Investigation of the effects of hillslope properties on carbon and nitrogen biogeochemistry in a semi-arid New Mexico ecosystem

CHED 1100

Michael J. Pullin, mpullin@nmt.edu1, Margaret Tammaro, tammarom@lafayette.edu2, Yaika Echevarría Román3, Randall D. John4, Steven D. Scholle, and Thomas L. Kieft, tkieft@nmt.edu5. (1) Department of Chemistry, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801, (2) Department of Chemistry, Lafayette College, Hugel Science Center, Easton, PA 18042, (3) Universidad Metropolitana, San Juan, PR 00928, (4) Diné College, Shiprock, NM 87420, (5) Department of Biology, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801
The roles of runoff, microbial mineralization, and denitrification on the export and biogeochemical cycling of carbon and nitrogen in desert soils are not understood. Two opposing hillslopes (north vs. south-facing) in the Sevilleta National Wildlife Refuge (central New Mexico) were investigated to illustrate the importance of hillslope aspect. Additionally, the effects of hillslope elevation and soil depth were also investigated. Samples were collected at four elevations and analyzed for organic carbon and nitrogen, nitrate, ammonium, carbon and nitrogen biomass, respiration, and denitrification activity. Our results indicate that the wetter north-facing hillslope has more organic nutrients than the drier south-facing slope. Additionally, our results indicate that Juniper plant litter is an important source of these nutirents to the ecosystem. Finally, the results indicate that hillslope hydrology has an effect on the amount and rates of biogeochemical cycling of carbon and nitrogen.
 

Undergraduate Research Poster Session: Environmental Chemistry
2:00 PM-4:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008