The Comparative Roles Of Suspension Feeders In Ecosystems

Animals are a major link between the water column (pelagic) and the bottom (benthic) habitats in most shallow systems. This coupling is dominated by active processes such as suspension-feeding in which the organism actively uses energy to pump water that is then filtered to remove suspended particles that are consumed while undigested remains are deposited on the bottom. As a result of this feeding on and metabolism of particles, the animals excrete dissolved inorganic and organic waste back into the water column, and thus, become major components in the cycling and feedback of essential elements. With relatively high weight specific filtration rates of 1— 10 liters/hour/gram dry tissue and a propensity to form large aggregated populations (beds, reefs, schools and swarms), these organisms can play an important role in regulating water column processes Although estuarine bivalve molluscs such as oysters and mussels dominate the suspension-feeder literature, other groups including plankton and nekton that are found in estuarine as well as other aquatic systems are also potentially important removers of suspended particles. Thus, a significant part of the NATO Advanced Research Workshop focused on suspension-feeders as controllers of plankton abundance, biomass and diversity, system metabolism, nutrient cycling and scale dependency. Systems dominated by suspension-feeders are typically impacted by human activities including recreation, aquaculture, human and industrial pollution, and bilge water from shipping. Suspension-feeders are often impacted by fisheries and over-exploitation. These impacts commonly result in changes in ecosystem structure either through the food chain concentration of harmful substances or diseases, the introduction of alien species of suspension-feeders, or the instability of suspension-feeders systems through species displacement or phase shifts in the dominance between different suspension-feeding components such as nekton or zooplankton. These issues were addressed near the close of the workshop along with conclusions and syntheses developed by the working groups.

The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics

U.S. mariculture production of bivalve molluscs-those cultivated in the marine environment-has roughly doubled over the last 25 years. Although mariculture operations may expand the production of seafood without additional exploitation of wild populations, they still depend upon and affect natural ecosystems and ecosystem services. Every additional animal has an incremental effect arising from food extraction and waste excretion. Increasing domestic seafood production in the United States in an environmentally and socially responsible way will likely require the use of policy tools, such as best management practices (BMPs) and performance standards. BMPs represent one approach to protecting against undesirable consequences of mariculture. An alternative approach to voluntary or mandatory BMPs is the establishment of performance standards for mariculture. Variability in environmental conditions makes it difficult to develop BMPs that are sufficiently flexible and adaptable to protect ecosystem integrity across a broad range of locations and conditions. An alternative that measures performance in sustaining key indicators of ecosystem state and function may be more effective. Because BMPs address mariculture methods rather than monitoring actual ecosystem responses, they do not guarantee that detrimental ecosystem impacts will be controlled or that unacceptable impact will be avoided. Ecosystem Concepts for Sustainable Bivalve Mariculture finds that while performance standards can be applied for some broad ecosystem indicators, BMPs may be more appropriate for addressing parameters that change from site to site, such as the species being cultured, different culture methods, and various environmental conditions. This book takes an in-depth look at the environmental, social, and economic issues to present recommendations for sustainable bivalve mariculture.

Shellfish Aquaculture and the Environment focuses primarily on the issues surrounding environmental sustainability of shellfish aquaculture. The chapters in this book provide readers with the most current data available on topics such as resource enhancement and habitat restoration. Shellfish Aquaculture and the Environment is also an invaluable resource for those looking to develop and implement environmental best management practices. Edited one of the world's leading shellfish researchers and with contributions from around the world, Shellfish Aquaculture and the Environment is the definitive source of information for this increasingly important topic. View the Executive Summary here: http://seagrant.uconn.edu/publications/aquaculture/execsumm.pdf

Sedimentary coasts with their unique forms of life and productive ecosystems are one of the most threatened parts of the biosphere. This volume analyzes and compares ecological structures and processes at sandy beaches, tidal mudflats and in shallow coastal waters all around the world. Analyses of local processes are paired with comparisons between distant shores, across latitudinal gradients or between separate biogeographic provinces. Emphasis is given to suspension feeders in coastal mud and sand, to biogenic stabilizations and disturbances in coastal sediments, to seagrass beds and faunal assemblages across latitudes and oceans, to recovery dynamics in benthic communities, shorebird predation, and to experimental approaches to the biota of sedimentary shores.