• ALGAE
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• v.27 no.1
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• pp.43-54
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• 2012

A mathematical model of the commercial harvest of Palmaria palmata (Dulse) is presented based on a logistic model and field data collected on Digby Neck, Nova Scotia from 14 harvested shores during May to August, 2010. Field observations used to estimate model parameters included cover of Dulse before and after harvest from Dulse dominated boulders for which surface area was estimated, and from which fresh biomass of harvested Dulse was weighed. Over all the surveys the average harvest fraction was about 50%, and the total resource was about $1,600g\;m^{-2}$. With growth rates in excess of 4% per day and a 50% harvest of the standing crop each month, the model suggests that the Dulse resource is sustainable at current harvest levels.

• Applied Biological Chemistry
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• v.6
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• pp.119-121
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• 1965

• Nuclear Engineering and Technology
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• v.10 no.1
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• pp.13-25
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• 1978

The present paper deals with the measurement of the environmental radioactivity at the Kori nuclear Power Plant site area for the Period of six years from December 1970 to December 1976. Gross alpha activity was measured in samples of airborne particulate. Gross beta measurement was performed on soil, water, airborne perticulate, pine needle, precipitation, fallout (gummed acetate paper) and various foodstuffs. Radioactivities of strontium-90 and cesium-l37 were determined by means of radiochemical analyses in samples of spinach, cabbage, barley, rice in terrestrial food, sea eel, shell fish, dulse, green laver in marine product and milk, and of fallout (cloumn), Furthermore, tritum was also analyzed in water sample of well, stream and sea by electrical enrichment.

• ALGAE
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• v.33 no.1
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• pp.109-125
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• 2018

Turkish towel (Chondracanthus exasperatus), Pacific dulse (Palmaria mollis, also known as Red ribbon seaweed), and sea lettuce (Ulva spp.) were cultivated in a land-based intensive culture system at the Manchester Research Station, USA from August 2013 to September 2014. Macroalgae were grown in tumble-aerated tanks, harvested bimonthly for seasonal growth calculations, and analyzed for protein, lipid, ash, and amino acid content. Growth rate of all three species exhibited a similar pattern, with the highest specific growth rates occurring during the summer months (Turkish towel: 7.8%, Pacific dulse: 8.2%, and sea lettuce: 6.2%). Growth of all three species was lowest around winter solstice; with negative growth only observed in sea lettuce. On a dry weight basis significant differences in protein content existed between the three species with highest values for sea lettuce ($29.5{\pm}1.4%$). Lipid content varied between species (0.95-2.78%) with significantly higher lipid observed in sea lettuce (0.58-4.82%). No significant differences were detected on a seasonal basis among each species. Essential amino acids accounted for $43{\pm}0.9$ to $47{\pm}1.2%$ of total amino acids with Turkish towel having the highest value. Turkish towel had a significantly higher taurine level ($0.82{\pm}0.27$) than the other macroalgae. The levels of persistent organic pollutants and heavy metals were low. The estimated annual product of the three species ranged from 50- to $70-mt\;dry\;weight\;ha^{-1}\;y^{-1}$, significantly higher than conventional crops. Land-based culture of these species can produce year-round harvest, consistent product quality, and low contaminant levels.

• ALGAE
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• v.27 no.1
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• pp.33-42
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• 2012

Population ecology of Palmaria palmata is described from the intertidal zone of Digby Neck and adjacent islands of Nova Scotia. The primary objectives were: to evaluate the difference in habitat specialization and population structure of P. palmata between harvest and non-harvest shores, and to characterize differences in thallus structure and frond sizes between epilithic and epiphytic populations. Harvest shores were gently sloping boulder fields with boulders typically about 0.5-1.0 m with dense cover of P. palmata on many of the rocks. Non-harvest shores (with or without P. palmata) consisted of boulders that were smaller or larger than harvest shores, or bedrock; when P. palmata was present on nonharvest sites it was typically epiphytic on other algae (e.g., Fucus spp., Mastocarpus stellatus, Devaleraea ramentacea). Harvestable epiphytic populations occurred only in high current areas. While there was little difference in average cover of P. palmata harvest and non-harvest shores ($31.2{\pm}13.7%$ vs. $19.4{\pm}7.3%$, mean ${\pm}$ standard deviation [SD]), the cover of P. palmata on harvest shores was highly skewed such that individual boulders often had >90% cover while adjacent rocks had little. Frond length of large fronds was greater on harvested shores, and mean frond density ($g\;m^{-2}$) was three times higher than the mean density on the non-harvested shores. Frond lengths of entire epiphytic and epilithic frond complements of 119 thalli from harvest beaches showed no difference in mean size of the largest fronds, and no difference in frond number per holdfast when epiphytic and epilithic thalli were compared.