B.S. 1994, University of Utah
Ph.D. 1998, Washington State University
Ecology and Evolutionary Biology
Other Cornell Affiliations:
Director, Cornell Isotope Laboratory (COIL)
Director, Office of Undergraduate Biology (OUB)
plant ecology, biogeochemistry, stable isotopes
I am interested in ways that organisms influence the cycling of elements and energy within ecosystems and between ecosystems and the atmosphere. Biogeochemical variation often results from both natural and human-induced environmental changes and human impacts are often an important part of our work. We use a variety of analytical methods with a focus on stable isotopes.
I personally tend to focus on the ecology of arid and semi-arid terrestrial landscapes. However, my students and postdocs work in a variety of aquatic and terrestrial ecosystems. As a group, our interests are very broad across plant, animal, microbial, and ecosystem ecology.
Examples of recent projects include the biogeochemistry of desert soils under global changes including elevated CO2, changes in precipitation, and altered temperature; evolution in place under global change in tropical tree species; impacts of feral hogs in Hawaii; transport of ammonia gas in complex landscapes; physiological ecology of desert bryophytes; physiological impact and global modeling of the influence of ozone on plants; understanding the impacts of the woody encroachment of nitrogen-fixing tree species into C4 arid grasslands; and methane emissions from subtropical grazing systems.
Recent Courses Taught
- BioSM 1610 Ecology and the Marine Environment
- BioEE 3610 Advanced Ecology
- BioEE 4660 Plant Physiological Ecology
- BioEE 4661 Plant Physiological Ecology, Laboratory
- BioEE 6601 Tropical Field Ecology
- BioEE 6602 Graduate Field Course in Ecology
Baker, D. M., K. Kim, J. Andras, and J. P. Sparks. 2011. Light-mediated 15N franctionation in Caribbean gorgonian octocorals. Coral Reefs 30:709-717.
McCalley, C. K., B. D. Strahm, K. L. Sparks A. S. D. Eller, and J. P. Sparks. 2011. The effect of long-term exposure to elevated CO2 on nitrogen gas emissions from Mojave Desert soils. JGR-Biogeosciences 116:G03022, doi:10.1029/2011JG001667.
Sparks, J. P., S. Chandra, L. A. Derry, M. V. Parthasarathy, C. S. Daugherty, and R. Griffin. 2011. The distribution of silicon and germaniaum in tissues of annual blue grass (Poa annua L.): Evidence for differential and active transport from SIMS ion microscopy. Biogeochemistry 104:237-249.
Anderson, J. T., J. P. Sparks, and M. A. Geber. 2010. Phenotypic plasticity despite source-sink population dynamics in a long-lived perennial plant. New Phytologist 188:856-867.
Grote, E. E., J. Belnap, D. Hausman, and J. P. Sparks. 2010. Carbon exchange in biological soil crust communities under differential temperatures and soil water contents: implications for global change. Global Change Biology 16:2763-2774.
Monson, R. K., M. R. Prater, J. Hu, S. P. Burns, J. P. Sparks, K. L. Sparks, and L. E. Scott-Denton. 2010. Tree species effects on ecosystem water-use efficiency in a high-elevation, subalpine forest. Oecologia 162(2):491-504.
McCalley, C. K. and J. P. Sparks. 2009. Abiotic gas formation drives nitrogen loss from a desert ecosystem. Science 326(5954):837-840.
Sparks, J. P. 2009. Foliar incorporation of reactive nitrogen: an important ecological process? Oecologia 159(1):1-13.
Agrawal, A. A., M. Fishbein, R. Jetter, J. Salminen, J. B. Goldstein, A. E. freitag, and J. P. Sparks. 2009. Phylogenetic ecology of leaf surface traits int he milkweeds (Asclepias spp.): chemistry, ecosphysiology, and insect behavior. New Phytologist 183:848-867.
Sparks, J. P., J. M. Roberts, and R. K. Monson. 2003. The uptake of gaseous organic nitrogen by leaves: A significant global nitrogen transfer process. Geophysical Research Letters 30(23):2189.