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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Management of coastal systems is becoming increasingly important, however understanding the process of effective management often remains elusive. This chapter contrasts examples of environmental problems and associated management in Moreton Bay, Australia, and Chesapeake Bay, USA. Targeted research in Moreton Bay identified specific issues which led to changed practices, while intense management and research in Chesapeake Bay has been unable to keep pace with increasing anthropogenic stress.

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Increases in contaminants associated with urban sprawl are a particular concern in the rapidly developing coastal areas of the southeastern United States. Polycyclic aromatic hydrocarbons (PAHs) are contaminants associated with vehicle emissions and runofff from impervious surfaces. Increased vehicular traffic and more impervious surfaces lead to an increased loading of PAHs into coastal estuarine systems.

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The abundance and productivity of benthic microalgae in coral reef sediments are poorly known compared with other, more conspicuous (e.g. coral zooxanthellae, macroalgae) primary producers of coral reef habitats.

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While the remote-sensing community attempts to find measures of reef ‘‘health’’ able to be detected and mapped using satellite image data, internationally recognized field assessments are already in place to document benthic cover, among other parameters, as an indicator of coral reef status. Reef Check is one such program, designed in 1996 as a globally applicable, rapid, field-survey protocol for coral reef health monitoring by volunteer divers (Hodgson 1999).

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A time-series analysis of airborne photographs and Landsat thematic mapper (TM and ETM+) images and hydrochemical data were used to examine the effects of land-use change from 1930 to 2001 on solute inputs to Lake Calado, a floodplain lake in the central Amazon. Deforestation from slash-and-burn agricultural activities has dramatically decreased the amount of primary growth upland and flooded forests in the basin.

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Coral cays form part of the Australian Great Barrier Reef. Coral cays with high densities of seabirds are areas of extreme nitrogen (N) enrichment with deposition rates of up to 1000 kg N ha(-1) y(-1). The ways in which N sources are utilised by coral cay plants, N is distributed within the cay, and whether or not seabird-derived N moves from cay to surrounding marine environments were investigated.

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A module of dynamic parameterization is added into the HSPF watershed software for simulation of dissolved inorganic nitrogen (DIN) export from forest associated with gypsy moth defoliation. It simulates a changing ecosystem following the breakout of defoliation, such as increasing mineralization and nitrification rates and soil temperature, and decreasing interception of precipitation, plant nitrogen uptake rate and evapotranspiration.

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Coral bleaching events have become more frequent and widespread, largely due to elevated sea surface temperatures. Global climate change could lead to increased variability of sea surface temperatures, through influences on climate systems, e.g. El Nino Southern Oscillation (ENSO). Field observations in 1999, following a strong ENSO, revealed that corals bleached in winter after unusually cold weather.

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