HR: 1330h
AN: NB33F-02    [Abstracts]
TI: Whole-stream and Sediment Nitrification of Four Streams in Grand Teton National Park and Jackson, Wyoming
AU: * Neerhof, L
EM: lisa@uwyo.edu
AF: Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071 United States
AU: Hall, R
EM: bhall@uwyo.edu
AF: Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071 United States
AB: Increasing levels of nitrate in stream and river ecosystems due to anthropogenic inputs make the need for nitrate control more apparent. Elevated streamwater nitrate concentrations can result from nitrate inputs from agricultural fertilizer application; however, nitrate can also be produced within the stream via nitrification. Estimating the relative contributions from these sources will allow managers to make more informed decisions to promote ecosystem health. Sediment and whole-stream nitrification rates were measured in four streams during the summer of 2004. The streams were located in Grand Teton National Park and Jackson, Wyoming. Nitrification rates in the sediment were estimated using the nitrapyrin assay method, and whole-stream nitrification rates were estimated using short-term NH₄Cl enrichments. The background water column nitrate concentration ranged from 4.86μg NO₃ L^-1 to 134.59μg NO₃ L^-1. Average sediment nitrification rates varied, ranging from 1.95 to 9.89 μg N m^-2 min^-1. In contrast, whole-stream nitrification (16 μg N m^-2 min^-1) may be higher than sediment nitrification. This study suggests that sediment nitrification rates are similar but less than the whole-stream nitrification rates. Variation in nitrification estimates raises questions for further investigation.
DE: 1806 Chemistry of fresh water
DE: 1845 Limnology
DE: 9901 NABS Student Award - Basic Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly