HR: 1340h
AN: B43B-0284    [Abstracts]
TI: The Ecogeomorphology of Salt Pools of the Webhannet Estuary, Wells, Maine, USA
AU: * Wilson, K R
EM: kristin.wilson@umit.maine.edu
AF: School of Marine Sciences, University of Maine, Orono, ME 04469 United States
AU: Kelley, J T
EM: jtkelley@maine.edu
AF: School of Marine Sciences, University of Maine, Orono, ME 04469 United States
AB: Salt pools are shallow, muddy depressions in salt marshes that remain flooded throughout the entire tidal cycle. They are common landforms of this ecosystem, but little is known for certain about their formation and persistence through time. Understanding the ontogeny of salt pools is critical, as it has been suggested that they may serve as important habitat for some birds and fish, and as indicators of ultimate marsh break-up and wetland loss. Hypotheses regarding pool initiation have suggested that pools are primary features of marshes, while others have suggested that pools form through secondary mechanisms such as isolated vegetative die-off or ice-plucking. Still others have suggested that pools may be associated with tidal creek abandonment. This study combines field observations, geologic coring, and analyses of a time-series of aerial photographs through geographic information systems (GIS), to quantify the recent history of pools of the Webhannet Estuary, Wells, ME, USA. Six transects sampled 119 pools during Summers 2004/2005. Adjacent percent vegetative cover (3, 1m2 plots/pool), bank classification (graded, mostly graded, mostly steep, steep), pool shape (circular, figure eight, irregular, sinuous) and a handheld GPS point were recorded. GPS data points were imported into a GIS platform to determine spatial trends. Examination of the spatial distribution suggests that pools are not randomly distributed across the marsh surface, but rather exhibit strong spatial patterns based on the pool characteristics described. Preliminary analyses of aerial photographs comparing the marsh surface in 1953 to 2003, suggest pools exhibit different developmental sequences over time (some grow, some shrink, some remain the same in area and shape). Dutch cores taken during Summer 2005 reveal a distinct pool signature and suggest that some pools may be of a more ephemeral nature than previously described and support the hypothesis that pools form through secondary mechanisms. New understanding of the development of salt pools may have practical management implications.
DE: 0442 Estuarine and nearshore processes (4235)
SC: Biogeosciences [B]
MN: Fall Meeting 2005