HR: 17:35h
AN: H44A-06    [Abstracts]
TI: An Integrated Model for Evaluating Hydrology, Hydrodynamics, Water Quality and Ecology in a Coastal Desert Wetland
AU: * Huckelbridge, K H
EM: katehuck@ce.berkeley.edu
AF: University of California, Berkeley, Department of Civil and Environmental Engineering, 760 Davis Hall, Berkeley, CA 94720, United States
AU: Stacey, M T
EM: mstacey@berkeley.edu
AF: University of California, Berkeley, Department of Civil and Environmental Engineering, 760 Davis Hall, Berkeley, CA 94720, United States
AU: Glenn, E P
EM: eglenn@Ag.arizona.edu
AF: The University of Arizona, Environmental Research Laboratory, 2601 East Airport Drive, Tucson, AZ 85706, United States
AU: Dracup, J A
EM: dracup@ce.berkeley.edu
AF: University of California, Berkeley, Department of Civil and Environmental Engineering, 760 Davis Hall, Berkeley, CA 94720, United States
AB: An integrated model describing hydrology, hydrodynamics, salt dynamics and vegetation was developed to predict the evolution of the Cienega de Santa Clara ("Cienega"), a non-tidal wetland located in the Colorado River Delta. The Cienega was created in 1977 when water intended for treatment at the Yuma Desalting Plant in Arizona was bypassed to a salt flat in the Delta. The continued delivery of this water is uncertain and thus, this model was developed to predict the effects of changes in the quantity and quality of inflow to the wetland over seasonal and annual timescales. The model is divided into four modules that run in sequence for each timestep, in which the results from one module are used to produce results in successive modules. The four modules are: (1) evapotranspiration, (2) water balance, (3) mixing/salt balance, and (4) vegetation response. Over the calibration period, 1993-2002, modeled results of wetland surface area, the fraction of the wetland covered in vegetation and salinity concentrations compare well to actual data. The model was used to run nine hypothetical scenarios, representing the range of inflow quantity and quality to the Cienega that could occur if the source of the inflow is altered, including the possible re-opening of the Yuma Desalting plant. Model results show that the Cienega ecosystem is more sensitive to changes in salinity than to changes in flow. However, in almost all cases, an increase in salinity and/or a decrease in flow would cause a significant decrease in wetland size and vegetation cover, compromising a large portion of the habitat currently available to wildlife at the Cienega.
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0497 Wetlands (1890)
DE: 1813 Eco-hydrology
DE: 1847 Modeling
SC: Hydrology [H]
MN: 2007 Joint Assembly