HR: 0800h
AN: H11C-0682    [Abstracts]
TI: Long-Term Springflow Reconstructions Based On Instrumental And Tree Ring Climate Records In The Missouri Ozarks
AU: Muzika, R
EM: MuzikaR@missouri.edu
AF: University of Missouri - Columbia, 203 ABNR Building, Columbia, MO 65211, United States
AU: * Hubbart, J A
EM: HubbartJ@missouri.edu
AF: University of Missouri - Columbia, 203-Q ABNR Building, Columbia, MO 65211, United States
AU: Guyette, R
EM: GuyetteR@Missouri.edu
AF: University of Missouri - Columbia, 203 ABNR Building, Columbia, MO 65211, United States
AU: Stambaugh, M
EM: StambaughM@Missouri.edu
AF: University of Missouri - Columbia, 203 ABNR Building, Columbia, MO 65211, United States
AB: To manage fresh water sustainably it is important to understand the variability of streamflow over time. Instrumental and gauged records are usually less than 50 years long and are unlikely to capture the full range of variability. Tree-ring reconstructions of streamflow are known to provide a valuable indices for past hydroclimatic trends. However, little is known of peak and low-flow attenuation of flow in karst systems, and less is known about the use of tree rings to reconstruct long-term changes in karst features such as springs. Conceptually, since underground spring (karst) systems may attenuate annual peak, high, and low flows normally shown in surface flow, springs may serve as a better proxy for flow and response time (i.e. lag time) between hydroclimatic conditions and annual tree growth. Additionally, the flows of large springs are directly affected by climate on longer time scales. This work developed spring flow reconstructions using five long-lived tree species including white oak, post oak, shortleaf pine, eastern redcedar and bur oak. Tree ring chronologies were compared to long term annual water yield records from the Current River and Big Spring near Van Buren, Missouri for the time period of 1922 through 2002 based on annual average daily flow in cubic meters per second. Average annual flow during this time period was over 56 and 12 cubic meters per second for the Current River and Big Spring respectively. Annual peak and low flow periods were substantially attenuated in the Big Spring system by approximately 20 % relative to the surface flow system of the Current River. Analysis of Variance indicated a close relationship between river flow and spring flow (R² = 0.86). Coefficients of determination for tree ring correlations to stream flow were < 0.50 for all preliminary analyses. Continued analyses including smaller stream and spring data sets will be compared to annual tree ring increment. Different classes of springs based on their elevation, stratigraphy, flow rates, and other karst features will be modeled with both instrumental and tree ring climate data. The long-term (> 5 years) climatic response and modeling of spring flows will result in the improved ability to differentiate between climate affects and land use changes in karst systems thereby better equipping land-use managers to make sound decisions facing future population, land use, and climate change scenarios.
DE: 1816 Estimation and forecasting
DE: 1830 Groundwater/surface water interaction
DE: 1832 Groundwater transport
DE: 1860 Streamflow
DE: 1894 Instruments and techniques: modeling
SC: Hydrology [H]
MN: 2007 Fall Meeting