Erica B. Young Assistant Professor BSc University of Western Australia 1988 PhD Monash University 1999 Postdoctoral Research Fellow Queen's University of Belfast 1999-2002	Office: Lapham 593 Phone: 414-229-3257 FAX: 414-229-3926 Email: ebyoung@uwm.edu Personal Homepage
Plant and Algal Ecophysiology

Research Interests

Algal Ecophysiology : My research on algae is focused on photosynthesis, nutrient acquisition and nutrient limitation. This research has three foci : Phosphate acquisition by freshwater phytoplankton and benthic filamentous algae. This includes expression and function of alkaline phosphatase (AP), use of organic P sources, and the use of AP to assess P limitation. Inorganic carbon acquisition by algae and regulation by variable light, carbon dioxide and nutrient availability; the interactions between energy metabolism and inorganic C acquisition. Nitrogen uptake, storage and assimilation and regulation of nitrate reductase in marine brown algae in response to environmental stimuli. The ecological role of viral lysis of bacteria and phytoplankton in nutrient release and cycling in freshwater environments. Using chlorophyll a fluorescence to assess nutrient limitation in phytoplankton and toxins in aquatic systems : A range of methods have been applied to determine nutrient limitation in phytoplankton but parameters of nutrient stress that can be reliably applied to field phytoplankton populations are still elusive. My ongoing research is examining the use of a nutrient-induced chlorophyll a fluorescence-based assay as a rapid, cheap diagnostic tool of nutrient limitation in freshwater phytoplankton. Research is also focusing on using parameters of chlorophyll fluorescence in microalgae as a rapid ecotoxicological testing system for aquatic toxins. Pitcher Plant Nutrient Ecology : This research is examining nutrient metabolism in carnivorous pitcher plants in the Cedarburg Bog at the UWM Field Station. We have been examining the role of nitrogen nutrition in determining plant morphology of two distinct populations of the Northern Pitcher Plant Saracennia purpurea. My research interests in S. purpurea are also in the balance between nutrient acquisition via the roots and from the pitchers, as well as the microbial community and enzymes for digestion and nutrient assimilation present in the pitcher fluid. Long Term Ecological Change in a Wetland : This project is focused in understanding long term changes in vegetation composition of the Cedarburg Bog wetland using long-term datasets and vegetation surveys from 1991 and 2006. We are investigating the spread of the invasive species Rhamnus frangula (Glossy Buckthorn) in Cedarburg Bog to understand the factors driving the establishment of this invasive species in different wetland communities. This project also involves landscape classification using aerial photographs and characterizing the hydrological environment.

Selected Publications

Young, E.B., Dring, M.J. and Berges, J.A. 2007. Intertidal Fucus species show novel patterns of nitrate reductase activity, unaffected by irradiance and ammonium. Journal of Phycology. In Press. Young E.B., Dring M.J., Savidge G., Birkett D.A. and John A. Berges. 2007 Seasonal variations in nitrate reductase activity and internal N pools in intertidal brown algae are correlated with ambient nitrate concentrations. Plant Cell and Environment 30: 764-774. Young, E.B. and Beardall J. 2005. Modulation of photosynthesis and inorganic carbon acquisition in a marine microalga by nitrogen, iron and light availability. Canadian Journal of Botany 83 (7): 917-928. Young, E., van Elven, B., Lavery, P., Berges, J. & Dring, M. 2005. Inorganic nitrogen profiles in seagrass meadows and spatial patterns of nitrate reductase activity in macroalgal epiphytes. Marine Ecology Progress Series. 288: 103-114. Young, E, Bootsma, H and Berges J. 2004. Can Activity of Enzymes Involved in Nutrient Assimilation be Useful as Indices of Nutrient Status in Cladophora? 'Cladophora Research and Management in the Great Lakes' A Workshop at the Great Lakes WATER Institute, UWM, Dec 8, 2004. http://www.uwm.edu/Dept/GLWI/cladophora/page_report.html Bootsma, H, Young, E.B. and Berges, J.A. 2004. Temporal and spatial patterns of Cladophora biomass and nutrient stoichiometry in Lake Michigan. 'Cladophora Research and Management in the Great Lakes' A Workshop at the Great Lakes WATER Institute, UWM, December 8, 2004. http://www.uwm.edu/Dept/GLWI/cladophora/page_report.html Young, E. and Beardall, J. 2003. Photosynthetic function in Dunaliella tertiolecta during a nitrogen starvation and recovery cycle. Journal of Phycology 39: 897-905. Young, E. and Beardall, J. 2003. Transient perturbations in chlorophyll a fluorescence elicited by nitrogen re-supply to nitrogen-stressed microalgae: distinct responses to NO3- versus NH4+. Journal of Phycology 39: 332-342 Young, E., Giordano, M. and Beardall, J. 2001. Inorganic carbon acquisition by Dunaliella tertiolecta (Chlorophyta) involves external carbonic anhydrase and direct HCO3- utilisation (insensitive to the anion exchange inhibitor DIDS). European Journal of Phycology 36: 81-88. Beardall, J. Young, E. and Roberts, S. 2001. Interactions between nutrient uptake and cellular metabolism: approaches for determining algal nutrient status. Aquatic Sciences. 63 (1) 44-69. McMahon, K, Young, E, Montgomery, S, Cosgrove, J, Wilshaw, J and Walker, DI. 1998. Status of a shallow seagrass system, Geographe Bay, southwestern Australia. Journal of the Royal Society of W.A. 80: 255-262. Johansson, S. Wide, M., Young, E. and Lindblad, P. 1993. Expression of alkaline phosphatase in mature mouse placenta visualised by in situ hybridization and enzyme histochemistry. Anatomy and Embryology 187: 409-414. Atkins, C.A., Storer, P.J. and Young, E.B. 1991. Translocation of nitrogen and expression of nodule-specific uricase (nodulin-35) in Robinia pseudoacacia. Physiologia Plantarum 83: 483-491.