HR: 0800h
AN: H31B-1312    [Abstracts]
TI: Quantifying the Effects of Vegetation and Water Source on Water Quality in Three Watersheds in Valles Caldera National Preserve, New Mexico.
AU: * Kostrzewski, J M
EM: jenk@hwr.arizona.edu
AF: Department of Hydrology and Water Resources, University of Arizona, 1133 E. North Campus Dr Harshbarger Bldg, PO Box 210011, Tucson, AZ 85721 United States
AU: Brooks, P D
EM: brooks@hwr.arizona.edu
AF: Department of Hydrology and Water Resources, University of Arizona, 1133 E. North Campus Dr Harshbarger Bldg, PO Box 210011, Tucson, AZ 85721 United States
AB: We assessed impacts of vegetative cover and water source on water quality in the Valles Caldera National Preserve (VCNP). Within the preserve we selected three montane watersheds due to vegetative and physical characteristics. Redondo Creek with an area of 11.7 mi² is a higher elevation (7,000 to 11,200 ft) watershed with a vegetation transition from aspen to ponderosa pine to meadow. The La Jara Creek is a bedrock confined watershed with an area of 1.5 mi², elevation range of 8,500 to 11,200 ft, and predominate vegetative cover of mixed conifer. The Jaramillo Creek is a lower elevation (8,500 to 10,500 ft) alluvial watershed with an area of 4.5 mi² which is dominated by grassland vegetation. In the spring, early summer, and late summer we preformed stream and tributary synoptic sampling combined with regular fixed point sampling. Our experimental design includes analysis of conservative solutes (F^-, Br^-, Cl^-, SO₄^2-), water isotopes, and biogeochemical nutrients to quantify water sources, age, and biological influence within each catchment. Preliminary analysis of dissolved organic carbon (DOC) data suggests an early flushing of DOC in all three catchments to a reduced concentration in the early summer months. Elevated chloride and sulfate concentrations in Redondo Creek indicate a deeper water source than La Jara Creek. This difference in water source contributes to the higher variation of DOC concentrations in La Jara Creek (x=2.33 mg/L, s.d.=1.22) and a lower variation in Redondo Creek (x=2.72 mg/L, s.d.=0.49). A continuation of conservative solute and isotopic analyses will constrain hydrologic flow paths to evaluate the effects of vegetation and water source on water quality.
DE: 1804 Catchment
DE: 1806 Chemistry of fresh water
DE: 1813 Eco-hydrology
SC: Hydrology [H]
MN: Fall Meeting 2005