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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The human ecological footprint now extends to the entire globe, and human impacts are the dominant feature of many ecosystems, resulting in our current era being coined the 'anthropocene'. This is particularly apparent in coastal ecosystems as human populations are increasing rapidly in coastal cities and the ecosystem services in these areas are rapidly being compromised.

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In January 2003, the US Environmental Protection Agency sponsored a "roundtable discussion" to develop a consensus on the relationship between eutrophication and harmful algal blooms (HABs), specifically targeting those relationships for which management actions may be appropriate. Academic, federal, and state agency representatives were in attendance. The following seven statements were unanimously adopted by attendees based on review and analysis of current as well as pertinent previous data:

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Groundwater resources are being overexploited in arid and semi-arid environments globally, which necessitates a deeper understanding of the roles that groundwater plays in earth system processes. Of particular importance is the elucidation of groundwater's effect on the generation of atmospheric dust.

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