The Experts below are selected from a list of 180 Experts worldwide ranked by ideXlab platform
Paul J Harrison - One of the best experts on this subject based on the ideXlab platform.
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ammonium and nitrate uptake by laminaria saccharina and Nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. saccharina and Nereocystis. Unlike L. saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p <0.05). Both L. saccharina and Nereocystis would be suitable for integrated cultivation of salmon/kelp.
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Ammonium and nitrate uptake by Laminaria saccharina and Nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. saccharina and Nereocystis. Unlike L. saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p
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A LOW-VOLUME FLOW TANK FOR MEASURING NUTRIENT UPTAKE BY LARGE MACROPHYTES1
Journal of Phycology, 1994Co-Authors: Catriona L. Hurd, Paul J Harrison, Michael C. Quick, Craig L. Stevens, Bernard Laval, Louis D. DruehlAbstract:A recirculating flow-tank was designed and tested to measure inorganic nutrient uptake by, and visualize the movement of seawater around, large macrophytes. The tank volume was small (46 L), and a propeller drive produced unidirectional mean flow. A turbulence reduction section dampened turbulence in the test section to a low level, so that water movement within this region was virtually laminar. The test section of the tank was wider than that of previous designs, allowing whole blades of Macrocystis integrifolia Bory and juvenile plants of Nereocystis luetkeana (Mert.) Post, et Rupr. to be placed in the flow, away from the influence of velocity boundary layers associated with the tank walls. The tank's use in macroalgae nutrient uptake and flow visualization experiments was demonstrated.
Royann J Petrell - One of the best experts on this subject based on the ideXlab platform.
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ammonium and nitrate uptake by laminaria saccharina and Nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. saccharina and Nereocystis. Unlike L. saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p <0.05). Both L. saccharina and Nereocystis would be suitable for integrated cultivation of salmon/kelp.
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Ammonium and nitrate uptake by Laminaria saccharina and Nereocystis luetkeana originating from a salmon sea cage farm
Journal of Applied Phycology, 1998Co-Authors: Royann J Petrell, Paul J HarrisonAbstract:In the laboratory, ammonium and nitrate uptakes were measured for juvenile Laminaria saccharina (L.) Lamour. and Nereocystis luetkeana (Mert.) Post. et Rupr. originating from a salmon sea cage farm in northwestern British Columbia, Canada. The effect of various concentrations of NH4+ and NO3-, which are typical of salmon farming environments, on uptakes values were examined. Both L. saccharina and Nereocystis revealed simultaneous uptake of NH4+ and NO3- when both NH4+ and NO3- were present in the medium. During a 3-h incubation, mean uptake rates of NH4+ and NO3- by L. saccharina ranged from 6.0–8.9 and 4.6–10.6 μmol gdw-1 h-1, respectively, and by Nereocystis, they ranged from 6.6–9.3 μmol gdw-1 h-1 and 6.1–17.0 μmol gdw-1 h-1, respectively. The highest uptake rates (14.8 μmol NH4+ gdw-1 h-1by L. saccharina and 27.2 μmol NO3- gdw-1 h-1 by Nereocystis) occurred at the highest concentration (40 μM NH4+ plus 30 μM NO3-) during a 1 h incubation. Nitrate uptake by both L. saccharina and Nereocystis increased linearly up to the highest nitrate level tested (30 μM), whereas uptake rates of ammonium were stable beyond 10 μM NH4+ to reach approximately 10 and 13 μmol gdw-1 h-1, respectively, for L. saccharina and Nereocystis. Unlike L. saccharina, Nereocystis showed a significant preference for NO3- when more than 20 μM NO3- was present in the medium ( p
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Integrated cultivation of salmonids and seaweeds in open systems
Hydrobiologia, 1996Co-Authors: Royann J Petrell, Sylvain Y. AlieAbstract:Critical aspects of growing Laminaria saccharina and Nereocystis luetkeana near salmon sea cages are discussed. A new computer spreadsheet model was developed, which integrated biological, physical and economic aspects of kelp/salmon cultivation, in order to provide information on production, nutrient removal, and technical and economic feasibility of different production strategies. Given a farm-gate price of $20 kg−1 (dry mass) and either a 24 or 48 sea cage salmon farm, kelp is a feasible investment option. Results of the model suggest that kelp apparently obtains ammonium for growth during slack tide and that ammonium uptake is also significant during that time. The net yield of Nereocystis needs to be increased before it can compete with the yield of Laminaria. To include kelp on a salmon farm, a part-time position and a separate mooring system for kelp would be needed. Special attention should be given to training personnel in both salmon and kelp production.
L T Carney - One of the best experts on this subject based on the ideXlab platform.
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restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats
Marine Ecology Progress Series, 2005Co-Authors: L T Carney, Terrie Klinger, Robert J Waaland, Kern EwingAbstract:Anthropogenic disturbances such as shoreline development and sediment loading can reduce or eliminate Nereocystis luetkeana populations and commercially important species associ- ated with N. luetkeana. Hence, kelp restoration will become increasingly important in urbanized nearshore areas. Techniques to establish N. luetkeana populations in the northwestern waters of Washington State, USA, were examined and compared: (1) out-planting recently settled zoospores and microscopic sporophytes (0.5 to 1.0 mm blade length) grown in laboratory culture, in the field onto natural substrate, and at elevated positions, and (2) transplanting juvenile sporophytes (<15 cm stipe length) from natural populations, bypassing the culturing phase. Juvenile transplants were found to be more successful than cultured out-plants. The restoration cost for juvenile transplants was 12 US dollars (USD) per installed plant with a maximum cost estimate of 200 USD m -2 . These had a 10 to 30% higher survival rate than previously reported kelp transplant efforts using larger individ- uals. The collection of smaller individuals for transplanting imposes smaller ecological costs to natural populations than does the collection of larger, established plants. Stipe breakage caused by the graz- ing gastropod Lacuna vincta posed the largest limiting factor on transplant survival. Lack of survival among the out-planted zoospores and microscopic sporophytes indicates that other methods will be more successful. Restoration efforts in the nearshore marine environment will benefit from an adap- tive management approach in which techniques can be tailored to the specific physical and biologi- cal conditions at the restoration site.
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Restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats
Marine Ecology Progress Series, 2005Co-Authors: L T Carney, J. Robert Waaland, Terrie Klinger, Kern EwingAbstract:Anthropogenic disturbances such as shoreline development and sediment loading can reduce or eliminate Nereocystis luetkeana populations and commercially important species associ- ated with N. luetkeana. Hence, kelp restoration will become increasingly important in urbanized nearshore areas. Techniques to establish N. luetkeana populations in the northwestern waters of Washington State, USA, were examined and compared: (1) out-planting recently settled zoospores and microscopic sporophytes (0.5 to 1.0 mm blade length) grown in laboratory culture, in the field onto natural substrate, and at elevated positions, and (2) transplanting juvenile sporophytes (
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17 restoration techniques for Nereocystis luetkeana mertens postels et ruprecht bull kelp
Journal of Phycology, 2003Co-Authors: L T CarneyAbstract:The establishment and growth of Nereocystis luetkeana communities are limited by many environmental and biotic factors. Temperature, light quantity and quality, turbidity, salinity, wave motion, and competition for space and light all determine where populations of this annual kelp will establish and persist from season to season. Like much of the nearshore marine vegetation in Puget Sound and the San Juan Archipelago, Nereocystis is negatively impacted by anthropogenic disturbances, such as shoreline development and sediment loading from terrestrial erosion. These events can alter or eliminate optimal habitat and conditions that support adult populations, as well as interfere with the development of the microscopic life stages. Various techniques to establish a Nereocystis bed in the northern waters of Washington, USA are examined and will serve as a model for future restoration efforts. Techniques being investigated are as follows: 1) out-planting Nereocystis during different seasons; 2) out-planting at different stages of maturity, i.e., zoospore and microscopic sporophyte (0.5–1.0 mm blade length) from cultures; 3) out-planting directly on natural substratum versus at elevated positions; 4) transplanting juveniles (10 cm stipe length); and, 5) seeding natural substratum with out-planted sori (sporophylls), bypassing the lab culturing phase. Results of this study will help define the optimal restoration procedure, including environmental parameters, for Nereocystis in order to aid coastal managers in the implementation of nearshore restoration projects. Preliminary results will be presented.
J. Robert Waaland - One of the best experts on this subject based on the ideXlab platform.
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Restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats
Marine Ecology Progress Series, 2005Co-Authors: L T Carney, J. Robert Waaland, Terrie Klinger, Kern EwingAbstract:Anthropogenic disturbances such as shoreline development and sediment loading can reduce or eliminate Nereocystis luetkeana populations and commercially important species associ- ated with N. luetkeana. Hence, kelp restoration will become increasingly important in urbanized nearshore areas. Techniques to establish N. luetkeana populations in the northwestern waters of Washington State, USA, were examined and compared: (1) out-planting recently settled zoospores and microscopic sporophytes (0.5 to 1.0 mm blade length) grown in laboratory culture, in the field onto natural substrate, and at elevated positions, and (2) transplanting juvenile sporophytes (
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Conchospore production and seasonal occurrence of some Porphyra species (Bangiales, Rhodophyta) in Washington State
Hydrobiologia, 1990Co-Authors: J. Robert Waaland, Leal G. Dickson, Ellen C. S. DuffieldAbstract:The leafy thalli of species of the marine red algal genus Porphyra grow rapidly but persist for a relatively short time on rocky intertidal or subtidal substrata or as epiphytes on other marine plants. In most species, the large, short-lived leafy thalli alternate with small, presumably perennial, filamentous ‘conchocelis’ plants. Depending on the species of northeastern Pacific Porphyra , photoperiod and temperature are important regulators of conchospore formation and release. Data from laboratory studies of conchospore formation and release in five Washington species of Porphyra ( P. abottae , P. Nereocystis , P. perforata , P. pseudolanceolata and P. torta ) indicate that conchospores are most likely to be released at a time that precedes the appearance of the leafy thalli in the field.
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Protoplast isolation and regeneration in the marine red alga Porphyra Nereocystis
Planta, 1990Co-Authors: J. Robert Waaland, Leal G. Dickson, Bruce A. WatsonAbstract:We have developed a method for isolating viable protoplasts from the blade phase of the epiphytic marine red alga Porphyra Nereocystis Anderson, using a two-step enzymatic digestion with commercially available enzymes. The first step uses papain, the second step uses abalone acetone powder. The method is rapid and gives a high yield of viable protoplasts. In liquid culture in enriched seawater medium, the protoplasts can undergo regeneration along three pathways: they directly form filaments resembling the conchocelis phase of Porphyra ; they form calli with relatively thick-walled, pigmented cells; and they indirectly form blades from the edges of these calli. Porphyra Nereocystis protoplasts also may serve as an alternative propagation method in aquaculture and be useful for studies of cell-wall formation, cell division, and thallus differentiation. They may also be used in somatic selection, somatic hybridization and gene-transfection experiments.
Kern Ewing - One of the best experts on this subject based on the ideXlab platform.
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Restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats
Marine Ecology Progress Series, 2005Co-Authors: L T Carney, J. Robert Waaland, Terrie Klinger, Kern EwingAbstract:Anthropogenic disturbances such as shoreline development and sediment loading can reduce or eliminate Nereocystis luetkeana populations and commercially important species associ- ated with N. luetkeana. Hence, kelp restoration will become increasingly important in urbanized nearshore areas. Techniques to establish N. luetkeana populations in the northwestern waters of Washington State, USA, were examined and compared: (1) out-planting recently settled zoospores and microscopic sporophytes (0.5 to 1.0 mm blade length) grown in laboratory culture, in the field onto natural substrate, and at elevated positions, and (2) transplanting juvenile sporophytes (
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restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats
Marine Ecology Progress Series, 2005Co-Authors: L T Carney, Terrie Klinger, Robert J Waaland, Kern EwingAbstract:Anthropogenic disturbances such as shoreline development and sediment loading can reduce or eliminate Nereocystis luetkeana populations and commercially important species associ- ated with N. luetkeana. Hence, kelp restoration will become increasingly important in urbanized nearshore areas. Techniques to establish N. luetkeana populations in the northwestern waters of Washington State, USA, were examined and compared: (1) out-planting recently settled zoospores and microscopic sporophytes (0.5 to 1.0 mm blade length) grown in laboratory culture, in the field onto natural substrate, and at elevated positions, and (2) transplanting juvenile sporophytes (<15 cm stipe length) from natural populations, bypassing the culturing phase. Juvenile transplants were found to be more successful than cultured out-plants. The restoration cost for juvenile transplants was 12 US dollars (USD) per installed plant with a maximum cost estimate of 200 USD m -2 . These had a 10 to 30% higher survival rate than previously reported kelp transplant efforts using larger individ- uals. The collection of smaller individuals for transplanting imposes smaller ecological costs to natural populations than does the collection of larger, established plants. Stipe breakage caused by the graz- ing gastropod Lacuna vincta posed the largest limiting factor on transplant survival. Lack of survival among the out-planted zoospores and microscopic sporophytes indicates that other methods will be more successful. Restoration efforts in the nearshore marine environment will benefit from an adap- tive management approach in which techniques can be tailored to the specific physical and biologi- cal conditions at the restoration site.