Most recently I have been studying particular Kansas reservoirs in an attempt to better understand water quality issues related to land use in watersheds and the aging process where reservoirs fill with sediments at varying rates. With several students and faculty from my department, Civil and Environmental Engineering, and Chemistry, I am also studying the degradation of organic pollutants such as pesticides and pharmaceutical products under different experimentally manipulated environmental conditions. I also continue to conduct research on subepilimnetic phytoplankton in lakes begun more than 20 years ago at the Experimental Lakes Area in Ontario, Canada and more recently also pursued in lakes elsewhere in Canada and in the Rocky Mountains in Wyoming.
Often my research includes using experimental manipulation to simulate certain types of aquatic disturbances that produce phytoplankton changes, such as those resulting from eutrophication, acidification, climate change, and toxicant stress. For such experimentation, at the University of Kansas I have designed and constructed nearly 200 experimental ponds (0.045 ha), outdoor fiberglass tanks (10 m3), and different types of in situ enclosures for smaller scale experiments within these systems. Research over the 20-year history of our aquatic field station reported in nearly 100 publications has also continually refined the use of experimentally manipulated surrogate ecosystems for aquatic research. In 1991 a 4.5-ha 13-m deep reservoir was constructed at this field station (5 km from campus) in a protected 50-ha watershed to add further variety to this compliment of experimental ecosystems. As one of our projects with this reservoir my students, other faculty and I have been closely monitoring and experimentally manipulating the vertical migration of subepilimnetic phytoplankton populations like those in natural lakes that we also continue to study. The publications listed below represent the variety of the types of research that I have pursued through the years and continue to pursue.
- 2012. "Controls of microalgal biomass and lipid production in municipal wastewater-fed bioreactors" Environmental Progress and Sustainable Energy. 31. 10-16. .
- 2011. "Effects of non-algal turbidity on cyanobacterial biomass in seven turbid Kansas reservoirs" Journal of Lake and Reservoir Management. 27. 6-14. .
- 2010. "The ecology of algal biodiesel production" Trends in Ecology and Evolution. 25. 301-309. .
- 2009. "Development of predictive models for geosmin-related taste and odor in Midwestern U.S. drinking water reservoirs" Water Research. 43. 2829-2840. .
- 2008. "Current state, trend, and spatial variability of sediment in Kansas reservoirs" Sedimentation in Our Reservoirs: Causes and Solutions. 9-24. .
- 2005. "Phytoplankton species richness scales consistently from laboratory microcosms to the world’s oceans" Proceedings of the National Academy of Sciences, USA. 102. 4393-4396. .
- 2005. "An integrated modeling approach to total watershed management: Water quality and watershed assessment of Cheney Reservoir, Kansas, USA" Water, Air, and Soil Pollution. 164. 1-19. .
- 2004. "A deep maximum of green sulphur bacteria (Chlorochromatium aggregatum) in a strongly stratified reservoir" Freshwater Biology. 49. 1337-1354. .
- 2003. "Physical and chemical conditions surrounding the diurnal vertical migration of Cryptomonas spp. (Cryptophyceae) in a seasonally stratified midwestern reservoir (USA)" Journal of Phycology. 39. 855-861. .
- 2003. "Effects of three pharmaceutical and personal care products on natural freshwater algal assemblages" Environmental Science and Technology. 37. 1713-1719. .
- 2002. "Managing taste and odor problems in a eutrophic drinking water reservoir" Lake and Reservoir Management. 18. 318-322. .
- 2000. "Alachlor transformation patterns in aquatic field microcosms under variable oxygen and nutrient conditions" Water Research. 34. 11-19. .
- 1999. "Development of small outdoor microcosms for studying contaminant transformation rates and mechanisms under various water column conditions" Environmental Contamination and Ecotoxicology. 18. 1124-1132. .
- 1998. "Landscape analysis and characterization to support regional environmental assessment" 11 pp. .
- 1998. "Incubating commercial remote sensing products" Progress Report, NASA Headquarters, Earth Science Enterprise, Applications Program. 17 pp. .
- 1994. "Aquatic mesocosms in ecological effects testing: detecting direct and indirect effects of pesticides" Aquatic Mesocosm Studies in Ecological Risk Assessment. edited by . 577-603. .
- 1989. "Use of experimental ponds to assess the effects of a pesticide on the aquatic environment" 41-56. .
- 1982. "The responses of plankton communities in experimental ponds to atrazine, the most heavily used pesticide in the United States" Ecology. 63. 1285-1293. .