This IAN newsletter explores the assessment of nutrient sources using stable isotope signatures of various marine organisms. This technique was developed in Moreton Bay, Australia for mapping sewage plumes, and was also used to determine the extent of aquaculture effluent (shrimp ponds) and to distinguish agricultural runoff (sugar cane) from other sources. The stable isotope ratio of nitrogen in organisms can be used to determine the influence of different nitrogen sources.

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This newsletter is a summary of the history, mission and accomplishments of the University of Maryland Center for Environmental Science (UMCES). This summary has been prepared to provide a sense of where we have come from, what we are doing and where we are going. It also serves to identify the collaborative role UMCES plays within the University System and the State of Maryland.

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A module of dynamic parameterization is added into the HSPF watershed software for simulation of dissolved inorganic nitrogen (DIN) export from forest associated with gypsy moth defoliation. It simulates a changing ecosystem following the breakout of defoliation, such as increasing mineralization and nitrification rates and soil temperature, and decreasing interception of precipitation, plant nitrogen uptake rate and evapotranspiration.

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Coral bleaching events have become more frequent and widespread, largely due to elevated sea surface temperatures. Global climate change could lead to increased variability of sea surface temperatures, through influences on climate systems, e.g. El Nino Southern Oscillation (ENSO). Field observations in 1999, following a strong ENSO, revealed that corals bleached in winter after unusually cold weather.

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Multiple Antibiotic Resistance ( MAR) analysis and regression modeling techniques were used to identify surface water areas impacted by fecal pollution from human sources, and to determine the effects of land use on fecal pollution in Murrells Inlet, a small, urbanized, high-salinity estuary located between Myrtle Beach and Georgetown, South Carolina. MAR analysis was performed to identify areas in the estuary that are impacted by human-source fecal pollution.

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This poster presents data from the lagoons along the Caribbean coast of the Yucatan Peninsula, Mexico, a region undergoing appreciable growth. The region is characterized by karst limestone without appreciable surface drainage or rivers. However, there are various submarine springs and fissures that deliver runoff to coastal waters. The tropical seagrass Thalassia testudinum was sampled near the developed regions of Cancun as well as in the Puerto Morelos lagoon to the south.

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This is the eighth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment. It details the likely impacts of climate change over the next century on U.S. coastal and marine ecosystems, including estuaries, coral reefs, and the open ocean. Coordinator: Dr Victor Kennedy … • Temperature changes in coastal and marine ecosystems will influence organism metabolism and alter ecological processes such as productivity and species interactions.

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This science newsletter focuses on the role of the Integration and Application Network (IAN) in achieving healthy Chesapeake waterways. This is the first in a series of IAN newsletters on topical issues and is directed towards the scientific and technical audience. This newsletter identifies IAN's vision for Healthy Chesapeake Waterways and includes an overview of environmental problem solving, through transfer of data into information into knowledge and ultimately into problem solving.

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Direct comparisons between photosynthetic O-2 evolution rate and electron transport rate (ETR) were made in situ over 24 h using the benthic macroalga Ulva lactuca (Chlorophyta), growing and measured at a depth of 1.8 m, where the midday irradiance rose to 400-600 mumol photons m(-2) s(-1). O-2 exchange was measured with a 5-chamber data-logging apparatus and ETR with a submersible pulse amplitude modulated (PAM) fluorometer (Diving-PAM).

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With increasing human pressures on coastal ecosystems, there is a need to develop better approaches to assess and monitor anthropogenic influences in these systems. The aims of this thesis were to a) develop indicators that describe and predict nutrient input effects, b) synthesise and interpret these indicators in assessment programs, and c) provide cost-effective methods for use in regular monitoring programs.

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