Bioassay analysis of nutrient and Artemia franciscana effects on trophic interactions in the Great Salt Lake, USA
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14-day microcosm experiments demonstrated the strong interactions between bottom–up and top–down effects of nutrient addition (control, nitrogen, phosphorus, nitrogen + phosphorus) and Artemia franciscana grazing on algae in Great Salt Lake water from Gilbert Bay. Nitrogen addition increased phytoplankton chlorophyll concentrations, while phosphorus addition had no stimulatory effect. A combined N + P treatment was synergistic, increasing both phytoplankton and periphyton >10-fold above controls. Our results suggest that phytoplankton were primarily limited by nitrogen and secondarily limited by phosphorus and that periphyton was colimited by nitrogen and phosphorus. The grazing effect increased as A. franciscana grew from nauplii to adults and by the final day, A. franciscana had markedly reduced both phytoplankton and periphyton abundance in the Control, +N, and +P treatments. Grazing also significantly reduced periphyton in the N + P treatments. Due to high phytoplankton growth rates in the N + P treatment, A. franciscana grazing did not significantly reduce chlorophyll concentrations during the bioassay. However, A. franciscana in the N + P treatment was significantly larger and had greater reproductive output than in the controls, suggesting that the following generation might have exerted greater grazing pressure.
KeywordsGreat Salt Lake Trophic Nitrogen Phosphorus Artemia franciscana Saline
The authors gratefully acknowledge the Utah State University Limnology 4500/5500 class which participated in parts of the bioassay and the USU Aquatic Biogeochemistry Laboratory directed by Dr. Michelle Baker assisted with timely analysis of nutrient samples. The Watershed Sciences Department at Utah State University supported this research. EMO was supported by the NSF EPSCoR grant IIA 1208734 awarded to Utah State University and by the Presidential Doctoral Research Fellowship program at Utah State University. Any opinions, findings, and conclusions or recommendations expressed are those of the authors and do not reflect the views of the National Science Foundation.
- APHA, 1998. Standard Methods for the Examination of Water and Wastewater, 20th ed. American Public Health Association, Washington.Google Scholar
- Belovsky, G. E. & C. Larson, 2002. Brine shrimp population dynamics and sustainable harvesting in the Great Salt Lake, Utah. 2001 Progress Report to the Utah Division of Wildlife Resources, Salt Lake City, Utah. 16pGoogle Scholar
- Belovsky, G. E., D. Stephens, C. Perschon, P. Birdsey, D. Paul, D. Naftz, R. Baskin, C. Larson, C. Mellison, J. Luft, R. Mosley, H. Mahon, J. Van Leeuwen & D. V. Allen, 2011. The Great Salt Lake Ecosystem (Utah, USA): long term data and a structural equation approach. Ecosphere 2: 1–40.CrossRefGoogle Scholar
- Elser, J. J., M. E. S. Bracken, E. E. Cleland, D. S. Gruner, W. S. Harpole, H. Hillebrand, J. T. Ngai, E. W. Seabloom, J. B. Shurin & J. E. Smith, 2007. Global analysis of nitrogen and phosphorus limitation of primary producers in freshwater, marine and terrestrial ecosystems. Ecology Letters 10: 1135–1142.CrossRefPubMedGoogle Scholar
- Gliwicz, Z. M., W. A. Wurtsbaugh & A. Ward, 1995. Brine shrimp ecology in the Great Salt Lake, Utah. Performance Report to the Utah Division of Wildlife Resources, Salt Lake City, Utah. 83p.Google Scholar
- Gruner, D. S., J. E. Smith, E. W. Seabloom, S. A. Sandin, J. T. Ngai, H. Hillebrand, W. S. Harpole, J. J. Elser, E. E. Cleland, M. E. S. Bracken, E. T. Borer & B. M. Bolker, 2008. A cross-system synthesis of consumer and nutrient resource control on producer biomass. Ecology Letters 11: 740–755.CrossRefPubMedGoogle Scholar
- Herbst, D. B., 1998. Potential salinity limitations on nitrogen fixation in sediments from Mono Lake, California. International Journal of Salt Lake Research 7: 261–274.Google Scholar
- Reeve, M. R., 1963. The filter-feeding of Artemia. I. In pure cultures of plant cells. Journal of Experimental Biology 40: 195–205.Google Scholar
- Salm, C. R., J. E. Saros, S. C. Fritz, C. L. Osburn & D. M. Reineke, 2009. Phytoplankton productivity across prairie saline lakes of the Great Plains (USA): a step toward deciphering patterns through lake classification models. Canadian Journal of Fisheries and Aquatic Sciences 66: 1435–1448.CrossRefGoogle Scholar
- SAS Institute Inc., 2013. SAS Institute Inc., Cary, NC.Google Scholar
- Sommer, U., R. Adrian, L. De Senerpont Domis, J. J. Elser, U. Gaedke, B. Ibelings, E. Jeppesen, M. Lurling, J. C. Molinero, W. M. Mooij, E. van Donk & M. Winder, 2012. Beyond the Plankton Ecology Group (PEG) model: mechanisms driving plankton succession. Annual Review of Ecology, Evolution, and Systematics 43: 429–448.CrossRefGoogle Scholar
- Wurtsbaugh, W. A., 1988. Iron, molybdenum and phosphorus limitation of N2 fixation maintains nitrogen deficiency of plankton in the Great Salt Lake drainage (Utah, USA). Verhandlungen der Internationalen Vereingung fur Theoretische und Angewandte Limnologie 23: 121–130.Google Scholar
- Wurtsbaugh, W. A., D. Naftz, & S. Bradt, 2006. Spatial analyses of trophic linkages between basins in the Great Salt Lake. Division of Forestry, Fire & State Lands, Salt Lake City. http://digitalcommons.usu.edu/wats_facpub/543.