Relationship between diatoms in surface sediments of the Atlantic Ocean and the biological and physical oceanography of overlying waters

The number of diatom valves and fragments per gram of surface sediment in the Atlantic Ocean accurately reflects diatom abundance in the overlying waters, without any evidence of significant lateral drift during settling to the sea bottom. The distribution pattern of the number of resting spores per gram is similar to that for the whole and fragmented diatom valves. Fresh water diatoms and opal phytoliths are abundant in the sediments off the west coast of Africa where they have been deposited by the Trade Winds.Despite the relatively small number of core tops analyzed, the abundance and distribution patterns of diatoms in the sediments exhibit striking similarities to the patterns of primary productivity, phosphates, and annual production of silica in suspension in surface waters. Areas with high phosphate values and primary productivity and, therefore, areas of upwelling can be inferred from the quantitative distribution of diatoms in the sediments. Q-mode factor analysis, based on the abundance of forty-two species in thirty-seven core tops, produced six diatom species assemblages whose distributions provide additional information on the positions of certain water masses and major currents.Since the data on the quantitative distribution of diatom valves as well as on the diatom assemblages in the sediments of the Atlantic Ocean today allow prediction of certain water mass characteristics and circulation patterns of the overlying waters, they therefore, permit the reconstruction of paleoceanographic circulation patterns in ancient Atlantic Oceans, using the diatom distribution in sediments from dated horizons.

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Cysteine-Free Proteins in the Immunobiology of Arthropod-Borne Diseases

Journal of Biomedicine and Biotechnology ◽

10.1155/2010/171537 ◽

2010 ◽

Vol 2010 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

J. Santiago Mejia ◽

Erik N. Arthun ◽

Richard G. Titus

Keyword(s):

Plasmodium Falciparum ◽

Amino Acid ◽

Distribution Patterns ◽

Structural Features ◽

Structure And Function ◽

Cysteine Residues ◽

Distribution Analysis ◽

And Function ◽

Abundance And Distribution ◽

Host Parasite

One approach to identify epitopes that could be used in the design of vaccines to control several arthropod-borne diseases simultaneously is to look for common structural features in the secretome of the pathogens that cause them. Using a novel bioinformatics technique, cysteine-abundance and distribution analysis, we found that many different proteins secreted by several arthropod-borne pathogens, includingPlasmodium falciparum, Borrelia burgdorferi, and eight species of Proteobacteria, are devoid of cysteine residues. The identification of three cysteine-abundance and distribution patterns in several families of proteins secreted by pathogenic and nonpathogenic Proteobacteria, and not found when the amino acid analyzed was tryptophan, provides evidence of forces restricting the content of cysteine residues in microbial proteins during evolution. We discuss these findings in the context of protein structure and function, antigenicity and immunogenicity, and host-parasite relationships.

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Quantitative distribution of echinoderms (Holothuroidea, Asteroidea, Ophiuroidea, Echinoidea) in relation to organic matter in the sediment, in deep sea basins of the Atlantic Ocean

Echinodermata ◽

10.1201/9781003079224-13 ◽

2020 ◽

pp. 99-108 ◽

Cited By ~ 2

Author(s):

Myriam Sibuet

Keyword(s):

Organic Matter ◽

Atlantic Ocean ◽

Deep Sea ◽

Quantitative Distribution

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The Sinking of Another Tristan da Cunha Moss Endemic and Its Phytogeographical Consequences

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.8936 ◽

2020 ◽

Vol 89 (3) ◽

Cited By ~ 1

Author(s):

Ryszard Ochyra ◽

Vítězslav Plášek

Keyword(s):

Atlantic Ocean ◽

Southern Hemisphere ◽

Endemic Species ◽

Distribution Patterns ◽

South Atlantic ◽

South Atlantic Ocean ◽

Original Material ◽

The Third ◽

Tristan Da Cunha ◽

Central South

The original material of Isopterygium tristaniense Dixon, an endemic species of the Tristan da Cunha archipelago in the central South Atlantic Ocean, is taxonomically evaluated and some details of its morphology are illustrated. The species is found to be conspecific with the Holarctic Pseudotaxiphyllum elegans (Brid.) Z.Iwats. and it is the third record of the species in the Southern Hemisphere. The global distribution of this species is reviewed and the distribution patterns of the South Atlantic mosses are briefly discussed.

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Investigation of the abundance, distribution and composition of microplastics at coastal upwelling sites in the Atlantic Ocean

10.7287/peerj.preprints.1629v1 ◽

2016 ◽

Author(s):

La Daana K Kanhai ◽

Rick Officer ◽

Ian O'Connor ◽

Richard C Thompson

Keyword(s):

Atlantic Ocean ◽

Surface Waters ◽

Primary Productivity ◽

Null Hypothesis ◽

Latitudinal Gradient ◽

Coastal Upwelling ◽

Abundance Distribution ◽

Significant Difference ◽

Benguela Upwelling ◽

Canary Upwelling

Microplastics are an issue of international concern due to the fact that these substances may potentially threaten biota by (i) causing physical harm, (ii) transporting persistent, bioaccumulating and toxic (PBT) substances and, (iii) leaching plastic additives. Within the world’s oceans, areas which experience coastal upwelling are biota rich due to their high levels of primary productivity. The assessment of microplastic presence in areas which experience coastal upwelling is vital as it will indicate whether microplastics are an issue of concern in areas which support key biological resources. The null hypothesis of the present study is that microplastic abundance will be lower in areas where there is upwelling. As such, the present study aims to investigate whether microplastic abundance in upwelled areas in the Atlantic Ocean is significantly different from non-upwelled areas. Based on an opportunistic voyage aboard the RV Polarstern, microplastics will be sampled in sub-surface waters along a diverse latitudinal gradient in the Atlantic Ocean i.e. from Bremerhaven (Germany) to Cape Town (South Africa). Based on the proposed route, it will be possible to determine microplastic levels at two areas of coastal upwelling in the Atlantic Ocean (i) Canary Upwelling Ecosystem (CUE) and (ii) Benguela Upwelling Ecosystem (BUE). The results will then be analysed to determine whether there was a statistically significant difference between ‘upwelled areas’ and ‘non-upwelled areas’.

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Modeling the spatial structure of the endemic mara (Dolichotis patagonum) across modified landscapes

PeerJ ◽

10.7717/peerj.6367 ◽

2019 ◽

Vol 7 ◽

pp. e6367 ◽

Cited By ~ 1

Author(s):

Milagros Antún ◽

Ricardo Baldi

Keyword(s):

Spatial Structure ◽

Spatial Variation ◽

Spatial Models ◽

Distribution Patterns ◽

Negative Consequences ◽

Human Presence ◽

Species Response ◽

Conservation Actions ◽

Density Surface ◽

Abundance And Distribution

Across modified landscapes, anthropic factors can affect habitat selection by animals and consequently their abundance and distribution patterns. The study of the spatial structure of wild populations is crucial to gain knowledge on species’ response to habitat quality, and a key for the design and implementation of conservation actions. This is particularly important for a low-density and widely distributed species such as the mara (Dolichotis patagonum), a large rodent endemic to Argentina across the Monte and Patagonian drylands where extensive sheep ranching predominates. We aimed to assess the spatial variation in the abundance of maras and to identify the natural and anthropic factors influencing the observed patterns in Península Valdés, a representative landscape of Patagonia. We conducted ground surveys during the austral autumn from 2015 to 2017. We built density surface models to account for the variation in mara abundance, and obtained a map of mara density at a resolution of four km2. We estimated an overall density of 0.93 maras.km−2 for the prediction area of 3,476 km2. The location of ranch buildings, indicators of human presence, had a strong positive effect on the abundance of maras, while the significant contribution of the geographic longitude suggested that mara density increases with higher rainfall. Although human presence favored mara abundance, presumably by providing protection against predators, it is likely that the association could bring negative consequences for maras and other species. The use of spatial models allowed us to provide the first estimate of mara abundance at a landscape scale and its spatial variation at a high resolution. Our approach can contribute to the assessment of mara population abundance and the factors shaping its spatial structure elsewhere across the species range, all crucial attributes to identify and prioritize conservation actions.

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Basin-scale distribution patterns of picocyanobacterial lineages in the Atlantic Ocean

Environmental Microbiology ◽

10.1111/j.1462-2920.2007.01246.x ◽

2007 ◽

Vol 9 (5) ◽

pp. 1278-1290 ◽

Cited By ~ 102

Author(s):

Katrin Zwirglmaier ◽

Jane L. Heywood ◽

Katie Chamberlain ◽

E. Malcolm S. Woodward ◽

Mikhail V. Zubkov ◽

...

Keyword(s):

Atlantic Ocean ◽

Distribution Patterns ◽

Basin Scale

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Distribution patterns and indicators of the smooth hammerhead shark (Sphyrna zygaena) in the Atlantic Ocean

Fisheries Research ◽

10.1016/j.fishres.2018.12.015 ◽

2019 ◽

Vol 212 ◽

pp. 107-113 ◽

Cited By ~ 2

Author(s):

Catarina C. Santos ◽

Rui Coelho

Keyword(s):

Atlantic Ocean ◽

Distribution Patterns ◽

Hammerhead Shark

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Suprabenthic crustacean fauna of a denseAmpeliscacommunity from the English Channel

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400040881 ◽

1996 ◽

Vol 76 (4) ◽

pp. 909-929 ◽

Cited By ~ 18

Author(s):

Jean-Claude Dauvin ◽

Souaad Zouhiri

Keyword(s):

Atlantic Ocean ◽

Water Column ◽

Vertical Migration ◽

Fine Sand ◽

Abundant Species ◽

Sexually Dimorphic ◽

English Channel ◽

Free Swimming ◽

Sea Bottom ◽

Sea Bed

Ninety-six species (97, 677individuals) were collected over the course of 6 h in five suprabenthic sledge hauls from a very denseAmpeliscafine sand community from the Bay of Morlaix (western English Channel). All the species migrated into the water column at night (98% of the specimens collected in the suprabenthos were found in the night hauls). The 23 most abundant species collected were classified into five groups based on their height within the water column, but two groups predominated: the upper suprabenthic species, abundant at 0–80–145 m above the sea-bed; and the lower suprabenthic species which were abundant only near the sea bottom (-0–1–0–75 m high). Three different patterns of nocturnal vertical migration were distinguished based on the timing of maximum swimming activity: at dusk; at the beginning of the night; or later in the night. Sexually dimorphic patterns of free-swimming behaviour was observed inAmpeliscaand some other species of Amphipoda (Bathyporeia teniupes, Metaphoxusfultoni), and Cumacea (Bodotria pulchella, Pseudocuma longicornis), with many more males than females migrating into the water column at night. Finally, the density of suprabenthic crustaceans in nocturnal hauls was amongst the highest reported from infralittoral or circalittoral suprabenthic studies on other parts of the Atlantic Ocean sampled during spring.

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