Louis Kaplan, Ph.D.

500 500 Stroud Water Research Center

Research Scientist Emeritus

  • Affiliate Faculty, Delaware Environmental Institute, University of Delaware

970 Spencer Road, Avondale, PA 19311

Interests and Expertise

Dissolved organic matter biogeochemistry, aquatic microbial ecology, and nutrient cycling.

Google Scholar


  • Ph.D., Biology (Limnology), University of Pennsylvania, Philadelphia, Pennsylvania.
  • M.S., Ecology, University of California, Davis, California.
  • B.A., Environmental Sciences, Franklin and Marshall College, Lancaster, Pennsylvania.

Professional Experience

  • Research Scientist Emeritus, Stroud Water Research Center, 2018–present.
  • Director, Ecosystem Science Cluster, Division of Environmental Science, National Science Foundation, 2015–2018.
  • Senior Research Scientist, Stroud Water Research Center, 1999–2017.
  • Curator, Division of Environmental Research, Stroud Water Research Center, Academy of Natural Sciences of Philadelphia, 1996–1999.
  • Assistant Curator, Division of Environmental Research, Stroud Water Research Center, Academy of Natural Sciences of Philadelphia, 1988–1992.
  • Research Associate, Division of Environmental Research, Stroud Water Research Center, Academy of Natural Sciences of Philadelphia, 1980–1988.
  • Post Graduate Research Scientist III, University of California, Davis, California, 1974–1975.


Recurring seasonal dynamics of microbial communities in stream habitats

Hullar, M. A. J., L. A. Kaplan, and D. A. Stahl. 2006. Applied and Environmental Microbiology 72:713–722.

Synthesis of 13C-labeled tracer for stream DOC: labeling tulip poplar carbon with 13CO2

Wiegner, T.N., L.A. Kaplan, J.D. Newbold, and P.H. Ostrom. 2005. Ecosystems 8:501–511.

Fluctuations of dissolved organic matter in river used for drinking water and impacts on conventional treatment plant performance

Volk, C., L.A. Kaplan, J. Robinson, B. Johnson, L. Wood, H.W. Zhu, and M. LeChevallier. 2005. Environmental Science and Technology 39(11):4258–4264.

Contribution of dissolved organic carbon to stream metabolism estimated with 13C-enriched tree tissue leachate

Wiegner, T.N.,L.A. Kaplan, J.D. Newbold, and P.H. Ostrom. 2005. Journal North American Benthological Society 24:48–67.

The role of organic matter in structuring microbial communities

Kaplan, L., M. Hullar, L. Sappelsa, D. Stahl, P. Hatcher, and S. Frazier. 2005. American Water Works Association, Denver, Colorado.

See all publications by Stroud Center authors

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