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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Mesozooplankton growth rates were estimated for the Hawaiian (HOT) and Bermuda (BATS) ocean time-series stations using the empirical model of Hirst and Lampitt (Marine Biology 132 (1998) 247), which predicts copepod growth rate from temperature and body size.

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Zooplankton biomass and rates of ingestion, egestion and production in the equatorial Pacific Ocean along 140degreesW and 180degrees exhibit maximum values in the High-Nutrient Low-Chlorophyll (HNLC) zone associated with equatorial upwelling (5degreesS-5degreesN) as compared to the more oligotrophic regions to the north and south.

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Understanding the ecological role of benthic microalgae, a highly productive component of coral reef ecosystems, requires information on their spatial distribution. The spatial extent of benthic microalgae on Heron Reef (southern Great Barrier Reef, Australia) was mapped using data from the Landsat 5 Thematic Mapper sensor. integrated with field measurements of sediment chlorophyll concentration and reflectance. Field-measured sediment chlorophyll concentrations.

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Seagrass meadows are considered important for sediment trapping and sediment stabilisation. Deposition of fine sediments and associated adsorbed nutrients is considered an important part of the chemical and biological processes attributed to seagrass communities. This paradigm was based on work in temperate regions on Zostera marina and in tropical regions on Thalassia testudinum, two species that maintain relatively high biomass, stable meadows.

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Current shrimp pond management practices generally result in elevated concentrations of nutrients, suspended solids, bacteria and phytoplankton compared with the influent water. Concerns about adverse environmental impacts caused by discharging pond effluent directly into adjacent waterways have prompted the search for cost-effective methods of effluent treatment.

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Marine Pollution in the United States: Significant Accomplishments, Future Challenges has been prepared by UMCES' faculty experts for use by the Pew Oceans Commission in evaluating national oceans policy regarding environmental quality and marine resources. The Pew Oceans Commission is an independent group of distinguished Americans conducting a national dialogue on the policies needed to restore and protect living marine resources in U.S. waters.

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Despite evidence linking shrimp farming to several cases of environmental degradation, there remains a lack of ecologically meaningful information about the impacts of effluent on receiving waters. The aim of this study was to determine the biological impact of shrimp farm effluent, and to compare and distinguish its impacts from treated sewage effluent.

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This book was the third in a series of publications in support of the Healthy Waterways campaign in Southeast Queensland, Australia. It provides a guide for citizens to view various features of the waterways from specified vantage points. Grounded in the scientific understanding developed for the region, this book is an invitation to 'see it for yourself'. The book includes maps, conceptual diagrams, photos and 'catchment comments' from community leaders.

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