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Caryn C Vaughn - One of the best experts on this subject based on the ideXlab platform.

  • Bivalve Impacts in Freshwater and Marine Ecosystems
    Annual Review of Ecology Evolution and Systematics, 2018
    Co-Authors: Caryn C Vaughn, Timothy J. Hoellein
    Abstract:

    Bivalve molluscs are abundant in marine and freshwater ecosystems and perform important ecological functions. Bivalves have epifaunal or infaunal lifestyles but are largely filter feeders that coup...

  • the functional role of burrowing Bivalves in freshwater ecosystems
    Freshwater Biology, 2001
    Co-Authors: Caryn C Vaughn, Christine C Hakenkamp
    Abstract:

    1. Freshwater systems are losing biodiversity at a rapid rate, yet we know little about the functional role of most of this biodiversity. The ecosystem roles of freshwater burrowing Bivalves have been particularly understudied. Here we summarize what is known about the functional role of burrowing Bivalves in the orders Unionoida and Veneroida in lakes and streams globally. 2. Bivalves filter phytoplankton, bacteria and particulate organic matter from the water column. Corbicula and sphaeriids also remove organic matter from the sediment by deposit feeding, as may some unionids. Filtration rate varies with Bivalve species and size, temperature, particle size and concentration, and flow regime. 3. Bivalves affect nutrient dynamics in freshwater systems, through excretion as well as biodeposition of faeces and pseudofaeces. Excretion rates are both size and species dependent, are influenced by reproductive stage, and vary greatly with temperature and food availability. 4. Bioturbation of sediments through Bivalve movements increases sediment water and oxygen content and releases nutrients from the sediment to the water column. The physical presence of Bivalve shells creates habitat for epiphytic and epizoic organisms, and stabilizes sediment and provides refugia for benthic fauna. Biodeposition of faeces and pseudofaeces can alter the composition of benthic communities. 5. There is conflicting evidence concerning the role of resource limitation in structuring Bivalve communities. Control by Bivalves of primary production is most likely when their biomass is large relative to the water volume and where hydrologic residence time is long. Future studies should consider exactly what Bivalves feed upon, whether feeding varies seasonally and with habitat, and whether significant overlap in diet occurs. In particular, we need a clearer picture of the importance of suspension versus deposit feeding and the potential advantages and tradeoffs between these two feeding modes. 6. In North America, native burrowing Bivalves (Unionidae) are declining at a catastrophic rate. This significant loss of benthic biomass, coupled with the invasion of an exotic burrowing Bivalve (Corbicula), may result in large alterations of ecosystem processes and functions.

  • the functional role of burrowing Bivalves in freshwater ecosystems
    Freshwater Biology, 2001
    Co-Authors: Caryn C Vaughn, Christine C Hakenkamp
    Abstract:

    1. Freshwater systems are losing biodiversity at a rapid rate, yet we know little about the functional role of most of this biodiversity. The ecosystem roles of freshwater burrowing Bivalves have been particularly understudied. Here we summarize what is known about the functional role of burrowing Bivalves in the orders Unionoida and Veneroida in lakes and streams globally. 2. Bivalves filter phytoplankton, bacteria and particulate organic matter from the water column. Corbicula and sphaeriids also remove organic matter from the sediment by deposit feeding, as may some unionids. Filtration rate varies with Bivalve species and size, temperature, particle size and concentration, and flow regime. 3. Bivalves affect nutrient dynamics in freshwater systems, through excretion as well as biodeposition of faeces and pseudofaeces. Excretion rates are both size and species dependent, are influenced by reproductive stage, and vary greatly with temperature and food availability. 4. Bioturbation of sediments through Bivalve movements increases sediment water and oxygen content and releases nutrients from the sediment to the water column. The physical presence of Bivalve shells creates habitat for epiphytic and epizoic organisms, and stabilizes sediment and provides refugia for benthic fauna. Biodeposition of faeces and pseudofaeces can alter the composition of benthic communities. 5. There is conflicting evidence concerning the role of resource limitation in structuring Bivalve communities. Control by Bivalves of primary production is most likely when their biomass is large relative to the water volume and where hydrologic residence time is long. Future studies should consider exactly what Bivalves feed upon, whether feeding varies seasonally and with habitat, and whether significant overlap in diet occurs. In particular, we need a clearer picture of the importance of suspension versus deposit feeding and the potential advantages and tradeoffs between these two feeding modes. 6. In North America, native burrowing Bivalves (Unionidae) are declining at a catastrophic rate. This significant loss of benthic biomass, coupled with the invasion of an exotic burrowing Bivalve (Corbicula), may result in large alterations of ecosystem processes and functions.

Christine C Hakenkamp - One of the best experts on this subject based on the ideXlab platform.

  • the functional role of burrowing Bivalves in freshwater ecosystems
    Freshwater Biology, 2001
    Co-Authors: Caryn C Vaughn, Christine C Hakenkamp
    Abstract:

    1. Freshwater systems are losing biodiversity at a rapid rate, yet we know little about the functional role of most of this biodiversity. The ecosystem roles of freshwater burrowing Bivalves have been particularly understudied. Here we summarize what is known about the functional role of burrowing Bivalves in the orders Unionoida and Veneroida in lakes and streams globally. 2. Bivalves filter phytoplankton, bacteria and particulate organic matter from the water column. Corbicula and sphaeriids also remove organic matter from the sediment by deposit feeding, as may some unionids. Filtration rate varies with Bivalve species and size, temperature, particle size and concentration, and flow regime. 3. Bivalves affect nutrient dynamics in freshwater systems, through excretion as well as biodeposition of faeces and pseudofaeces. Excretion rates are both size and species dependent, are influenced by reproductive stage, and vary greatly with temperature and food availability. 4. Bioturbation of sediments through Bivalve movements increases sediment water and oxygen content and releases nutrients from the sediment to the water column. The physical presence of Bivalve shells creates habitat for epiphytic and epizoic organisms, and stabilizes sediment and provides refugia for benthic fauna. Biodeposition of faeces and pseudofaeces can alter the composition of benthic communities. 5. There is conflicting evidence concerning the role of resource limitation in structuring Bivalve communities. Control by Bivalves of primary production is most likely when their biomass is large relative to the water volume and where hydrologic residence time is long. Future studies should consider exactly what Bivalves feed upon, whether feeding varies seasonally and with habitat, and whether significant overlap in diet occurs. In particular, we need a clearer picture of the importance of suspension versus deposit feeding and the potential advantages and tradeoffs between these two feeding modes. 6. In North America, native burrowing Bivalves (Unionidae) are declining at a catastrophic rate. This significant loss of benthic biomass, coupled with the invasion of an exotic burrowing Bivalve (Corbicula), may result in large alterations of ecosystem processes and functions.

  • the functional role of burrowing Bivalves in freshwater ecosystems
    Freshwater Biology, 2001
    Co-Authors: Caryn C Vaughn, Christine C Hakenkamp
    Abstract:

    1. Freshwater systems are losing biodiversity at a rapid rate, yet we know little about the functional role of most of this biodiversity. The ecosystem roles of freshwater burrowing Bivalves have been particularly understudied. Here we summarize what is known about the functional role of burrowing Bivalves in the orders Unionoida and Veneroida in lakes and streams globally. 2. Bivalves filter phytoplankton, bacteria and particulate organic matter from the water column. Corbicula and sphaeriids also remove organic matter from the sediment by deposit feeding, as may some unionids. Filtration rate varies with Bivalve species and size, temperature, particle size and concentration, and flow regime. 3. Bivalves affect nutrient dynamics in freshwater systems, through excretion as well as biodeposition of faeces and pseudofaeces. Excretion rates are both size and species dependent, are influenced by reproductive stage, and vary greatly with temperature and food availability. 4. Bioturbation of sediments through Bivalve movements increases sediment water and oxygen content and releases nutrients from the sediment to the water column. The physical presence of Bivalve shells creates habitat for epiphytic and epizoic organisms, and stabilizes sediment and provides refugia for benthic fauna. Biodeposition of faeces and pseudofaeces can alter the composition of benthic communities. 5. There is conflicting evidence concerning the role of resource limitation in structuring Bivalve communities. Control by Bivalves of primary production is most likely when their biomass is large relative to the water volume and where hydrologic residence time is long. Future studies should consider exactly what Bivalves feed upon, whether feeding varies seasonally and with habitat, and whether significant overlap in diet occurs. In particular, we need a clearer picture of the importance of suspension versus deposit feeding and the potential advantages and tradeoffs between these two feeding modes. 6. In North America, native burrowing Bivalves (Unionidae) are declining at a catastrophic rate. This significant loss of benthic biomass, coupled with the invasion of an exotic burrowing Bivalve (Corbicula), may result in large alterations of ecosystem processes and functions.

Patricia Mirella Da Silva - One of the best experts on this subject based on the ideXlab platform.

  • Effects of marine Harmful Algal Blooms on Bivalve cellular immunity and infectious diseases: a review
    Developmental and Comparative Immunology, 2020
    Co-Authors: Malwenn Lassudrie, Helene Hegaret, Gary Wikfors, Patricia Mirella Da Silva
    Abstract:

    Bivalves were long thought to be “symptomless carriers” of marine microalgal toxins to human seafood consumers. In the past three decades, science has come to recognize that harmful algae and their toxins can be harmful to grazers, including Bivalves. Indeed, studies have shown conclusively that some microalgal toxins function as active grazing deterrents. When responding to marine Harmful Algal Bloom (HAB) events, Bivalves can reject toxic cells to minimize toxin and bioactive extracellular compound (BEC) exposure, or ingest and digest cells, incorporating nutritional components and toxins. Several studies have reported modulation of Bivalve hemocyte variables in response to HAB exposure. Hemocytes are specialized cells involved in many functions in Bivalves, particularly in immunological defense mechanisms. Hemocytes protect tissues by engulfing or encapsulating living pathogens and repair tissue damage caused by injury, poisoning, and infections through inflammatory processes. The effects of HAB exposure observed on Bivalve cellular immune variables have raised the question of possible effects on susceptibility to infectious disease. As science has described a previously unrecognized diversity in microalgal bioactive substances, and also found a growing list of infectious diseases in Bivalves, episodic reports of interactions between harmful algae and disease in Bivalves have been published. Only recently, studies directed to understand the physiological and metabolic bases of these interactions have been undertaken. This review compiles evidence from studies of harmful algal effects upon Bivalve shellfish that establishes a framework for recent efforts to understand how harmful algae can alter infectious disease, and particularly the fundamental role of cellular immunity, in modulating these interactions. Experimental studies reviewed here indicate that HABs can modulate Bivalve-pathogen interactions in various ways, either by increasing Bivalve susceptibility to disease or conversely by lessening infection proliferation or transmission. Alteration of immune defense and global physiological distress caused by HAB exposure have been the most frequent reasons identified for these effects on disease. Only few studies, however, have addressed these effects so far and a general pattern cannot be established. Other mechanisms are likely involved but are under-studied thus far and will need more attention in the future. In particular, the inhibition of Bivalve filtration by HABs and direct interaction between HABs and infectious agents in the seawater likely interfere with pathogen transmission. The study of these interactions in the field and at the population level also are needed to establish the ecological and economical significance of the effects of HABs upon Bivalve diseases. A more thorough understanding of these interactions will assist in development of more effective management of Bivalve shellfisheries and aquaculture in oceans subjected to increasing HAB and disease pressures.

Timothy J. Hoellein - One of the best experts on this subject based on the ideXlab platform.

Eva Philipp - One of the best experts on this subject based on the ideXlab platform.

  • Bivalve models of aging and the determination of molluscan lifespans
    Experimental Gerontology, 2009
    Co-Authors: Doris Abele, Thomas Brey, Eva Philipp
    Abstract:

    Bivalves are newly discovered models of natural aging. This invertebrate group includes species with the longest metazoan lifespan approaching 400 years, as well as species of swimming and sessile lifestyles that live just for 1 year. Bivalves from natural populations can be aged by shell growth bands formed at regular intervals of time. This enables the study of abiotic and biotic environment factors (temperature, salinity, predator and physical disturbance) on senescence and fitness in natural populations, and distinguishes the impact of extrinsic effectors from intrinsic (genetic) determinantes of animal aging. Extreme longevity of some Bivalve models may help to analyze general metabolic strategies thought to be life prolonging, like the transient depression of metabolism, which forms part of natural behaviour in these species. Thus, seasonal food shortage experienced by benthic filter feeding Bivalves in polar and temperate seas may mimic caloric restriction in vertebrates. Incidence of malignant neoplasms in Bivalves needs to be investigated, to determine the implication of late acting mutations for Bivalve longevity. Finally, Bivalves are applicable models for testing the implication of heterozygosity of multiple genes for physiological tolerance, adaptability (heterozygote superiority), and life expectancy.

  • Bivalve models of aging and the determination of molluscan lifespans
    Experimental gerontology, 2009
    Co-Authors: Doris Abele, Thomas Brey, Eva Philipp
    Abstract:

    Bivalves are newly discovered models of natural aging. This invertebrate group includes species with the longest metazoan lifespan approaching 400 y, as well as species of swimming and sessile lifestyles that live just for 1 y. Bivalves from natural populations can be aged by shell growth bands formed at regular intervals of time. This enables the study of abiotic and biotic environment factors (temperature, salinity, predator and physical disturbance) on senescence and fitness in natural populations, and distinguishes the impact of extrinsic effectors from intrinsic (genetic) determinants of animal aging. Extreme longevity of some Bivalve models may help to analyze general metabolic strategies thought to be life prolonging, like the transient depression of metabolism, which forms part of natural behaviour in these species. Thus, seasonal food shortage experienced by benthic filter feeding Bivalves in polar and temperate seas may mimic caloric restriction in vertebrates. Incidence of malignant neoplasms in Bivalves needs to be investigated, to determine the implication of late acting mutations for Bivalve longevity. Finally, Bivalves are applicable models for testing the implication of heterozygosity of multiple genes for physiological tolerance, adaptability (heterozygote superiority), and life expectancy.