On the systematics and ecology of interstitial ciliates of sandy beaches in North Yorkshire

1977 ◽  
Vol 57 (3) ◽  
pp. 735-760 ◽  
Author(s):  
Eike Hartwig ◽  
James G. Parker
Keyword(s):  
Marine Sediments ◽  
Sandy Beaches ◽  
British Isles ◽  
The North ◽  
Ciliate Species

The ciliates are considered to be the dominant protozoan group in the lacunar system of marine sediments and the important role which they play in the benthic ecosystem has been emphasized (Fenchel, 1969). More than 7500 ciliate species have been described (Corliss, 1974 a) and their distribution is worldwide (Agamaliev, 1967 a; Burkovsky, 1970c; Dragesco, 1960, 1965a; Kahl, 1930–35; Petran, 1967; Raikov, 1962). However, only two surveys of the interstitial ciliates of the British Isles have been carried out (El Maghraby & Perkins, 1956; Lackey & Lackey, 1963). This paper describes a study of the systematics and ecology of interstitial ciliates of the North Yorkshire coast.

scholarly journals Benthic Marine Ciliate Assemblages from Southern Brazil and Their Relationship with Seasonality and Urbanization Level

Diversity ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 16
Author(s):  
Luana D. Tarragô ◽  
Pedro M. A. Ferreira ◽  
Laura R. P. Utz
Keyword(s):  
Sandy Beaches ◽  
Swash Zone ◽  
Southern Brazil ◽  
Marine Ciliate ◽  
Urbanization Level ◽  
The North ◽  
Ciliate Species ◽  
Littoral Zones ◽  
One Year ◽  
High Level

Sandy beaches represent two-thirds of littoral zones worldwide. Complex factors such as winds, waves, and sediment characterize this environment. Ciliophora is one of the most diversified unicellular eukaryotic phyla and, in marine sediments, can reach 40 species per cm³. Despite its importance, knowledge about interstitial communities is still lacking. In the present work, we characterized the assemblage of interstitial ciliates from sandy beaches in the north coastal area of Rio Grande do Sul state, southern Brazil. Fourteen sampling sites distributed along the swash zone of seven beaches with different degrees of urban development were sampled over the course of one year. At each site, eight sediment samples were taken, and a total of 51 species distributed in 37 ciliate genera were identified. Classes Spirotrichea (29%) and Karyorelictea (21%) accounted for 50% of ciliate species richness, with the highest richness being observed within the context of an intermediately urbanized setting. Community analyses revealed that ciliate community is influenced by urbanization degree and season, with distinct assemblages occurring in highly urbanized areas. In beaches affected by a high level of human activity, disturbance effects increased diversity, while in areas showing a milder influence of urbanization, the level of disturbance may be low, resulting in lower richness.

Evidence of 8.2-ka event in Southeast Asia inferred from marginal marine sediments off Kallang River Basin, Singapore

2021 ◽  
Author(s):  
Yama Dixit ◽  
Stephen Chua ◽  
Yu Ting Yan ◽  
Adam Switzer
Keyword(s):  
River Basin ◽  
Marine Sediments ◽  
Large Scale ◽  
Southern Oscillation ◽  
Signal Propagation ◽  
Warm Pool ◽  
Seasonal Migration ◽  
Monsoon Circulation ◽  
Tropical Regions ◽  
The North

<p>The Maritime Continent (MC) is located within the Indo-Pacific Warm Pool, which is known as the largest area of warm sea surface temperatures with the highest rainfall on Earth that drives the global atmospheric and hydrologic circulation. The complex climatic system of the MC is controlled by large-scale phenomena such as the seasonal migration of the Intertropical Convergence Zone which causes the northwest and southeast monsoon circulation in the region as well as tropical Indo-Pacific climate phenomena, the Indian Ocean Dipole in the west and the El Niño-Southern Oscillation operating to the east of the MC. In addition to interactions of these climate phenomena, their influence varies across the region due to island topography and ocean–atmosphere fluxes. Despite dedicated efforts, a comprehensive picture of the impacts of abrupt climate events such as the ‘8.2 ka event’ during the Holocene on the MC has proved elusive. Here we use sedimentology and stable isotopes of benthic foraminifera collected from the marginal marine sediments off the Kallang River Basin, Singapore to reconstruct paleoenvironmental history of the early-mid Holocene. Owing to the high sedimentation rate (~4.4 mm/yr), the timing and nature of the ‘8.2 ka event’ was examined in detail in this region making this an invaluable and unique archive to study up to sub-centennial changes. Comparison of the Kallang record with other high-resolution marine and absolutely dated terrestrial archives speleothems revealed that the timing of the onset of ‘8.2 ka event’ in the western IPWP region lags the cooling in the North Atlantic and that of Asian and Indian monsoon failure, by ~100years possibly implying a north-south signal propagation. The termination of the ‘8.2 ka event’, however may have occurred near synchronously between high and low tropical regions at ~7.96ka BP possibly linked via both atmospheric and oceanic processes.</p><p> </p>

Grenadiers of the World Oceans: Biology, Stock Assessment, and Fisheries

2008 ◽  
Keyword(s):  
Deep Water ◽  
Stock Assessment ◽  
Data Availability ◽  
Biological Knowledge ◽  
Human Consumption ◽  
British Isles ◽  
The North ◽  
Mid Atlantic Ridge ◽  
Pros And Cons ◽  
A Minor

<em>Abstract</em>.—The biology and fisheries of macrourid species in the NE Atlantic are reviewed. Of about 30 species that occur within that area, the roundnose grenadier <em>Coryphaenoides rupestris </em>is one of the main target species of deep-water fisheries. Roughhead grenadier <em>Macrourus berglax </em>is a minor bycatch of other deep-water fisheries and an occasional target of some small fisheries. Other macrourid species are not commercially exploited because they are too small and/or in too deep waters, but some are also taken as accidental bycatch. There are three main fisheries for roundnose grenadier: north and west of the British Isles, Skagerrak, and Mid-Atlantic Ridge. The Skagerrak fishery is mainly for fish meal while the others are for human consumption. Due to data availability, a range of assessment methods has been trialled primarily for stocks to the north and west of the British Isles. Although uncertain, these assessments provide evidence that the stock has been severely depleted. Fisheries were largely unregulated until the early 2000s, but following repeated International Council for the Exploration of the Sea (ICES) advice, total allowable catches were introduced in 2003 together with effort and capacity regulations. Roundnose grenadier is the most studied species. It lives more than 50 years, compared to 30 years or more for roughhead grenadier. The limited knowledge of other species suggests a contrasting picture of maximum age ranging from 10 to 40 years. Taking into account the limited biological knowledge for these species, the pros and cons of the current management regime are discussed.

scholarly journals Moho depth of the British Isles: a probabilistic perspective

2020 ◽  
Vol 221 (2) ◽  
pp. 1384-1401
Author(s):  
A Licciardi ◽  
R W England ◽  
N Piana Agostinetti ◽  
K Gallagher
Keyword(s):  
Great Britain ◽  
Receiver Function ◽  
Moho Depth ◽  
British Isles ◽  
Data Types ◽  
The North ◽  
Data Driven Approach ◽  
Porcupine Basin ◽  
Reconstructed Surface ◽  
Surrounding Areas

SUMMARY We present a new Moho depth model of the British Isles and surrounding areas from the most up-to-date compilation of Moho depth estimates obtained from refraction, reflection and receiver function data. We use a probabilistic, trans-dimensional and hierarchical approach for the surface reconstruction of Moho topography. This fully data-driven approach allows for adaptive parametrization, assessment of relative importance between different data-types and uncertainties quantification on the reconstructed surface. Our results confirm the first order features of the Moho topography obtained in previous work such as deeper Moho (29–36 km) in continental areas (e.g. Ireland and Great Britain) and shallower Moho (12–22 km) offshore (e.g. in the Atlantic Ocean, west of Ireland). Resolution is improved by including recent available data, especially around the Porcupine Basin, onshore Ireland and Great Britain. NE trending features in Moho topography are highlighted above the Rockall High (about 28 km) and the Rockall Trough (with a NE directed deepening from 12 to about 20 km). A perpendicular SE oriented feature (Moho depth 26–28 km) is located between the Orkney and the Shetland, extending further SW in the North Sea. Onshore, our results highlight the crustal thinning towards the N in Ireland and an E–W oriented transition between deep (34 km) and shallow (about 28 km) Moho in Scotland. Our probabilistic results are compared with previous models showing overall differences around ±2 km, within the posterior uncertainties calculated with our approach. Bigger differences are located where different data are used between models or in less constrained areas where posterior uncertainties are high.

VIII.—Instances of Orientation in Prehistoric Monuments of the British Isles

Archaeologia ◽  
1923 ◽  
Vol 73 ◽  
pp. 193-224 ◽  
Author(s):  
Boyle Somerville
Keyword(s):  
British Isles ◽  
North West ◽  
The North

The occurrence of orientation in prehistoric structures has long been noticed. It has not, however, received from investigators much more than a passing comment, such as ‘the barrow is directed to the eastward’, or ‘the entrance to the chamber faces the north-west’. If a definite bearing is given, it is rarely stated whether it is ‘Magnetic’ (such as is obtained from a prismatic compass), or a True Bearing, i. e. an azimuth.

A late Quaternary bio- and climatostratigraphy for marine sediments in the north-central part of the North Sea

Boreas ◽  
2008 ◽  
Vol 7 (2) ◽  
pp. 91-96 ◽  
Author(s):  
REX HARLAND ◽  
DIANE M. GREGORY ◽  
MURRAY J. HUGHES ◽  
IAN P. WILKINSON
Keyword(s):  
North Sea ◽  
Marine Sediments ◽  
Late Quaternary ◽  
North Central ◽  
The North ◽  
The North Sea

The meteoric stone seen to fall near Crumlin, Co. Antrim, on September 13, 1902

1921 ◽  
Vol 19 (93) ◽  
pp. 149-162 ◽  
Author(s):  
Lazarus Fletcher
Keyword(s):  
Annual Meeting ◽  
British Association ◽  
British Isles ◽  
Lough Neagh ◽  
The North ◽  
The Earth ◽  
The Village

On Saturday, September 18, 1902, at 10.30 a.m. (Irish time), a stone coming from the sky struck the earth (let. 54° 88' 20" N., long. 6° 12' 10" W. of Greenwich) at a farm, belonging to Mr. Andrew Walker, situated in the district termed Crossbill, a mile to the north of the village of Crumlin, in which there is a station of the same name on the line of railway between Lisburn and Antrim. The place of fall is 3½ miles east of Lough Neagh, the largest lake in the British Isles, and I2 miles almost due west of Belfast, in which city nearly two thousand members of the British Association were then assembled for the annual meeting (September 10-17).

III.—The Pre-Cambrian Rocks of Wales

1893 ◽  
Vol 10 (9) ◽  
pp. 396-401
Author(s):  
Henry Hicks
Keyword(s):  
Recent Article ◽  
British Isles ◽  
The West ◽  
British Geological Survey ◽  
England And Wales ◽  
North West ◽  
The Past ◽  
The North ◽  
History Of ◽  
Lithological Character

In a recent article on the Pre-Cambrian Rocks of the British Isles in the Journal of Geology, vol. i., No. 1, Sir Archibald Geikie makes the following statement: “There cannot, I think, be now any doubt that small tracts of gneiss, quite comparable in lithological character to portions of the Lewisian rocks of the North-West of Scotland, rise to the surface in a few places in England and Wales. In the heart of Anglesey, for example, a tract of such rocks presents some striking external or scenic resemblance to the characteristic types of ground where the oldest gneiss forms the surface in Scotland and the West of Ireland.” To those who have followed the controversy which has been going on for nearly thirty years between the chiefs of the British Geological Survey and some geologists who have been working amongst the rocks in Wales, the importance of the above admission will be readily apparent; but as it is possible that some may be unable to realize what such an admission means in showing geological progress in unravelling the history of the older rocks in Wales during the past thirty years, a brief summary of the results obtained may possibly be considered useful.

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