An ecological baseline for Laminaria hyperborea forests in western Ireland

The aim of this work was to evaluate the potential of ultrasound (US), alone or in combination with mild heating and/or EDTA towards reduction of As, Cd, I, and Hg content of Laminaria hyperborea. Concentrations of As, Cd, I, and Hg of 56.29, 0.596, 7340, and <0.01 mg kg−1 of dry weight, respectively, were found in L. hyperborea blades. Treatment with US at 50 °C increased approx. 2-fold the amount of As released, although did not affect significantly the content of Cd or I, as compared to control (no US) samples. Reducing the temperature to 8 °C significantly decreased the effect of US, but heating at 80 °C did not cause a significant effect as compared to treatments at 50 °C. On the other hand, treatment with 0.1 N EDTA at 50 °C enhanced the percentage of Cd released by approximately 7-fold, regardless of sonication. In the present work, the combination of US and EDTA at 50 °C for 5 min led to a significant reduction of the As (32%), Cd (52%) and I (31%) content in L. hyperborea, thus improving the product’s safety for consumers.

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Seasonal Variation of the Proximate Composition, Mineral Content, Fatty Acid Profiles and Other Phytochemical Constituents of Selected Brown Macroalgae

Marine Drugs ◽

10.3390/md19040204 ◽

2021 ◽

Vol 19 (4) ◽

pp. 204

Author(s):

Marco Garcia-Vaquero ◽

Gaurav Rajauria ◽

Marta Miranda ◽

Torres Sweeney ◽

Marta Lopez-Alonso ◽

...

Keyword(s):

Fatty Acid ◽

Mineral Content ◽

Fatty Acid Profiles ◽

Laminaria Digitata ◽

Laminaria Hyperborea ◽

Brown Macroalgae ◽

The West ◽

Macroalgal Species ◽

Mineral Profile ◽

Phytochemical Constituents

The main objective was to determine the chemical, phytochemical, fatty acid and mineral profiles of three commercially relevant brown macroalgae (Laminaria digitata, Laminaria hyperborea and Ascophyllum nodosum) collected each season for two years off the west coast of Ireland. All the chemical, phytochemical, fatty acid and minerals analysed varied significantly depending on the macroalgal species, season and year of collection. Overall, the protein contents of macroalgae were negatively correlated with carbohydrate content. Protein (2–11%) was at its highest during winter and/or spring, decreasing to a minimum during summer and/or autumn. The three macroalgal species analysed in this study had clearly differentiated fatty acid profiles. The concentration of fatty acids was higher in A. nodosum compared with both Laminaria species. The mineral profile of the three macroalgal species was rich in essential metals, particularly Ca, Mg and P, while the levels of I were approximately 9- to 10-fold higher in both Laminaria spp. compared with A. nodosum. The levels of toxic metals (Cd, Hg and Pb) in all the macroalgal species studied were low in the current study; while the levels of total As were high (49–64 mg/kg DW macroalgae) compared with previous reports.

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Heavy minerals solve structural and stratigraphic problems in Ordovician strata of the western Irish Caledonides

Geological Magazine ◽

10.1017/s0016756802007100 ◽

2003 ◽

Vol 140 (1) ◽

pp. 25-30 ◽

Cited By ~ 11

Author(s):

MARIA A. MANGE ◽

JOHN F. DEWEY ◽

DAVID T. WRIGHT

Keyword(s):

Island Arc ◽

Heavy Minerals ◽

Metamorphic Complex ◽

The South ◽

Standard Sequence ◽

Western Ireland ◽

Complex Parts ◽

Wide Horizon

Heavy minerals in Ordovician successions in western Ireland record, in the Upper Arenig Sheeffry Formation, the erosion of an ophiolite/island arc complex. The appearance of staurolite and garnet at a basin-wide horizon in the Lower Llanvirn Upper Derrylea Formation signals the unroofing of the Dalradian metamorphic complex. Parts of the Ordovician sequence on Inishturk and in two small inliers are correlated with the standard sequence with unexpected results. The garnet-, sillimanite-, and staurolite-bearing Letter Formation correlates with the Upper Derrylea Formation and, on Inishturk, heavy minerals in south-younging turbidites reveal a sinistral ramp zone, that places the Sheeffry Formation structurally above and to the south of the younger Derrylea Formation.

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Resolving discrepancies between field and modelled relative sea-level data: lessons from western Ireland

Journal of Quaternary Science ◽

10.1002/jqs.2969 ◽

2017 ◽

Vol 32 (7) ◽

pp. 957-975 ◽

Cited By ~ 6

Author(s):

Robin Edwards ◽

W. Roland Gehrels ◽

Anthony Brooks ◽

Ralph Fyfe ◽

Katie Pullen ◽

...

Keyword(s):

Sea Level ◽

Relative Sea Level ◽

Level Data ◽

Western Ireland

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Photosynthesis, translocation, and alginic acid synthesis in Laminaria digitata and Laminaria hyperborea

Canadian Journal of Botany ◽

10.1139/b72-022 ◽

1972 ◽

Vol 50 (1) ◽

pp. 169-176 ◽

Cited By ~ 21

Author(s):

Johan A. Hellebust ◽

Arne Haug

Keyword(s):

Time Course ◽

Alginic Acid ◽

Acid Synthesis ◽

Laminaria Hyperborea ◽

Short Term ◽

Fresh Weight Basis ◽

Mannuronic Acid ◽

Guluronic Acid ◽

Isolated Cortex ◽

Photosynthetic Capacities

New and old tissues of L. digitata blades have very similar photosynthetic capacities on a fresh weight basis. Very little of the photoassimilate goes into alginic acid, or other macromolecular substances in old blade tissues. Less than 1% of the photoassimilated 14C in the old blade portion of a L. digitata blade was translocated to the new blade tissues in a 5-h experiment. In contrast, there is rapid transport of photoassimilate from bark cells to cells of the underlying tissues of L. digitata and L. hyperborea stipe sections. Isolated cortex and medulla tissues of L. digitata stipes have significant photosynthetic capacities, but are probably so strongly shaded by the darkly pigmented bark cells that little photosynthesis can normally occur in these tissues.A larger proportion of the photoassimilated carbon enters alginate in the cortex and medulla than in the bark of L. digitata and L. hyperborea stipes in short-term experiments. The time course for incorporation of photosynthate into alginate in continuous and pulse-labeling experiments indicates the presence of relatively large pools of alginate precursors. A large proportion of the total 14C incorporated into alginate in short-term experiments is found in the "M–M" (mannuronic acid) and "M–G" (alternating mannuronic and guluronic acid) block components.

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Are seasonal lakes as productive as permanent lakes? A case study from Ireland

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-062 ◽

2010 ◽

Vol 67 (8) ◽

pp. 1291-1302 ◽

Cited By ~ 13

Author(s):

Helder Cunha Pereira ◽

Norman Allott ◽

Catherine Coxon

Keyword(s):

Seasonal Variation ◽

Linear Regression ◽

Chlorophyll A ◽

Algal Biomass ◽

P Limitation ◽

Underlying Causes ◽

Western Ireland ◽

Log Linear ◽

First Time

This paper compares, for the first time, nutrient levels and chlorophyll a measured in a set of seasonal lakes with those reported for permanent lakes in the literature. Twenty-two turloughs (karstic seasonal lakes) in western Ireland were sampled monthly from the onset of flooding (October) until they dried out (6 to 9 months). The turloughs showed similar levels of nutrients and chlorophyll a to those reported for Irish and international lakes. Chlorophyll a peaked between November and February in the majority of turloughs, sometimes with values higher than those measured in mesotrophic lakes in summer. A significant log-linear regression was found between total phosphorus and chlorophyll a, which suggests P limitation of algal biomass in the majority of the turloughs. The regression characteristics were not significantly different than those described in similar studies of permanent lakes. Patterns in seasonal variation of nutrients are also presented, their underlying causes being discussed in relation to their transport within catchments. Our results show that despite being predominantly winter phenomena, turloughs can be as productive as permanent lakes.

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