HR: 0800h
AN: H51D-1165 [Abstracts]
TI: Ecohydraulics and Estuarine Wetland Rehabilitation
AU: * Rodriguez, J F
EM: jose.rodriguez@newcastle.edu.au
AF: School of Engineering
University of Newcastle, University Drive, Callaghan, NSW 2308
Australia
AU: Howe, A
EM: alice.howe@studentmail.newcastle.edu.au
AF: School of Engineering
University of Newcastle, University Drive, Callaghan, NSW 2308
Australia
AU: Saintilan, N
EM: n.saintilan@mackillop.acu.edu.au
AF: Centre for Environmental Restoration and Stewardship
Australian Catholic University, P.O. Box 968, North Sydney, NSW 2059
Australia
AU: Spencer, J
EM: jaspen003@student.mackillop.acu.edu.au
AF: Centre for Environmental Restoration and Stewardship
Australian Catholic University, P.O. Box 968, North Sydney, NSW 2059
Australia
AB:
The hydraulics or water flow in wetlands is known to be a key factor influencing ecosystem development in estuarine wetland
environments. The relationship is indirect, with the hydraulics of wetlands influencing a host of factors including soil
salinity, waterlogging, sediment transport, sediment chemistry, vegetation dispersal and growth and nutrient availability and
cycling. The relationship is also not one way, with the hydraulics of wetlands being influenced by plant and animal
activity. Understanding these complex interactions is fundamental for the adequate management of estuarine wetlands.
Listed as a Wetland of International Importance under the 1971 Ramsar Convention, the Hunter River estuary is regarded as the
most significant site for migratory shorebirds in New South Wales, Australia. Over the past 20 years, the number of
migratory shorebirds in the estuary has sharply declined from 8,000 to 4,000 approx. Alteration of bird habitat is believed
to be one of the reasons for this alarming trend.
In 2004 we started a three-year program to investigate the links between hydraulics, sediment, benthic invertebrates,
vegetation and migratory shorebird habitat in the estuary. During the first year we have focused on a highly disturbed part
of the Hunter estuary wetlands located on Ash Island. The area is one of the major roosting sites in the estuary and is
characterized by a complex hydraulic regime due to a restricted tidal interchange with the Hunter River and the presence of
infrastructure for the maintenance of power lines (i.e., roads, bridges, culverts). Salt marshes, mudflat and mangroves are
the dominant vegetation types. The monitoring program includes measurements of water levels, salinity, discharge, velocity,
turbulence, sediment transport and deposition, plant species and density, soil composition and benthic invertebrates
coordinated with observations of bird habitat utilization on a number of locations throughout the wetland and for different
flow conditions. We present a preliminary analysis of the data aimed at the hydrodynamic and geomorphologic characterization
of the different vegetation zones and the resulting habitat properties.
DE: 4815 Ecosystems, structure and dynamics
DE: 1803 Anthropogenic effects
DE: 1824 Geomorphology (1625)
DE: 1851 Plant ecology
DE: 1890 Wetlands
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting