For many studies of urbanization, particularly those covering broad spatial extents and thus requiring the perspective afforded by satellite remote sensing, the longest time series of impervious surface area (ISA) initiate with the availability of Landsat Thematic Mapper (TM) data in the mid 1980s.

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The relevance of the boundary concept to ecological processes has been recently questioned. Humans in the post-industrial era have created novel lateral transport fluxes that have not been sufficiently considered in watershed studies. We describe patterns of land-use change within the Potomac River basin and demonstrate how these changes have blurred traditional ecosystem boundaries by increasing the movement of people, materials, and energy into and within the basin.

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In an effort to better portray changing health conditions in Chesapeake Bay and support restoration efforts, a Bay Health Index (BHI) was developed to assess the ecological effects of nutrient and sediment loading on 15 regions of the estuary. Three water quality and three biological measures were combined to formulate the BHI.

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Ratios of nitrogen (N) isotopes in leaves could elucidate underlying patterns of N cycling across ecological gradients. To better understand global-scale patterns of N cycling, we compiled data on foliar N isotope ratios (delta N-15), foliar N concentrations, mycorrhizal type and climate for over 11 000 plants worldwide.

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This paper presents a multiple-pattern parameter identification and uncertainty analysis approach for robust water quality modeling using a neural network (NN) embedded genetic algorithm (GA). The modeling approach uses an adaptive NN-GA framework to inversely solve the governing equations in a water quality model for multiple parameter patterns. along with an alternating fitness method to maintain solution diversity.

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Seagrasses: biology, ecology and conservation, edited by Tony Larkum, Bob Orth and Carlos Duarte, and authored by 79 active seagrass researchers is the most comprehensive book about these unique flowering plants ever written. It is long, 691 pp, with an excess of 100 pages devoted to references, and it includes 26 chapters on evolution, anatomy, biology, physiology, biogeochemistry, remote sensing, grazing and predation, ecology, and management.

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The presence of 28 antibiotics in three hospital effluents, five wastewater treatment plants (WWTPs), six rivers and a drinking water storage catchment were investigated within watersheds of South-East Queensland, Australia. All antibiotics were detected at least once, with the exception of the polypeptide bacitracin which was not detected at all. Antibiotics were found in hospital effluent ranging from 0.01-14.5 [mu]g L(-1), dominated by the beta-lactam, quinolone and sulphonamide groups.

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Temporal and spatial patterns of variability in Puget Sound's oceanographic properties are determined using continuous vertical profile data from two long-term monitoring programs; monthly observations at 16 stations from 1993 to 2002, and biannual observations at 40 stations from 1998 to 2003. Climatological monthly means of temperature, salinity, and density reveal strong seasonal patterns.

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Headwater streams provide important ecosystem services, including clean drinking water, habitat for aquatic life, and rapid processing and uptake of nutrients, which can reduce delivery of nitrogen and phosphorus to downstream coastal waters. Despite their importance to ecosystem functioning, very little research has addressed the extent to which headwater streams are buried beneath the land surface during urbanization.

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An updated assessment of nutrient related impacts in US estuaries was completed in 2007. This assessment evaluates three components for each estuary: the influencing factors (e.g. land use, nutrient loads), the overall eutrophic condition (e.g. chlorophyll a, presence of nuisance/toxic algae and macroalgae, extent of dissolved oxygen problems, loss of submerged aquatic vegetation), and future outlook.

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