Dr Alwyn Rees

BSc (Liverpool), PhD (Wales)

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Senior Lecturer

Research | Current

Seaweeds exhibit an extraordinary range of size, morphology, structural complexity, productivity and life histories. In addition, they are important primary producers in coastal and estuarine ecosystems. For example, annual production of dry matter per unit area by intertidal seaweeds on exposed shores can exceed that of tropical rain forests or grasslands. However, this productivity can only be sustained through the acquisition and utilization of nutrients, particularly nitrogen and phosphorus. My main concerns are to understand the relationship between size, morphology and metabolism together with the ecophysiological mechanisms involved in seaweed growth, in particular the role of nutrients.

Specific areas of interest include the following:

  • Relationship between mass, surface area, volume, biochemical composition and metabolism in New Zealand seaweeds: Seaweeds have a range of size and morphologies from small filamentous to large laminate species. How does size and morphology influence the composition and metabolism of seaweeds?
  • Ammonium assimilation, phosphate uptake and growth rate in seaweeds: Assimilation of ammonium and uptake of phosphate are inhibited by methionine sulphoximine and furosemide, respectively. What is the effect of inhibitor titration (i.e. the increasing partial inhibition of ammonium assimilation and phosphate uptake) on growth rate in seaweeds?
  • The role of hyaline hairs in nutrient acquisition by seaweeds: Many seaweeds produce hyaline hairs and there is good evidence that they are involved in nutrient uptake. However, the mechanism(s) by which nutrients are transported from the hair (which can be up to 4 mm in length) to the thallus requires investigation. In addition, can hyaline hair characteristics be used to determine the nutrient status of seaweeds?
  • The physiology of reproduction in brown seaweeds: Of particular interest is the identity of the nutrient that limits gamete production and what controls the proportion of limiting nutrient released as gametes. Moreover, our understanding of reproduction in New Zealand brown seaweeds is very limited and, consequently, there are numerous opportunities to enhance our knowledge of the general biology of reproduction in this ecologically important group of algae.

 

Selected publications and creative works (Research Outputs)

As of 29 October 2020 there will be no automatic updating of 'selected publications and creative works' from Research Outputs. Please continue to keep your Research Outputs profile up to date.
  • Blain, C. O., Rees, T. A., Hansen, S. C., & Shears, N. T. (2019). Morphology and photosynthetic response of the kelp Ecklonia radiata across a turbidity gradient. LIMNOLOGY AND OCEANOGRAPHY, 65 (3), 529-544. 10.1002/lno.11321
    Other University of Auckland co-authors: Nick Shears
  • Li, M., Lundquist, C. J., Pilditch, C. A., Rees, T. A., & Ellis, J. (2019). Implications of nutrient enrichment for the conservation and management of seagrass Zostera muelleri meadows. AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS, 29 (9), 1484-1502. 10.1002/aqc.3141
    Other University of Auckland co-authors: Carolyn Lundquist
  • Rodgers, K. L., Rees, T. A. V., & Shears, N. T. (2015). A novel system for measuring in situ rates of photosynthesis and respiration of kelp. Marine Ecology Progress Series, 528, 101-115. 10.3354/meps11273
    Other University of Auckland co-authors: Nick Shears
  • Douglas, E. J., Haggitt, T. R., & Rees, T. A. V. (2015). Relationship between tissue phosphorus and seawater phosphate in the brown alga Hormosira banksii. New Zealand Journal of Marine and Freshwater Research, 49 (1), 64-68. 10.1080/00288330.2014.935737
  • Douglas, E. J., Haggitt, T. R., & Rees, T. A. V. (2015). Relationship between tissue phosphorus and seawater phosphate in the brown alga Hormosira banksii. New Zealand Journal of Marine and Freshwater Research, 49 (1), 64-68. 10.1080/00288330.2014.935737
  • Gévaert F, & Rees, T. A. V. (2015). Total chlorophyll and nitrogen storage in the green alga Ulva pseudolinza. Cahiers de Biologie Marine, 56, 313-318.
  • Douglas, E. J., Haggitt, T. R., & Rees, T. A. V. (2014). Supply- and demand-driven phosphate uptake and tissue phosphorus in temperate seaweeds. Aquatic Biology, 23 (1), 49-60. 10.3354/ab00601
  • Rees, T. A. V. (2014). Scaling and transport kinetics in aquatic primary producers. Marine Ecology Progress Series, 509, 103-112. 10.3354/meps10883

Contact details

Primary office location

LEIGH MARINE RESEARCH LABORATORY - Bldg 604
Level G, Room G01
160 GOAT ISLAND RD
LEIGH
AUCKLAND 0985
New Zealand

Secondary office location

LEIGH MARINE RESEARCH LABORATORY - Bldg 604
Level G, Room G01
160 GOAT ISLAND RD
LEIGH
New Zealand