Louis A. Kaplan Ph.D.
Senior Research Scientist
970 Spencer Road
Avondale, PA 19311
610.268.2153 x 228
Principal Investigator of the Biogeochemistry group
Adjunct Professor of Biology, Department of Biology, University of Pennsylvania
Participation Member, Marine Estuarine Environmental Sciences (MEES) Graduate Program, University of Maryland
Adjunct Faculty, University of Delaware Center for Critical Zone Research. 2008.
Research Interest & Area of Expertise
Dissolved organic matter biogeochemistry, aquatic microbial ecology, and nutrient cycling.
B.A., Environmental Sciences, 1972. Franklin and Marshall College, Lancaster, Pennsylvania.
M.S., Ecology, 1974. University of California, Davis, California.
Ph.D., Biology (Limnology), 1980. University of Pennsylvania, Philadelphia, Pennsylvania.
Curator, Division of Environmental Research, Stroud Water Research Center, Academy of Natural Sciences of Philadelphia. July 1996 - October 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. September 1974 - June 1975.
Current & Recent Research
Principal Investigator. Hydrologic regulation of dissolved organic matter biogeochemistry from forests through river networks. National Science Foundation EAR 0450331. May 2005–April 2010. Each year, massive amounts of organic carbon, in the form of dissolved molecules, are transported to the oceans of the world by rivers. The source of most of that carbon is the upper layer of soils within small watersheds, and the movement of water through soils controls organic carbon delivery from the landscape to streams. Standing on the streambank, we look both upslope and downstream, focusing on the interactions of water movement and organic carbon supply, investigating processes within the hillslope soils, individual stream reaches, and the entire river network. This collaborative proposal will integrate dynamic mathematical models that describe organic carbon movement, transformation, quantity and quality in terrestrial and aquatic environments and will generate the first model that links the water cycle and the carbon cycle of river catchments. Collaborators: J. Denis Newbold and Anthony K. Aufdenkampe, Stroud Water Research Center, and George M. Hornberger, University of Virginia.
Principal Investigator. The application of scaling rules to energy flow in stream ecosystems. National Science Foundation DEB 0516516. August 2005-September 2010. Naturally occurring organic molecules dissolved in water constitute the largest pool of organic matter in aquatic ecosystems. Within streams and rivers, molecules that originate in terrestrial vegetation and are modified within soils and groundwater by microorganisms during movement to the channel, are the dominant source of organic matter. These terrestrially derived molecules in transport downstream contribute to the biologically useful chemical energy present in freshwater and coastal marine environments. Our research uses a novel application of stable isotopes to quantify those contributions throughout a drainage network, and we frame our investigations within the context of scaling rules that facilitate the transfer of information from one habitat or system to others. We have grown young deciduous trees in an atmosphere enriched with the stable isotope of carbon, harvested and composted the trees, and extracted the compost to prepare a leachate of complex, microbially modified molecules, and are following the fate of those organic molecules in small laboratory reactors and microcosms. We plan to perform whole stream releases of these molecules in 1st through 5th order streams. Combining scaling rules derived from the knowledge of how streams “grow” as they flow towards the ocean with scaling rules associated with nutrient uptake in streams, allows us to test hypotheses concerning how organic molecules are used for energy within a stream network. Collaborators: J. Denis Newbold and Anthony K. Aufdenkampe, Stroud Water Research Center, Robert H. Findlay, University of Alabama, and Peggy H. Ostrom, Michigan State University.
Principal Investigator. Long Term Research in Environmental Biology (LTREB): Stream ecosystem structure and function within a maturing deciduous forest. National Science Foundation DEB 0424681. June 2004-May 2009. This project addresses long-term changes in the ecosystem of a stream located an agricultural region of southeastern Pennsylvania. Stroud Water Research Center scientists will focus on segments of White Clay Creek, a designated National Wild and Scenic River System watershed, that flow through: a 60- to 100-year-old forest; a 20-year-old reforested meadow; and a permanent meadow. Because scientists do not fully understand either the short-term dynamics or the long-term stability of stream ecosystems, this study will measure (1) the benefits of a forested stream compared to a meadow stream and (2) the time frames needed to reach milestones for stream restoration and reforestation projects. Scientists with expertise in chemistry, biology, and ecosystem modeling will combine efforts to sample, analyze, and describe the composition and activities of biological communities in the stream and its watershed. The research on White Clay Creek will provide an evaluation of best management practices in agriculture and a time frame for ecosystem recovery as a result of those practices. Stroud Water Research Center educational and outreach programs will then convey these findings to farmers and landowners for direct implementation, to public officials and community groups for policy considerations, and to the teachers and students who will inherit the watershed. Collaborators: J. Denis Newbold and Anthony K. Aufdenkampe, Thomas L. Bott, John K. Jackson, Bernard W. Sweeney, Charles L. Dow, Stroud Water Research Center.
Principal Investigator. Biofilm ecology within the East Park Reservoir distribution system, Philadelphia Water Department, and the efficacy of control strategies. Philadelphia Water Department. May 2006-June 2008. Microorganisms in drinking water distribution systems can impact water quality and create regulatory concerns for utilities that involve disinfection residuals, densities of coliforms, and concentrations of disinfection by products. While there are microorganisms suspended in distribution water, most of the organisms are attached to the surfaces of pipes in biofilms. Knowledge of the ecology of the distribution system biofilm community composition is important to identifying effective treatment strategies. The City of Philadelphia Water Department (PWD) obtains water from the Delaware River and Schuylkill River. A portion of the treated waters from these sources are mixed and stored in the East Park Reservoir. Our research focuses on microbial biofilm growth within the East Park Reservoir distribution system and its control. Our objectives, divided into two research areas, are to assess the ecology of the distribution system biofilm and to identify effective treatment regimes to control biofilm growth. We are using molecular techniques in microbial ecology to identify the Bacteria and Archaea present, find out where they come from, determine whether they rely on organic carbon for growth, assess the stability of the community composition, and determine whether they harbor indicator organisms. Ultimately, we will test different disinfectant agents for their ability to inactivate distribution system biofilms and assess the impact on biofilm growth of reducing organic carbon concentrations. Collaborators: David A. Stahl, University of Washington and Anne K. Camper, Montana State University.
Co-Principal Investigator. Seston contributions to metabolism across longitudinal ecosystems (SCALE) – Dynamics of organic particles in river networks. National Science Foundation DEB 0543526. April 2006-March 2010. The River Continuum Concept (RCC) predicted that the transport of partially processed materials from upstream are a major bioenergetic influence and energy source for downstream communities. In the intervening decades this prediction has not been tested. Here we look back to the RCC, and at the same time look forward through the incorporation of major technical and theoretical advances, to test our overarching hypothesis that metabolism in streams and rivers is subsidized by particulate organic carbon (POC) transported from upstream. We submit that from the perspectives of the role of rivers in global carbon cycling and the wisdom of preserving headwater streams, it is important to quantify the dependence of downstream ecosystems upon POC from upstream and to know what fraction of the respiration at a given location in a river network is fueled by POC transported 1, 10, 100 or 1000 km from where it enters the river. Furthermore, the location where POC is mineralized within a fluvial system relative to the site of photosynthetic fixation has enormous consequences to aquatic ecosystem energy balance, watershed management of headwater streams, and quantifying net terrestrial carbon sinks. Collaborators: J. Denis Newbold and Anthony K. Aufdenkampe, Stroud Water Research Center, Aaron Packman, Northwestern University, and James McNair, Academy of Natural Sciences of Philadelphia.
Co-Principal Investigator. Long-Term Research in Environmental Biology (LTREB): Dynamics of stream ecosystem responses across gradients of reforestation and changing climate in a tropical dry forest. National Science Foundation DEB 0516516. December 2005-November 2010. The Guanacaste Conservation Area (ACG) in northwestern Costa Rica with streams that flow to both the Pacific and Caribbean is a site for LTREB research in Central America. The ACG is also the site of the largest forest restoration project in the tropics. In this research we are testing hypotheses regarding the response of stream ecosystems to large-scale, passive reestablishment of tropical dry forests, as well as to steep moisture gradients that define much of the character of the ACG flora and fauna. The biogeochemistry section is addressing two questions: (1) How does the physicochemical character of tropical streams respond to moisture and forest cover gradients, and to near-term and long-term phenomena such as forest restoration and climatic variation and change; and (2) What is responsible for the unusually low dissolved organic carbon concentrations observed in the ACG streams under baseflow conditions and how will this change with reforestation? Collaborators: John K. Jackson, J. Denis Newbold, Anthony K. Aufdenkampe, and Thomas L. Bott, Stroud Water Research Center, Julio Calvo, Technical University of Costa Rica, and Arturo Sanchez-Azifeifa, University of Alberta.
Co-Principal Investigator. Scientific and Educational Aspects of Water Quality and Stream Health in Eastern Pennsylvania. NASA. 2007-2008. In 1967, Buck County of southeastern Pennsylvania launched a 3-year program to assess the water quality and health of its stream and river ecosystems. That study established a baseline to measure the effects of population growth and development. The Stroud Water Research Center has begun to reproduce and upgrade portions of the original study to : (1) assess current water quality and stream health; (2) provide additional new data to help public officials protect the region’s water; and (3) provide an enhanced baseline to assess future changes. Collaborators: Bernard W. Sweeney, Principal Investigator; Co-Principal Investigators, J. Denis Newbold, Anthony K. Aufdenkampe, John K. Jackson, and Thomas L. Bott, Stroud Water Research Center.
Co-Principal Investigator. Measuring watershed health: training conservation planners how to use biophysical tools for monitoring streams in temperate and neo-tropical ecosystems. Gordon and Betty Moore Foundation. 2006. This project involved an expedition to sites within the Madre de Dios and Tambopata rivers of Peru. The project goals were to: (1) establish a baseline of scientific data on water quality, stream biodiversity, and stream health that would serve as the foundation for understanding and sustaining on-going conservation efforts in the region; (2) create, test, and implement education programs from people of the region. Collaborators: Bernard W. Sweeney, Principal Investigator; Co-Principal Investigators, J. Denis Newbold, Anthony K. Aufdenkampe, John K. Jackson, and Thomas L. Bott, Stroud Water Research Center.
Co-Principal Investigator. Water quality monitoring in the source water areas for New York City: an integrative watershed approach. NY State DEC and U.S. EPA. 2003-2006. This monitoring program involved analyzing physical, chemical, and biological indicators to measure, quantify, and determine source and impacts of contaminants throughout the watersheds that provide drinking water to New York City. The project enhanced on-going monitoring project and provided an additional baseline of information to assess changes in water quality in response to changes in land cover, land use, and the implementation of best management practices for mitigating both point and non-point source pollution. Collaborators: Bernard W. Sweeney, Principal Investigator; Co-Principal Investigators, J. Denis Newbold, Anthony K. Aufdenkampe, John K. Jackson, and Thomas L. Bott, Stroud Water Research Center.
Mosher, J.J., L.A. Kaplan, D.C. Podgorski, A.M. McKenna, and A.G. Marshall. 2015. Longitudinal shifts in dissolved organic matter chemogeography and chemodiversity within headwater streams: a river continuum reprise. Biogeochemistry, Volume 124, Issue 1 (2015), pp. 371-385. DOI: 10.1007/s10533-015-0103-6
Sleighter, R.L., R.M. Cory, L.A. Kaplan, H.A.N. Abdulla, and P.G. Hatcher. 2014. A coupled geochemical and biogeochemical approach to characterize the bioreactivity of dissolved organic matter from a headwater stream. Journal of Geophysical Research: Biogeosciences, 119 (8):1520-1537. DOI: 10.1002/2013JG002600
Mosher, J.J., B. Bowman, E.L. Bernberg, O. Shevchenko, J. Kan, J. Korlach, and L.A. Kaplan. 2014. Improved performance of the PacBio SMRT technology for 16S rDNA sequencing. Journal of Microbiological Methods 104 (2014) 59–60. DOI: 10.1016/j.mimet.2014.06.012
Mei, Y., G.M. Hornberger, L.A. Kaplan, J.D. Newbold, and A.K. Aufdenkampe. 2014. The delivery of dissolved organic carbon from a forested hillslope to a headwater stream in southeastern Pennsylvania, USA, Water Resour. Res., 50, DOI:10.1002/2014WR015635
Sawyer, A.H., L.A. Kaplan, O. Lazareva, and H.A. Michael. 2014. Hydrologic dynamics and geochemical responses within a floodplain aquifer and hyporheic zone during Hurricane Sandy. Water Resources Research, 50 (6): 4877–4892. DOI: 10.1002/2013WR015101
Bengtsson, M.M., K. Wagner, N.R. Burns, E.R. Herberg, W. Wanek, L.A. Kaplan, and T.J. Batting. 2014. No evidence of aquatic priming effects in hyporheic zone microcosms. Scientific Reports, DOI: 10.1038/srep05187
Tsang, Y., G. M. Hornberger, L. A. Kaplan, J. D. Newbold, and A. K. Aufdenkampe. 2014. A variable source area for groundwater evapotranspiration: impacts on modeling stream flow. Hydrol. Process. 28, 2439-2450. DOI: 10.1002/hyp.9811
Mosher, J., E.L. Bernberg, O. Shevchenko, J. Kan, and L.A. Kaplan. 2013. Efficacy of a 3rd generation high-throughput sequencing platform for analyses of 16S rRNA genes from environmental samples. Journal of Microbiological Methods 95(2):175-181. DOI: 10.1016/j.mimet.2013.08.009
McLaughlin, C. and L.A. Kaplan. 2013. Biological lability of dissolved organic carbon in stream water and contributing terrestrial sources. Freshwater Science 32(4):1219-1230. DOI: 10.1899/12-202.1
Richardson, D.C., J.D. Newbold, A.K. Aufdenkampe, P.G. Taylor, and L.A. Kaplan. 2013. Measuring heterotrophic respiration rates of suspended particulate organic carbon from stream ecosystems. Limnol. Oceanogr.: Methods 11, 2013, 247–261. DOI: 10.4319/lom.2013.11.247.
Mei, Y., G. M. Hornberger, L. A. Kaplan, J. D. Newbold, and A. K. Aufdenkampe. 2012. Estimation of dissolved organic carbon contribution from hillslope soils to a headwater stream. Water Resources Research, Vol. 48, W09514, DOI: 10.1029/2011WR010815
Cory, R. M. and L. A. Kaplan. 2012. Biological lability of streamwater fluorescent dissolved organic matter. Limnology and Oceanography, 57(5):1347–1360. DOI: 10.4319/lo.2013.58.1.0428
Battin, T. J., S. Luyssaert, L. A. Kaplan, A. K. Aufdenkampe, A. Richter and L. J. Tranvik. 2009. The boundless carbon cycle. Nature Geosciences 2: 598-600, DOI: 10.1038/ngeo618
Richardson, D. C., L. A. Kaplan, J. D. Newbold and A. K. Aufdenkampe. 2009. Temporal dynamics of seston: A recurring nighttime peak and seasonal shifts in composition in a stream ecosystem. Limnology and Oceanography 54(1): 344–354. DOI: 10.4319/lo.2009.54.1.0344
Findlay, R. H., C. Yeates, M. A. J. Hullar, D. A. Stahl. and L. A. Kaplan. 2008. Biome level biogeography in streambed microbiota. Applied and Environmental Microbiology 74(10):3014-3021. Request PDF.
Battin, T.J., L. A. Kaplan, S. Findlay, C. S. Hopkinson, E. Marti, A. I. Packman, J. D. Newbold, and F. Sabater. 2008. Biophysical controls on dissolved organic carbon in fluvial networks. Nature Geosciences 1: 95-100. Request PDF.
Kaplan, L. A., T. N. Wiegner, J. D. Newbold, P. H. Ostrom, and H. Gandhi. 2008. Untangling the complex issue of dissolved organic carbon uptake: a stable isotope approach. Freshwater Biology 53:855–864. Request PDF.
Kaplan, L. A., J. D. Newbold, D. J. Van Horn, C. L. Dow, A. K. Aufdenkampe, and J. K. Jackson. 2006. Organic matter transport in New York City drinking-water-supply watersheds. Journal of the North American Benthological Society 25:912-927. DOI: 10.1899/0887-3593(2006)025[0912:OMTINY]2.0.CO;2
Kim, S., L. A. Kaplan, and P. G. Hatcher. 2006. Biodegradable dissolved organic matter in a temperate and a tropical stream determined from ultra-high resolution mass spectrometry. Limnology and Oceanography 51:1054-1063. Request PDF.
Hullar, M. A. J., L. A. Kaplan, and D. A. Stahl. 2006. Recurring seasonal dynamics of microbial communities in stream habitats. Applied and Environmental Microbiology 72:713-722. Request PDF.
Newbold, J. D., T. L. Bott, L. A. Kaplan, C. L. Dow, L. A. Martin, D. J. Van Horn, and A. A. de Long. 2006. Uptake of nutrients and organic C in streams in New York City drinking-water-supply watersheds. Journal of the North American Benthological Society 25:998-1017.
Kratzer, E. B., J. K. Jackson, D. B. Arscott, A. K. Aufdenkampe, C. L. Dow, L. A. Kaplan, J. D. Newbold, and B. W. Sweeney. 2006. Macroinvertebrate distribution in relation to land use and water chemistry in New York City drinking-water-supply watersheds. Journal of the North American Benthological Society 25:954-976.
Sweeney, B. W., D. B. Arscott, C. L. Dow, J. G. Blaine, A. K. Aufdenkampe, T. L. Bott, J. K. Jackson, L. A. Kaplan, and J. D. Newbold. 2006. Enhanced source-water monitoring for New York City: summary and perspective. Journal of the North American Benthological Society 25:1062-1067.
Wiegner, T. N., L. A. Kaplan, J. D. Newbold, and P. H. Ostrom. 2005. Synthesis of a 13C-labeled tracer for stream DOC: labeling tulip poplar carbon with 13CO2. Ecosystems 8:501-511. Request PDF.
Volk, C., L. A. Kaplan, J. Robinson, B. Johnson, L. Wood, H. W. Zhu, and M. LeChevallier. 2005. Fluctuations of dissolved organic matter in a river used for drinking water and impacts on conventional treatment plant performance. Environmental Science and Technology 39:4258-4264. Request PDF.
Frazier, S. W., L. A. Kaplan, and P. G. Hatcher. 2005. Molecular characterization of biodegradable dissolved organic matter using bioreactors and [12C/13C] tetramethylammonium hydroxide thermochemolysis GC-MS. Environmental Science and Technology 39:1479-1491. Request PDF.
Wiegner, T. N., L. A. Kaplan, J. D. Newbold, and P. H. Ostrom. 2005. Contribution of dissolved organic C to stream metabolism: a mesocosm study using 13C-enriched tree-tissue leachate. Journal North American Benthological Society 24:48-67. Request PDF.
Kim, S., L. A. Kaplan, R. Benner, and P. G. Hatcher. 2004. Hydrogen-deficient molecules in natural riverine water samples — evidence for the existence of black carbon in DOM. Marine Chemistry 92:225-234. Request PDF.
Gandhi, H., T. N. Wiegner, P. H. Ostrom, L. A. Kaplan, and N.E. Ostrom. 2004. Isotopic (13C) analysis of dissolved organic carbon in stream water using an elemental analyzer coupled to a stable isotope ratio mass spectrometer. Rapid Communications in Mass Spectrometry 18:903-906. Request PDF.
Battin, T. J., L. A. Kaplan, J. D. Newbold, X. Cheng, and C. Hansen. 2003. Effects of current velocity on the nascent architecture of stream microbial biofilms. Applied and Environmental Microbiology 69:5443-5452.
Battin, T. J., L. A. Kaplan, J. D. Newbold, C. Hansen. 2003. Contributions of microbial biofilms to ecosystem processes in stream mesocosms. Nature 426: 439-442. Request PDF.
Battin, T. J., L. A. Kaplan, J. D. Newbold, and S. P. Hendricks. 2003. A mixing model analysis of stream solute dynamics and the contribution of a hyporheic zone to ecosystem function. Freshwater Biology 48:995-1014. Request PDF.
Cheng, X., and L. A. Kaplan. 2003. Simultaneous analyses of neutral carbohydrates and amino sugars in freshwaters with HPLC-PAD. Journal of Chromatographic Science 41:434-438. Request PDF.
Frazier, S. W., K. O. Nowack, K. M. Goins, F. S. Cannon, L. A. Kaplan, and P. G. Hatcher. 2003. Characterization of organic matter from natural waters using tetramethylammonium hydroxide thermochemolysis GC-MS. Journal of Analytical and Applied Pyrolysis 70:99-128.
Kaplan, L. A., and J. D. Newbold. 2003. The role of monomers in stream ecosystem metabolism. pp. 97-119 in S. E. G. Findlay and R. L. Sinsabaugh, eds. Aquatic Ecosystems — Interactivity of Dissolved Organic Matter. Academic Press.
Meyer, J. L., L. A. Kaplan, J. D. Newbold, D. L. Strayer, C. J. Woltemade, J. D. Zelder, R. Beilfuss, Q. Carpenter, R. Semlitsch, M. C. Watzin, and P. H. Zedler. 2003. Where Rivers Are Born: The Scientific Imperative for Defending Small Streams and Wetlands. Sierra Club and American Rivers. Request PDF.
Aiken, G., L. A. Kaplan, and J. Weishaar. 2002. Assessment of relative accuracy in the determination of organic matter concentrations in aquatic systems. Journal of Environmental Monitoring. 4:70-74. Request PDF.
Volk, C., L. Wood, B. Johnson, J. Robinson, H.W. Zhu, and L. Kaplan. 2002. Monitoring dissolved organic carbon in surface and drinking waters. Journal of Environmental Monitoring 4:43-47. Request PDF.
Cheng, X., and L. A. Kaplan. 2001. Improved analysis of dissolved carbohydrates in stream water with HPLC-PAD. Analytical Chemistry 73:458-461.
Standley, L. J., L. A. Kaplan, and D. Smith. 2000. Molecular tracers of organic matter sources to surface water resources. Environmental Science and Technology.
Kaplan, L. A. 2000. A broad-scale comparison of DOC methodologies. J. American Water Works Association 92:149-156.
Kaplan, L. A. and A. E. Konopka. 2000. Freshwater Microbiology, pp. 438-450. In: Encyclopedia of Microbiology, Second Edition, J. Lederberg, ed. Academic Press, San Diego.
Kaplan, L. A. and J. D. Newbold. 2000. Surface and subsurface dissolved organic carbon. pp. 237-258 In: Streams and Ground Waters, J. B. Jones and P. J. Mulholland, eds. Academic Press.
Gremm, T. J. and L. A. Kaplan. 1998. Dissolved carbohydrate concentration, composition, and bioavailability to microbial heterotrophs in stream water. Acta hydrochim. hydrobiol. 26 (3): 167-171.
Pusch, M., D. Fiebig, I. Brettar, H. Eisenmann, B. K. Ellis, L. A. Kaplan, M. A. Lock, M. W. Naegeli, and W. Traunspurger. 1998. The role of micro-organisms in the ecological connectivity of running waters. Freshwater Biology 40:453-495.
Standley, L. J. and L. A. Kaplan. 1998. Isolation and analysis of lignin-derived phenols in aquatic humic substances: improvements on the procedures. Organic Geochemistry. 28 (11): 689-697.
Gremm, T. J. and L. A. Kaplan. 1997. Dissolved carbohydrates in stream water determined by HPLC and pulsed amperometric detection. Limnology and Oceanography 42:385-393.
Volk, C. J. C. B. Volk, and L. A. Kaplan. 1997. The chemical composition of biodegradable dissolved organic matter in streamwater. Limnology and Oceanography 42:39-44.
Newbold, J. D., T. L. Bott, L. A. Kaplan, B. W. Sweeney, and R. L. Vannote. 1997. Organic matter dynamics in White Clay Creek, Pennsylvania, U.S.A.. Pages 46 - 50 in J. R. Webster and J. L. Meyers (editors). Stream organic matter budgets. Journal of the North American Benthological Society 16:3-161.
Kaplan, L. A. and J. D. Newbold. 1995. Measurement of streamwater biodegradable dissolved organic carbon with a plug-flow bioreactor. Water Research 29:2696-2706.
Newbold, J. D., B. W. Sweeney, J. K. Jackson, and L. A. Kaplan. 1995. Concentrations and export of solutes from six mountain streams in northwestern Costa Rica. Journal of the North American Benthological Society 14:21-37. Request PDF.
Kaplan, L. A., L. J. Standley, and J. D. Newbold. 1995. Impact on water quality of high and low density applications of spent mushroom substrate to agricultural lands. Compost Science & Utilization 3:55-63.
Kaplan, L. A. 1994. A field and laboratory procedure to collect, process, and preserve freshwater samples for dissolved organic carbon analysis. Limnology and Oceanography 39:1470-1476.
Jackson, J. K., B. W. Sweeney, T. L. Bott, J. D. Newbold, and L. A. Kaplan. 1994. Transport of Bacillus thuringiensis var. and its effect on drift and benthic densities of nontarget macroinvertebrates in the Susquehanna River, Northern Pennsylvania. Canadian Journal of Fisheries and Aquatic Sciences. 51:295-314.
Kaplan, L. A., D. J. Reasoner, and E. W. Rice. 1994. A survey of biodegradable organic matter in U.S. drinking waters. Journal American Water Works Association 86: 121-132.
Kaplan, L. A., F. Ribas, J.-C. Joret, C. Volk, J. Frias, and F. Lucena. 1993. An immobilized biofilm reactor for the measurement of biodegradable organic matter in drinking water: Validation and field test. Proceedings of the Water Quality Technology Conference, Miami, FL, pp. 1457-1475.
LeChevallier, M. W., N. E. Shaw, L. A. Kaplan, and T. L. Bott. 1993. Development of a rapid assimilable organic carbon method for water. Applied and Environmental Microbiology 59:1526-1531.
Kaplan, L. A., T. L. Bott, and D. J. Reasoner. 1993. Evaluation and simplification of the assimilable organic carbon nutrient bioassay for bacterial growth in drinking water. Applied and Environmental Microbiology 59:1532-1539.
Bott, T. L., and L. A. Kaplan. 1993. Persistence of a surrogate for a genetically engineered cellulolytic microorganism and effects on aquatic community and ecosystem properties: mesocosm and stream comparisons. Canadian Journal of Microbiology 39:686-700.
Bott, T.L. and L.A. Kaplan. 1992. Habitat specific differences in persistence and effects of introduced cellulolytic bacteria used as surrogates for GEMS, pp. 135-139. In: J.E. Harvey, ed. Proceedings of the 4th Investigators meeting for EPA's Biotechnology-Biological Control Agent Risk Assessment Research Program, Rept. No. EPA/600/R-92/147. U.S. EPA. Gulf Breeze, FL.
Kaplan, L. A., M. W. LeChevallier, and T. L. Bott. 1992. Evaluation of utility laboratory personnel performance of a standardized AOC technique. Proceedings of Water Quality Technology Conference, Orlando, FL, pp. 1169-1185.
Kaplan, L. A., T. L. Bott, and J. K. Bielicki. 1992. Assessment of [3H]thymidine incorporation into DNA as a method to determine bacterial productivity in streambed sediments. Applied and Environmental Microbiology 58:3614-3621.
Kaplan, L. A., D. J. Reasoner, E. W. Rice, and T. L. Bott. 1992. A survey of assimilable organic carbon, biodegradable organic carbon, and coliform growth response in drinking waters throughout the United States. Revue des Sciences de l'Eau 5:207-224.
Kaplan, L. A., and J. D. Newbold. 1993. Sources and biogeochemistry of terrestrial dissolved organic carbon entering streams, pp.139-165. In: T. E. Ford (ed.), Aquatic Microbiology: An Ecological Approach. Blackwell Scientific Publications Inc.
Kaplan, L. A. 1992. Comparison of high-temperature and persulfate oxidation methods for the determination of dissolved organic carbon in freshwaters. Limnology and Oceanography 37:1119-1125.
Bott, T. L., and L. A. Kaplan. 1991. Selection of surrogates for a genetically engineered microorganism with cellulolytic capability for ecological studies in streams. Canadian Journal of Microbiology 37:848-857.
Bott, T. L., and L. A. Kaplan. 1990. Potential for protozoan grazing of bacteria in streambed sediments. Journal of the North American Benthological Society 9:336-345.
Kaplan, L. A., and T. L. Bott. 1990. Modifications to simplify an AOC bioassay for routine use by utilities monitoring bacterial regrowth potential in water distribution systems. Proceedings Water Quality Technology Conference, Philadelphia, Pennsylvania. pp. 1031-1042.
Kaplan, L. A. and T. L. Bott. 1990. Nutrients for bacterial growth in drinking water: Bioassay Evaluation, EPA Report No. EPA/600/S2-89/030. U.S. EPA Cincinnati.
Bott, T. L. and L. A. Kaplan. 1990. Cellulolytic bacteria as surrogates for genetically engineered microorganisms: Microcosm studies of persistence and effects in streambed sediments, pp. 139-143. In ORD Biotechnology Risk Assessment Program, ed. Review of Progress in the Biotechnology-Microbial Pest Control Agent Risk Assessment Program, Rept. No. EPA/600/9-90/029. U.S. EPA, Washington.
Kaplan, L. A., and T. L. Bott. 1989. Measurement of assimilable organic carbon in water distribution systems by a simplified bioassay technique. Proceedings Water Quality Technology Conference, St. Louis, Missouri. pp. 475-498.
Bott, T. L. and L. A. Kaplan. 1989. Densities of benthic protozoa and nematodes in a piedmont stream. Journal of the North American Benthological Society 8:187-196.
Kaplan, L. A., and T. L. Bott. 1989. Diel fluctuations in bacterial activity on streambed substrata during vernal algal blooms: Effects of temperature, water chemistry, and habitat. Limnology and Oceanography 34:718-733.
Kaplan, L.A., and T.L. Bott. 1985. Acclimation of stream-bed heterotrophic microflora: metabolic responses to dissolved organic matter. Freshwater Biology 15:479-492.
Bott, T.L. and L.A. Kaplan. 1985. Bacterial biomass, metabolic state, and activity in stream sediments: Relation to environmental variables and multiple assay comparisons. Applied and Environmental Microbiology 50:508-522.
Kaplan, L.A., and T.L. Bott. 1985. Adenylate energy charge in streambed sediments. Freshwater Biology 15:133-138.
Bott, T.L. and L.A. Kaplan, and F.T. Kuserk. 1984. Benthic bacterial biomass supported by streamwater dissolved organic matter. Microbial Ecology 10:335-344.
Kuserk, F.T., L.A. Kaplan, and T.L. Bott. 1984. In situ measures of dissolved organic carbon flux in a rural stream. Canadian Journal of Fisheries and Aquatic Sciences, 41:964-973.
Kaplan, L.A., and T.L. Bott. 1983. Microbial heterotrophic utilization of dissolved organic matter in a piedmont stream. Freshwater Biology 13:363-377.
Kaplan, L.A., and T.L. Bott. 1982. Diel fluctuations of DOC generated by algae in a piedmont stream. Limnology and Oceanography 27:1091-1100.
Kaplan, L.A., R.A. Larson, and T.L. Bott. 1980. Patterns of dissolved organic carbon in transport. Limnology and Oceanography 25:1034-1043.
Leonard, R.L., L.A. Kaplan, J.F. Elder, R.N. Coates, and C.R. Goldman. 1979. Nutrient transport in surface runoff from a subalpine watershed, Lake Tahoe basin, California. Ecological Monographs 49:281-310.
Perkins, M.A. and L.A. Kaplan. 1978. Epilithic periphyton and detritus studies in a subalpine stream. Hydrobiologia 57:103-109.
Recent Presentations – Primary Author
Intra-and Inter-biome tests of functional redundancy: Can bacterial heterotrophs from one stream metabolize the dissolved organic matter present in the water from another stream? L. A. Kaplan. Oral presentation at 9th International Symposium on Microbial Ecology, 26-31 August, 2001, Amsterdam, The Netherlands.
The role of monomers in stream ecosystem metabolism. L. A. Kaplan and J. D. Newbold. NSF-funded Symposium on Integrating Approaches to Microbial-DOC Trophic Linkages. Member of the Scientific Committee and Presenter. May 2000. Institute of Ecosystem Studies.
Dissolved organic carbon dynamics and biodegradation in diverse stream ecosystems. Engler-Bunte Institute, University of Karlsruhe. September 2000.
Rutgers University, Ecology and Evolution Graduate Group. Variability in terrestrially derived DOM and its influence on microbial populations in streams. November 2000.
DOM/bacterial interactions in streams: the interaction of lability, scaling, and hydrodynamics L. A. Kaplan and J. D. Newbold. American Society for Limnology and Oceanography Aquatic Sciences Meeting, Research Across Boundaries, Copenhagen, June 5-9, 2000. Invited speaker.
The influence of temporal and spatial variability in the flux of DOC in stream ecosystems on the biomass and activity of bacterial communities. Plenary Session: Dynamics in Microbial Communities of Lotic Systems. L. A. Kaplan, T. J. Battin, T. J. Gremm, and J. D. Newbold. European Marine Microbiology Symposium and International Workshop on the Measurement of Microbial Activities in the Carbon Cycle in Aquatic Environments. Noordwijkerhout, The Netherlands. September 17-22, 2000. Member of the International Scientific Committee and Invited Lecturer.
Honors & Awards
Trustee's Scholarship, Franklin and Marshall College 1971
B.A. awarded cum laude 1972
NSF pre-doctoral graduate fellowship 1972 - 1974; 1975 - 1976
Shell Companies Foundation fellowship 1976 - 1980
NSF grant for improving doctoral dissertation research in the field sciences DEB 77-12902, 1977
Division of Environmental Research 1988 Award for Scientific Merit
Fellow American Academy of Microbiology July 1995
American Association for the Advancement of Science
American Society for Microbiology
American Society of Limnology and Oceanography
American Water Works Association
North American Benthological Society
Editorial Board Applied and Environmental Microbiology 1997 – 1999
Panel member for National Science Foundation and U.S. Environmental Protection Agency
Chairman, Joint Task Group for Section 9217 on Assimilable Organic Carbon published in Standard Methods for the Examination of Water and Wastewater, 1992 – present
Member, Joint Task Group for Section 5310 on Total Organic Carbon published in Standard Methods for the Examination of Water and Wastewater. 1996– present
Ad hoc reviewer, Canadian Journal of Fisheries and Aquatic Sciences, Ecology, Limnology and Oceanography, Freshwater Biology, Freshwater Ecology, Journal American Water Works Association, Journal North American Benthological Society, Revue des Sciences de l'Eau, National Science Foundation, Hudson River Foundation, and National Geographic Society.