Effects of nutrient enrichment in the nation's estuaries: A decade of change

Bricker SB, Longstaff BJ, Dennison WC, Jones AB, Boicourt KE, Wicks EC, and Woerner J ·
2008

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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Trophic Transfers from Seagrass Meadows Subsidize Diverse Marine and Terrestrial Consumers (Page 1)

Trophic Transfers from Seagrass Meadows Subsidize Diverse Marine and Terrestrial Consumers

Heck KL, Carruthers TJB, Duarte CM, Hughes AR, Kendrick G, Orth RJ, and Williams SW ·
2008

In many coastal locations, seagrass meadows are part of a greater seascape that includes both marine and terrestrial elements, each linked to the other via the foraging patterns of consumers (both predators and herbivores), and the passive drift of seagrass propagules, leaves, roots and rhizomes, and seagrass-associated macroalgal detritus. With seagrasses declining in many regions, the linkages between seagrass meadows and other habitats are being altered and diminished.


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Using the aquatic macrophyte Vallisneria americana (wild celery) as a nutrient bioindicator (Page 1)

Using the aquatic macrophyte Vallisneria americana (wild celery) as a nutrient bioindicator

Benson ER, O'Neil JM, and Dennison WC ·
2008

Human sewage and septic waste are significant sources of nutrient loading to many aquatic ecosystems. Ecologically relevant nitrogen sources can be traced by analyzing nitrogen stable isotope ratios (δ15N signatures) in aquatic plants. Elevated δ15N signatures can suggest increased uptake of nitrogen derived from human and/or animal waste. In the current study, Vallisneria americana, a freshwater angiosperm, was collected from several locations in Upper Saranac Lake, NY, USA.


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Groundwater influences on atmospheric dust generation in deserts

Elmore AJ, Kaste JM, Okin GS, and Fantle MS ·
2008

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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The charisma of coastal ecosystems: addressing the imbalance (Page 1)

The charisma of coastal ecosystems: addressing the imbalance

Duarte CM, Dennison WC, Orth RJ, and Carruthers TJB ·
2008

Coastal ecosystems including coral reefs, mangrove forests, seagrass meadows, and salt marshes are being lost at alarming rates, and increased scientific understanding of causes has failed to stem these losses. Coastal habitats receive contrasting research effort, with 60% of all of the published research carried out on coral reefs, compared to 11–14% of the records for each of salt marshes, mangrove forests, and seagrass meadows.


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A descriptive analysis of temporal and spatial patterns of variability in Puget Sound oceanographic properties

Moore SK, Mantua NJ, Newton JA, Kawase M, Warner MJ, and Kellogg JP ·
2008

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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Environmental problem solving in coastal ecosystems: A paradigm shift to sustainability (Page 1)

Environmental problem solving in coastal ecosystems: A paradigm shift to sustainability

Dennison WC ·
2008

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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Local and large-scale climate forcing of Puget Sound oceanographic properties on seasonal to interdecadal timescales

Moore SK, Mantua NJ, Kellogg JP, and Newton JA ·
2008

The influence of climate on Puget Sound oceanographic properties is investigated on seasonal to interannual timescales using continuous profile data at 16 stations from 1993 to 2002 and records of sea surface temperature (SST) and sea surface salinity (SSS) from 1951 to 2002. Principal components analyses of profile data identify indices representing 42%, 58%, and 56% of the total variability at depth-station combinations for temperature, salinity, and density, respectively…


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Eutrophication and harmful algal blooms: A scientific consensus (Page 1)

Eutrophication and harmful algal blooms: A scientific consensus

Heisler J, Glibert PM, Burkholder JM, Anderson DM, Cochlan W, Dennison WC, Dortch Q, Gobler CJ, Heil CA, Humphries E, Lewitus A, Magnien R, Marshall HG, Sellner K, Stockwell DA, Stoecker DK, and Suddleson M ·
2008

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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Detecting open vegetation in a forested landscape: pollen and remote sensing data from New England, USA (Page 1)

Detecting open vegetation in a forested landscape: pollen and remote sensing data from New England, USA

McLauchlan KK, Elmore AJ, Oswald WW, and Sugita S ·
2007

The proportional cover of forest and grassland vegetation, known as landscape openness, has been particularly difficult to reconstruct because of differences in pollen productivity and transport between the two vegetation types. To begin to calibrate landscape openness in eastern North America, we collected 2 1 samples of surface sediments front small ponds (less than 60 ha) in the Upper Connecticut River Valley of New England, USA.


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