The Experts below are selected from a list of 310146 Experts worldwide ranked by ideXlab platform
Torstein Kristensen - One of the best experts on this subject based on the ideXlab platform.
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Freshwater treatment of amoebic gill disease and sea lice in seawater salmon production considerations of water chemistry and fish welfare in norway
Aquaculture, 2015Co-Authors: Mark D Powell, Patric Reynolds, Torstein KristensenAbstract:Abstract Amoebic gill disease (AGD) and sea lice are two of the most significant disease issues that the Norwegian Atlantic salmon aquaculture industry is facing. Although both diseases respond to various extents, to Freshwater treatment, the chemistry, interactions, and efficacy of treatment can be variable. These variations can have significant impacts upon the success and failure of treatment and costs to the production cycle. Although it is known that soft Freshwater is most effective in bathing of Atlantic salmon with AGD and that most of the Freshwaters in Norway fall into the soft category, the low alkalinity and buffering capacity of such waters may impact on the pH and metal toxicity of the water source in use. Similarly dissolved organic carbon can be beneficial in treatment, although sequestration of metal ions can be reversed as the water pH drops due to high densities of fish and accumulations of carbon dioxide. Alternative treatments such as the use of oxidative disinfectants such as hydrogen peroxide used for AGD and sea lice control may have potential although the interactions in seawater with organic loads and dissolved organic carbon are unclear. Similarly the use of oxidative disinfectants in Freshwater will depend upon the water chemistry and interactions with treatment chemicals, fish, and water organic content. The logistics of treating large biomasses of Atlantic salmon on marine farms are challenging. The use of well boats offers potential although maintaining water quality during treatments is essential for both AGD and sea lice treatments to optimize fish welfare and treatment efficacy.
Mark D Powell - One of the best experts on this subject based on the ideXlab platform.
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Freshwater treatment of amoebic gill disease and sea lice in seawater salmon production considerations of water chemistry and fish welfare in norway
Aquaculture, 2015Co-Authors: Mark D Powell, Patric Reynolds, Torstein KristensenAbstract:Abstract Amoebic gill disease (AGD) and sea lice are two of the most significant disease issues that the Norwegian Atlantic salmon aquaculture industry is facing. Although both diseases respond to various extents, to Freshwater treatment, the chemistry, interactions, and efficacy of treatment can be variable. These variations can have significant impacts upon the success and failure of treatment and costs to the production cycle. Although it is known that soft Freshwater is most effective in bathing of Atlantic salmon with AGD and that most of the Freshwaters in Norway fall into the soft category, the low alkalinity and buffering capacity of such waters may impact on the pH and metal toxicity of the water source in use. Similarly dissolved organic carbon can be beneficial in treatment, although sequestration of metal ions can be reversed as the water pH drops due to high densities of fish and accumulations of carbon dioxide. Alternative treatments such as the use of oxidative disinfectants such as hydrogen peroxide used for AGD and sea lice control may have potential although the interactions in seawater with organic loads and dissolved organic carbon are unclear. Similarly the use of oxidative disinfectants in Freshwater will depend upon the water chemistry and interactions with treatment chemicals, fish, and water organic content. The logistics of treating large biomasses of Atlantic salmon on marine farms are challenging. The use of well boats offers potential although maintaining water quality during treatments is essential for both AGD and sea lice treatments to optimize fish welfare and treatment efficacy.
David C Aldridge - One of the best experts on this subject based on the ideXlab platform.
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microplastics in Freshwater systems a review of the emerging threats identification of knowledge gaps and prioritisation of research needs
Water Research, 2015Co-Authors: Dafne Eerkesmedrano, Richard C. Thompson, David C AldridgeAbstract:Plastic contamination is an increasing environmental problem in marine systems where it has spread globally to even the most remote habitats. Plastic pieces in smaller size scales, microplastics (particles <5 mm), have reached high densities (e.g., 100,000 items per m(3)) in waters and sediments, and are interacting with organisms and the environment in a variety of ways. Early investigations of Freshwater systems suggest microplastic presence and interactions are equally as far reaching as are being observed in marine systems. Microplastics are being detected in Freshwaters of Europe, North America, and Asia, and the first organismal studies are finding that Freshwater fauna across a range of feeding guilds ingest microplastics. Drawing from the marine literature and these initial Freshwater studies, we review the issue of microplastics in Freshwater systems to summarise current understanding, identify knowledge gaps and suggest future research priorities. Evidence suggests that Freshwater systems may share similarities to marine systems in the types of forces that transport microplastics (e.g. surface currents); the prevalence of microplastics (e.g. numerically abundant and ubiquitous); the approaches used for detection, identification and quantification (e.g. density separation, filtration, sieving and infrared spectroscopy); and the potential impacts (e.g. physical damage to organisms that ingest them, chemical transfer of toxicants). Differences between Freshwater and marine systems include the closer proximity to point sources in Freshwaters, the typically smaller sizes of Freshwater systems, and spatial and temporal differences in the mixing/transport of particles by physical forces. These differences between marine and Freshwater systems may lead to differences in the type of microplastics present. For example, rivers may show a predictable pattern in microplastic characteristics (size, shape, relative abundance) based on waste sources (e.g. household vs. industrial) adjacent to the river, and distance downstream from a point source. Given that the study of microplastics in Freshwaters has only arisen in the last few years, we are still limited in our understanding of 1) their presence and distribution in the environment; 2) their transport pathways and factors that affect distributions; 3) methods for their accurate detection and quantification; 4) the extent and relevance of their impacts on aquatic life. We also do not know how microplastics might transfer from Freshwater to terrestrial ecosystems, and we do not know if and how they may affect human health. This is concerning because human populations have a high dependency on Freshwaters for drinking water and for food resources. Increasing the level of understanding in these areas is essential if we are to develop appropriate policy and management tools to address this emerging issue.
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microplastics in Freshwater systems a review of the emerging threats identification of knowledge gaps and prioritisation of research needs
Water Research, 2015Co-Authors: Dafne Eerkesmedrano, Richard C. Thompson, David C AldridgeAbstract:Abstract Plastic contamination is an increasing environmental problem in marine systems where it has spread globally to even the most remote habitats. Plastic pieces in smaller size scales, microplastics (particles 3 ) in waters and sediments, and are interacting with organisms and the environment in a variety of ways. Early investigations of Freshwater systems suggest microplastic presence and interactions are equally as far reaching as are being observed in marine systems. Microplastics are being detected in Freshwaters of Europe, North America, and Asia, and the first organismal studies are finding that Freshwater fauna across a range of feeding guilds ingest microplastics. Drawing from the marine literature and these initial Freshwater studies, we review the issue of microplastics in Freshwater systems to summarise current understanding, identify knowledge gaps and suggest future research priorities. Evidence suggests that Freshwater systems may share similarities to marine systems in the types of forces that transport microplastics (e.g. surface currents); the prevalence of microplastics (e.g. numerically abundant and ubiquitous); the approaches used for detection, identification and quantification (e.g. density separation, filtration, sieving and infrared spectroscopy); and the potential impacts (e.g. physical damage to organisms that ingest them, chemical transfer of toxicants). Differences between Freshwater and marine systems include the closer proximity to point sources in Freshwaters, the typically smaller sizes of Freshwater systems, and spatial and temporal differences in the mixing/transport of particles by physical forces. These differences between marine and Freshwater systems may lead to differences in the type of microplastics present. For example, rivers may show a predictable pattern in microplastic characteristics (size, shape, relative abundance) based on waste sources (e.g. household vs. industrial) adjacent to the river, and distance downstream from a point source. Given that the study of microplastics in Freshwaters has only arisen in the last few years, we are still limited in our understanding of 1) their presence and distribution in the environment; 2) their transport pathways and factors that affect distributions; 3) methods for their accurate detection and quantification; 4) the extent and relevance of their impacts on aquatic life. We also do not know how microplastics might transfer from Freshwater to terrestrial ecosystems, and we do not know if and how they may affect human health. This is concerning because human populations have a high dependency on Freshwaters for drinking water and for food resources. Increasing the level of understanding in these areas is essential if we are to develop appropriate policy and management tools to address this emerging issue.
Patric Reynolds - One of the best experts on this subject based on the ideXlab platform.
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Freshwater treatment of amoebic gill disease and sea lice in seawater salmon production considerations of water chemistry and fish welfare in norway
Aquaculture, 2015Co-Authors: Mark D Powell, Patric Reynolds, Torstein KristensenAbstract:Abstract Amoebic gill disease (AGD) and sea lice are two of the most significant disease issues that the Norwegian Atlantic salmon aquaculture industry is facing. Although both diseases respond to various extents, to Freshwater treatment, the chemistry, interactions, and efficacy of treatment can be variable. These variations can have significant impacts upon the success and failure of treatment and costs to the production cycle. Although it is known that soft Freshwater is most effective in bathing of Atlantic salmon with AGD and that most of the Freshwaters in Norway fall into the soft category, the low alkalinity and buffering capacity of such waters may impact on the pH and metal toxicity of the water source in use. Similarly dissolved organic carbon can be beneficial in treatment, although sequestration of metal ions can be reversed as the water pH drops due to high densities of fish and accumulations of carbon dioxide. Alternative treatments such as the use of oxidative disinfectants such as hydrogen peroxide used for AGD and sea lice control may have potential although the interactions in seawater with organic loads and dissolved organic carbon are unclear. Similarly the use of oxidative disinfectants in Freshwater will depend upon the water chemistry and interactions with treatment chemicals, fish, and water organic content. The logistics of treating large biomasses of Atlantic salmon on marine farms are challenging. The use of well boats offers potential although maintaining water quality during treatments is essential for both AGD and sea lice treatments to optimize fish welfare and treatment efficacy.
Ronald Sluys - One of the best experts on this subject based on the ideXlab platform.
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african planarians morphology and karyology of dugesia maghrebiana sp n platyhelminthes tricladida from tunisia
Italian Journal of Zoology, 2009Co-Authors: Giacinta Angela Stocchino, Renata Manconi, Ronald Sluys, Giovanni Corso, Salvatore Casu, Maria PalaAbstract:Extensive surveys were made of Tunisian Freshwaters, yielding Freshwater planarians at only one locality in southeastern Tunisia, representing a new species. Dugesia maghrebiana sp. n. is characterized by the presence of the following features: ventral course of the ejaculatory duct, terminal opening of the ejaculatory duct, double diaphragm, symmetrical openings of the oviducts into the bursal canal, and by a typical condition of mixoploidy with a double aneuploidic chromosome complement. The taxonomic position of the new species is discussed in relation to other African and Mediterranean species.
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african planarians morphology and karyology of dugesia maghrebiana sp n platyhelminthes tricladida from tunisia
Italian Journal of Zoology, 2009Co-Authors: Giacinta Angela Stocchino, Renata Manconi, Ronald Sluys, Giovanni Corso, Salvatore Casu, Maria PalaAbstract:Extensive surveys were made of Tunisian Freshwaters, yielding Freshwater planarians at only one locality in southeastern Tunisia, representing a new species. Dugesia maghrebiana sp. n. is characterized by the presence of the following features: ventral course of the ejaculatory duct, terminal opening of the ejaculatory duct, double diaphragm, symmetrical openings of the oviducts into the bursal canal, and by a typical condition of mixoploidy with a double aneuploidic chromosome complement. The taxonomic position of the new species is discussed in relation to other African and Mediterranean species.
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global diversity of free living flatworms platyhelminthes turbellaria in Freshwater
Hydrobiologia, 2008Co-Authors: Ernest R Schockaert, Matthew D Hooge, Steve Schilling, Seth Tyler, Ronald Sluys, Tom ArtoisAbstract:This contribution reviews diversity of turbellarian species by biogeographical regions, with comments on species biology. The review draws on the database available at http://www.devbio.umesci.maine.edu/styler/turbellaria. Comparisons between regions suggest that species richness may be at least one order of magnitude higher than the currently reported number of species. In the context of the recent reconstructions of phylogeny of Platyhelminthes based on molecular data, the paper allows inferences as to the history of colonization of Freshwaters by turbellarians. Specifically, four, or perhaps six, major invasions of Freshwater habitats may have occurred in the Pangean period, each of which gave rise to a monophyletic Freshwater taxon. In addition, several occasional invasions by representatives of marine taxa must have taken place.
