The northern Gulf of Mexico (NGOMEX) was surveyed to examine the broad-scale spatial patterns and inter-relationships between hypoxia (< 2 mg L-1 dissolved oxygen) and zooplankton biovolume. We used an undulating towed body equipped with sensors for conductivity, temperature, depth, oxygen, fluorescence, and an optical plankton counter to sample water column structure, oxygen, and zooplankton at high spatial resolution (1 m-vertical; 0.25-1 km-horizontal).

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The timing of spring leaf development, trajectories of summer leaf area, and the timing of autumn senescence have profound impacts to the water, carbon, and energy balance of ecosystems, and are likely influenced by global climate change. Limited field-based and remote-sensing observations have suggested complex spatial patterns related to geographic features that influence climate.

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The purpose of this study was to elaborate on the role of coastal megacities in environmental degradation and their contribution to global climate change. Although only less than 4 percent of the total world's population resides in coastal megacities, their impact on environment is significant due to their rapid development, high population densities and high consumption rate of their residents.

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Development of Environmentally Superior Technologies for swine waste management has focused on extraction of products with relatively low unit values. Analyses of the bacterial composition of swine waste lagoon samples confirmed the presence of several purple non-sulfur bacteria (PNSB) species known to produce a variety of carotenoids. We examined a carotenoid naturally abundant in North Carolina swine waste lagoons dominated by PNSB.

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Human intervention has resulted in a number of global and river syndromes that are mirrored by coastal syndromes caused by erosion, subsidence, salinization of aquifers, urbanization, eutrophication, invasive species and over exploitation of natural resources. These problems are now global, with few coastal zones remaining unaffected and pristine. However, the problems are particularly severe at "hotspots" in the coastal zone.

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Future climates are forecast to include greater precipitation variability and more frequent heat waves, but the degree to which the timing of climate variability impacts ecosystems is uncertain. In a temperate, humid grassland, we examined the seasonal impacts of climate variability on 27 y of grass productivity. Drought and high-intensity precipitation reduced grass productivity only during a 110-d period, whereas high temperatures reduced productivity only during 25 d in July.

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Beryllium-7 is a potentially powerful tracer of atmospheric deposition and recent sediment transport, but the quantity and distribution of Be-7 on arid landscapes have not been described. We measured Be-7 in soil, vegetation, and dust in Owens Valley, California, and describe its distribution in aridisols and mollisols to evaluate its potential as a sediment tracer in desert environments.

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Improving watershed nutrient budgets, ecosystem models, and our understanding of the impact of land-use management on ecosystem functioning depends on the development of remote sensing methods that can predict aspects of the nitrogen (N) cycle. This is particularly true for temperate managed grasslands, which constitute a large portion of agricultural land and, at times, export a significant amount of N to aquatic systems and the atmosphere.

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The Integrated Ocean Observing System (100S (R)) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality.

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During systematic repeat hydrography cruises to the Endeavour segment of the Juan de Fuca Ridge in the summers of 2004, 2005, and 2006, we encountered a transient increase in the water column heat content above the Salty Dawg hydrothermal field. First observed in July 2005 and mapped in greater detail in August 2005, this feature was not a typical event or megaplume since potential temperature anomalies were continuously elevated from the plume top to the seafloor.

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