Publications

Over the past century, seagrass habitats from the bays of Texas to the gulf shores of Florida have decreased. Seagrass beds, which are highly dependent on water quality and clarity for survival, are home to a multitude of aquatic plants and animals and a source of economic activity through commercial and recreational fishing and ecotourism. The U.S. Environmental Protection Agency’s Gulf...

Aim The long-term stability of coastal ecosystems such as mangroves and salt marshes depends upon the maintenance of soil elevations within the intertidal habitat as sea level changes. We examined the rates and processes of peat formation by mangroves of the Caribbean Region to better understand biological controls on habitat stability. Location Mangrove-dominated islands on the...

Felsenthal Navigation Pool (?the pool?) at Felsenthal National Wildlife Refuge near Crossett, Ark., was continuously flooded to a baseline elevation of 19.8 m (65.0 ft) mean sea level (m.s.l.) from late fall 1985, when the final in a series of locks and dams was constructed, until the summer of 1995. Water level within the pool was reduced by 0.3 m (1.0 ft) beginning July 5, 1995...

In 2001, the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey began a series of studies on the transport of anthropogenic and natural contaminants (TANC) to public-supply wells. The main goal of the TANC program was to better understand the source, transport, and receptor factors that control contaminant movement to public-supply wells in representative...

Hurricane Katrina caused extreme changes to the barrier islands of the central Gulf of Mexico coast. Dauphin Island, Ala., migrated landward and stranded the remains of its oceanfront row homes in the sea. Chandeleur Islands, La., were completely stripped of their sand, leaving only marshy outcrops in the storm's wake.

The occurrence of hurricane landfalls on the United States may be related to alternating intervals of persistent above-average and below-average surface temperature of the North Atlantic Ocean. The cycle of temperature variations, known as the Atlantic Multidecadal Oscillation (AMO), has been identified by study of records based on thermometer readings that go back to the late 1800s...

In this study, time-series stable isotope results (δ13C and δ15N) from three deep-water Leiopathes glaberrima(Esper, 1788) specimens Collected off the southeastern Coast of the United States of America and one specimen from the Gulf of Mexico are presented. The specimens were Collected live in 2004 and are estimated to be 200–500 yrs old based on 210Pb measurements and band Counts. The...

Wetlands of the Mississippi River deltaic plain in southeast Louisiana have been hydrologically isolated from the Mississippi River by containment levees for nearly a century. The ensuing lack of fluvial sediment inputs, combined with natural submergence processes, has contributed to high coastal land loss rates. Controlled river diversions have since been constructed to reconnect the...

The frequency of hurricane landfall in a given coastal stretch may play a more important role in the ecology of coastal forests than previously thought because of direct and indirect impacts of fallen trees and the introduction of salt water that lingers long after the storm passes. Findings show that surge events can inundate interior freshwater forests many miles from the coast and...

Satellite images from multiple sensors and dates were analyzed to measure the extent of flooding caused by Hurricane Katrina in the New Orleans, La., area. The flood polygons were combined with a high-resolution digital elevation model to estimate water depths and volumes in designated areas. The multiple satellite acquisitions enabled monitoring of the floodwater volume and extent...

Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1??? for ?? 13C and 2-3??? for ?? 15N, among the invertebrates...

Hurricanes Katrina and Rita pushed salt water from the Gulf of Mexico well inland into freshwater marsh communities in coastal Louisiana. This paper describes the spatial extent of saltwater intrusion and provides an initial assessment of impacts (salt stress) to coastal marsh vegetation communities.