lorrain. Composition and origin of amber ice and its influence on the behaviour of cold glaciers in the McMurdo Dry Valleys, Antarctica. Journal of Glaciology, 55(190), 363-372, 2009
  6. Benbow T.J., R.D. Frew and A.R. Hayman. Validation of a rapid and simple method for the preparation of aqueous organic compounds prior to compound specific isotope analysis. Organic Geochemistry, 39, 1(12), 1690-1702, 2008
  7. Croot P.L., K. Bluhm, C. Schlosser, P. Streu, E. Breithbarth, R. Frew and M. Van Ardelan. Regeneration of Fe(II) during EIFeX and SOFeX. Geophysical Research Letters, 35, L19606, doi:10.1029/2008GL035063, 2008
  8. Stephen R. Wing, Rebecca J. McLeod, Kim L. Clark, Russell D. Frew. Plasticity in diet of two echinoderm species across an ecotone: microbial recycling of forest litter and bottom-up forcing of population structure, Marine Ecology Progress Series, 360, 115-123, 2008
  9. Croot, P.L., R.D. Frew, S. Sander, K.A. Hunter, M.J. Ellwood, E.R. Abraham, C.S. Law and P.W. Boyd.  The effects of physical forcing on iron chemistry and speciation during the FeCycle experiment in the South West Pacific. Journal of Geophysical Research - Oceans, 112 (C6): Art. No. C06015, 2007.
  10. Hepburn, Christopher,  Jame Holborow, Stephen Wing, Russell Frew and Catriona Hurd.  Exposure to waves inhances the growth rate and nitrogen status of the giant kelp, Macrocytus pyrifera. Marine Ecology Progress Series, 339: 99-108 2007.
  11. Cornelisen, Christopher  D., Stephen.R. Wing, Kim L. Clark, M. Hamish Bowman, Russell D. Frew, Catriona L. Hurd. Patterns of macroalgal stable carbon and nitrogen isotope signatures: interaction between physical gradients and nutrient source pools. Limnology and Oceanography, 52, 820-832, 2007.
  12. Simon, Kevin S., Dev K. Niyogi, Russell D. Frew, and Colin R. Townsend. Nitrogen dynamics in grassland streams along a gradient of agricultural development. Limnology and Oceanography, 52: 1246-1257, 2007.
  13. Hepburn, Chris, Catriona Hurd, Russell Frew, Colony structure and seasonal differences in light and nitrogen modify the impact of sessile epifauna on the giant kelp Macrocystis pyrifera (L.) C Agardh.   Hydrobiologia, 560, 373-384, doi:10.1007/s10750-005-1573-7, 2006.
  14. Tian, F., Frew, R.D., Sander, S.G., Ellwood M.A. and Hunter, K.A.  Fe(III) speciation in surface transects and depth profiles across a frontal zone: the Chatham Rise, New Zealand, Marine and Freshwater Chemistry, 57 (5): 533-544 2006.
  15. Leonard, G. H., C. R. Purdie, P. J. Langhorne, T. G. Haskell, M. J. M. Williams, and R. D. Frew. Observations of platelet ice growth and oceanographic conditions during the winter of 2003 in McMurdo Sound, Antarctica, Journal of Geophysical Research, 111, C04012, doi:10.1029/2005JC002952, 2006
  16. Frew R.D., D.A. Hutchins, S. Nodder, S. Sanudo-Wilhelmy, A. Tovar-Sanchez, P.W.Boyd.  Particulate iron dynamics during FeCycle in subantarctic waters SE of New Zealand. Global Biogeochemical Cycles, 20, GB4S22, doi:10.1029/2005GB002558, 2006