HR: 11:00h
AN: NB52D-02    [Abstracts]
TI: Spatial Heterogeneity in Water Quality across a Restored Floodplain: Implications for Fish and Those Who Care About Them
AU: Mount, J F
EM: mount@geology.ucdavis.edu
AF: Department of Geology, University of California, Davis, CA 95616 United States
AU: * Ahearn, D S
EM: dsahearn@ucdavis.edu
AF: Department of Land, Air, and Water Resources, University of California, Davis, CA 95616 United States
AU: Gallo, E L
EM: elgallo@ucdavis.edu
AF: Department of Land, Air, and Water Resources, University of California, Davis, CA 95616 United States
AU: Jeffres, C
EM: cajeffres@ucdavis.edu
AF: John Muir Institute of the Environment, University of California, Davis, CA 95616 United States
AB: High resolution spatial monitoring of floodwaters across an experimental floodplain in Central California has revealed patterns in dissolved organic carbon, chlorophyll-a, and nutrients which may have ramifications for local biota and future floodplain restorations. In 2004, seven sites across a 40 ha restored floodplain were monitored before and after 3 major floods. Additionally, in 2005, a multi-parameter sonde with GPS capabilities was used to create a high-resolution water quality map of the floodplain. Floods acted to reset, homogenize, and push productive antecedent waters across the floodplain. Productivity was greatest in shallow areas shortly after storms. As water stagnated on the floodplain deep water areas became more productive with chlorophyll-a levels reaching 17 μg l^-1. Concurrently, vegetated shallow areas released dissolved organic carbon and nutrients and became hypoxic as algae senesced. A parallel fish enclosure study revealed that fish growth was greatest in shallow areas shortly after storms. The fish enclosed in deepwater areas grew faster as shallow water habitat began to decline. Habitat heterogeneity drives water quality variability across the floodplain which in turn influences the local biota, such heterogeneity is important for healthy ecosystem function and should be an integral part of future floodplain restorations.
DE: 1845 Limnology
DE: 1871 Surface water quality
DE: 1890 Wetlands
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly