Awareness of antibiotics in wastewaters and aquatic ecosystems is growing as investigations into alternate pollutants increase and analytical techniques for detecting these chemicals improve. The presence of three antibiotics (ciproffoxacin, norfloxacin and cephalexin) was evaluated in both sewage effluent and environmental waters downstream from a sewage discharge.

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Studies in aquatic systems have shown that habitat complexity may provide refuge or reduce the number of encounters prey have with actively searching predators. For ambush predators, habitat complexity may enhance or have no effect on predation rates because it conceals predators, reduces prey detection by predators, or visually impairs both predators and prey.

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This book was the fourth in a series of publications in support of the Heathy Waterways campaign in Southeast Queensland, Australia. It synthesizes the scientific investigations focused on the catchments and waterways of the Southeast Queensland region. Chapters on the setting, habitats, sediments, nutrients, monitoring, modeling, harmful algal blooms integrate the various scientific studies occurring in the region.

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The east coast of the Yucatan Peninsula, Mexico, consists of highly permeable limestone, such that surface flow and rivers are absent in this region. Extensive underground cave systems connect sink holes (cenotes) to submarine springs (ojos de aqua), which vent into the seagrass meadows of the adjacent oligotrophic coastal lagoons.

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The Bocas del Toro archipelago in the Caribbean sea on the northwest coast of Panama has high annual rainfall (> 3000 mm) and a mountainous watershed, resulting in high inflow of fresh water. The two main lagoons have different geologic structure and different inputs; while Bahia Almirante has carbonate sediment and a relatively small watershed, Laguna de Chiriqui has predominantly siliclastic sediment and a very large watershed.

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This is the first in a series of newsletters to be produced by the Monitoring and Analysis Subcommittee (MASC). MASC coordinates and supports the monitoring activities of the Chesapeake Bay Program (CBP). Newsletters produced by MASC will summarize current and significant issues relating to the health of Chesapeake Bay ecosystems, those factors that affect the health of the Bay, and the restoration effort.

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The often-rapid deposition of phytoplankton to sediments at the end of the spring phytoplankton bloom is an important component of benthic-pelagic coupling in temperate and high latitude estuaries and other aquatic systems. However, quantifying the flux is difficult, particularly in spatially heterogeneous environments.

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Tissue samples of liver and blubber were salvaged from fifty-three dugong (Dugong dugon) carcasses stranded along the Queensland coast between 1996 and 2000. Liver tissue was analysed for a range of heavy metals and blubber samples were analysed for organochlorine compounds. Metal concentrations were similar in male and female animals and were generally highest in mature animals.

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As part of the program monitoring the ecosystem health of Moreton Bay, Queensland, Australia, we developed a means for assessing ecosystem health that allows quantitative evaluation and spatial representations of the assessments. The management objectives for achieving ecosystem health were grouped into ecosystem objectives, water quality objectives, and human health objectives.

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We conducted high-resolution, underway sampling in April, July, and October for 6 yr (1995-2000) in the large estuary, Chesapeake Bay. This period included climatological extremes in freshwater inputs that strongly influenced both the overall stocks and spatial distribution of phytoplankton and zooplankton. Higher biomass of both phytoplankton and zooplankton occurred in springs, when freshwater input into Chesapeake Bay was above the average discharge.

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