Research Interests and Opportunities
Great Lakes Nutrient Cycling and Algal Ecology
-organic P use, algal blooms, viral lysis…
Projects are focused on understanding use of organic P sources by algae in nearshore and offshore Lake Michigan. We have been examining alkaline phosphatase (AP) activity using bulk assays and localization using enzyme-linked fluorescence (ELF-97) assays. We are interested in how P sources, including organic P, which are excreted from invasive Dreissenid mussels can support primary production in nearshore Lake Michigan, possibly fueling blooms of the nuisance filamentous alga Cladophora and harmful cyanobacteria.
Chelsea Lowes is studying how different algae and cyanobacteria can use a range of organic P sources. We are also investigating viruses present in Lake Michigan and small urban ponds inMilwaukee. Alicia Hanson is examining the role of viral lysis in nutrient release and supply to phytoplankton. Virus research is in collaboration with John Berges and Steve Wilhelm (Univ Tennessee).
Erica Young is an affiliated scientist at the Great Lakes WATER Institute (GLWI). Field-work in Lake Michigan is carried out on the R/V Osprey or R/V Neeskay out of the GLWI. We have been involved in an investigation of a late-winter phenomenon of ‘The Doughnut’ in central southern Lake Michigan with Chas Kerfoot and Sarah Green at Michigan Tech University. See Gallery for photos of our 2007 cruise on the R/V Laurentian.
Wetland Plant Ecology
– vegetation change, invasive species, carnivorous pitcher plants…
Research focused on wetland ecology and processes is based at the Cedarburg Bog out of the UW-Milwaukee Field Station in collaboration with Jason Mills and Field Station staff Jim Reinartz and Gretchen Meyer. We are examining long term change in vegetation composition, possibly in response to climate and land-use changes. We are using long term records of research and aerial photography back to the 1940’s as well as update vegetation surveys. We are also examining the progression of the invasive species glossy buckthorn (Rhamnus frangula) in the Cedarburg Bog using annual growth rings to estimate age and growth rate of the plants in different parts of the Bog. This research is partially funded by UWM Research Growth Initiative. In 2008, Jason Berg is starting a new project to examine invasive glossy buckthorn by measuring the role of seed deposition (propagule pressure) in establishment of new seedlings.
Research on the nutrient ecology of the carnivorous northern pitcher plant Sarracenia purpurea is also focused in the Cedarburg Bog and nearby Sapa Bog. This research is collaboration with Gretchen Meyer and has been carried out by grad student Terry Bott. We have been examining how the distinct morphology of two populations of S. purpurea is influenced by nutrient and light availability and conditions within an acid bog and a neutral pH fen. We have been investigating the inside and outside leaf surfaces of S. purpurea using scanning electron microscopy (see pics in the Gallery) and examining the diversity and enzymes produced by the microbial community in S. purpurea pitchers.
- Mills JE, Schroeder J, Reinartz J, Meyer G, Young EB. Land cover and land use changes (1941 to 2000) on the landscape surrounding a large, undisturbed wetland. Submitted.
Mills JE, Reinartz J, Meyer GA and Young EB. An exotic invasive shrub has greater recruitment and broader distribution than native shrub species across diverse wetland habitats. Submitted
Mills J.E., Reinartz J.A., Meyer G.A., Young E.B. 2009. Exotic shrub invasion in an undisturbed wetland has little community-level effect over a 15-year period. Biological Invasions 11: 1803-1820.
Bott T, Meyer GA and Young EB. 2008. Nutrient limitation and morphological plasticity of the carnivorous pitcher plant Sarracenia purpurea in contrasting wetland environments. New Phytologist. 180: 631-641.
Algal Photosynthesis and Stress
– chlorophyll a fluorescence, carbon acquisition, nutrient limitation…
Erica Young maintains an active interest in algal photosynthesis – especially inorganic C acquisition and the effects of nutrient limitation on photosynthesis. Other interests are in constraints to phytoplankton productivity in natural systems and the potential effects of climate change (elevated CO2 and temperature) on phytoplankton production. Current projects include examining the effect of freezing stress on Cladophora photosynthetic viability using chlorophyll a fluorescence, and the use of chl a fluorescence indicators to examine toxic stress in algae. The research on detection of toxins using algal photosynthesis is being carried out by Chang Jae Choi using a Xe-PAM (Walz) and has been funded by the Center for Water Security (from Homeland Security) and was presented at the 2007 Society of Environmental Toxicology and Chemistry (SETAC) meeting .
Opportunities for undergrad or grad student projects are focused on elevated CO2 effects on algal photosynthesis and energy metabolism, interactions between algal photosynthesis and the acquisition of other nutrients.
Intertidal macroalgal nutrient ecology
– inorganic nitrogen uptake, assimilation and partitioning…
The initial part of this research was carried out in the beautiful Strangford Lough, from the Portaferry Marine Lab, Northern Ireland, in collaboration with Matt Dring and John Berges, funded by NERC UK. Lake Michigan is sadly devoid of the large intertidal brown algae Laminaria and Fucus species (although we did find the phaeophyte Pleurocladia lacustris epiphytic on Cladophora). The plan is to continue examining nitrate uptake and assimilation in intertidal brown macroalgae on the North American Atlantic coast and with Pacific species, but with all the fun stuff going on in the lakes, it may take some time to get there!
Nutrient uptake processes and enzymic indicies of assimilation can also be studied in the somewhat less charismatic filamentous algae found in freshwater ecosystems (e.g. see other research interests on Cladophora).
I am currently accepting new graduate students interested in research in these or related areas within the Dept Biological Sciences Graduate Program. Please contact me to discuss ideas, funding options and the application process.
There are always opportunities for undergraduate research projects in all the areas listed above. This can be done as independent study courses through Biological Sciences or Conservation and Environmental Sciences programs, or through UROP or McNair scholars programs – contact me for more details!