scholarly journals Quantitative morphological variation in Sagitta setosa Müller, 1847 (Chaetognatha) and two closely related taxa

2004 ◽  
Vol 73 (4) ◽  
pp. 305-315 ◽  
Author(s):  
Katja T.C.A. Peijnenburg ◽  
Annelies C. Pierrot-Bults
Keyword(s):  
Black Sea ◽  
North Sea ◽  
Morphological Variation ◽  
Geographical Area ◽  
Total Body Length ◽  
Morphological Characters ◽  
The Black Sea ◽  
The North ◽  
The North Sea ◽  
Few Data

This paper reviews the quantitative morphological variation published for Sagitta setosa Müller, 1847 and two other species described within the S. serosa-complex, viz., S. euxina Moltschanoff, 1909 from the Black Sea, and S. batava Biersteker & Van der Spoel, 1966 from the Scheldt Estuary (Netherlands). Data on total (body) length, caudal length, numbers of teeth and hooks, ovary length, and dimensions of fins are compared between these three taxa. Additionally, samples from the North Sea, Mediterranean, and Black Sea are compared to look for geographic differences. Specimens from the Mediterranean were smallest with relatively long caudal segments, and few teeth and hooks, whereas specimens from the Black Sea were largest with relatively short caudal segments and many teeth and hooks. Specimens from the North Sea were intermediate with regards to these characters, but ranges overlapped and there were no obvious differences in allometry. These differences may be ecophenotypic, as the warm and salty Mediterranean Sea and cool and brackish Black Sea are at opposite ends of the environmental spectrum. The dimensions related to the fins showed clearer distinction between samples from different geographical areas, and slight differences in allometry. However, few data were available and little is known about the variance within each geographical area. We found more variation in quantitative characters within S. setosa from different parts of its range than between S. setosa and either S. batava, or S. euxina. Sagitta batava conformed to S. setosa in terms of all the morphological characters considered. The data for S. setosa derived from Biersteker & Van der Spoel (1966) were atypical and were found to be based on misidentifications of S. elegans. Therefore, we concluded that S. batava cannot be considered a separate taxon. For S. euxina, the data were inconclusive. Quantitative data completely overlapped between S. setosa from the Black Sea and S. euxina, but few data of S. setosa from the Black Sea were available. Because samples were either composed entirely of S. setosa or S. euxina (depending on sampling season and depth)and there was a large variation in body lengths and relative ovary lengths, we consider it possible that these samples represent seasonal variants of one and the same species.

The River Danube: An Examination of Navigation on the River

1997 ◽  
Vol 50 (1) ◽  
pp. 77-84
Author(s):  
R. W. Cooper
Keyword(s):  
Civil War ◽  
Black Sea ◽  
North Sea ◽  
Oxford English Dictionary ◽  
Former Yugoslavia ◽  
The Black Sea ◽  
River Rhine ◽  
The North ◽  
River Danube ◽  
The North Sea

One of the definitions of Navigation that gets little attention in this Institute is ‘communication by canals and rivers’ (Oxford English Dictionary), and which our French friends call La Navigation. I have always found this subject fascinating, and have previously navigated the Rivers Mekong, Irrawaddy, Hooghly, Indus, Shatt-al-Arab, Savannah and Rhône. During the middle of 1995 I travelled by barge from the North Sea to the Black Sea via the River Rhine, the Rhein—Main—Donau—Kanal (RMDK) and the River Danube, a distance of approximately 4000 km. This voyage has only recently become possible with the opening of the connecting RMDK at the end of 1992, but has been made little use of because of the civil war in the former Yugoslavia.

scholarly journals Differentiation between two epilittoral species, Scutovertex arenocolus spec. nov. and Scutovertex pilosetosus Polderman (Acari: Oribatida) from different European coasts

Zootaxa ◽  
2009 ◽  
Vol 2153 (1) ◽  
pp. 35-54 ◽  
Author(s):  
TOBIAS PFINGSTL ◽  
SYLVIA SCHÄFFER ◽  
ERNST EBERMANN ◽  
GUENTHER KRISPER
Keyword(s):  
North Sea ◽  
Principal Component ◽  
Morphological Characters ◽  
Closely Related Species ◽  
The North ◽  
Baltic Coast ◽  
The North Sea ◽  
The One ◽  
The Baltic ◽  
Littoral Species

Scutovertex arenocolus spec. nov. living in the sandy shore of the Baltic coast is described. Additionally, a closely related species, S. pilosetosus, occurring in marsh habitats of the North Sea coast, is redescribed in detail. Both species show a similar habitus. Scutovertex arenocolus differs from S. pilosetosus in the length of body, cusps and notogastral setae, in the ridge on mentum as well as in a different exochorion structure of the eggs. A morphometric analysis of 14 morphological characters confirmed distinctly shorter cusps and notogastral setae in S. arenocolus. Additionally, a principal component analysis performed with 17 morphological traits provided a clear separation of these two species and of S. minutus. The results of these analyses lead to the conclusion that earlier reports of S. minutus in the coastal zone of the Atlantic, the Baltic and the North Sea should be assigned to the one or the other of these two littoral species.

scholarly journals XII.—On the Carboniferous Volcanic Rocks of the Basin of the Firth of Forth—their Structure in the Field and under the Microscope

1880 ◽  
Vol 29 (1) ◽  
pp. 437-518 ◽  
Author(s):  
Geikie
Keyword(s):  
North Sea ◽  
Geographical Area ◽  
Volcanic Rocks ◽  
The South ◽  
The West ◽  
Red Sandstone ◽  
Lower Silurian ◽  
The North ◽  
The North Sea ◽  
Firth Of Forth

The geographical area embraced in the present memoir forms a well-marked basin traversed along its centre by the estuary of the Forth. It is bounded on the north by the chain of the Ochil Hills, on the south by the range of the Pentland and Lammermuir uplands. Towards the west it joins along a low watershed the basin of the Clyde, while eastwards it dips under the waters of the North Sea. Within this defined space the Carboniferous rocks occupy what may be described as one great synclinal trough, varied by innumerable smaller synclines and anticlines. Save where cut out by powerful dislocations, their lower members rise up along the margins of the basin, while their highest portions cover a smaller area in the centre. The older formations forming the northern and southern boundaries of the area belong chiefly to the Lower Old Red Sandstone, in the Lammermuir district to the Lower Silurian. The Carboniferous rocks everywhere rest upon them unconformably.

Diphyllobothrium stemmacephalum Cobbold, 1858 (Diphyllobothriidea) from common bottlenose dolphin, Tursiops truncatus (Montagu) from the Texas Gulf coast, USA

Zootaxa ◽  
2018 ◽  
Vol 4379 (3) ◽  
pp. 448
Author(s):  
SOPHIA M. SÁNCHEZ ◽  
LIAT Y. GOLDSTEIN ◽  
NORMAN O. DRONEN
Keyword(s):  
Black Sea ◽  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Gulf Coast ◽  
The Black Sea ◽  
Harbor Porpoise ◽  
Pilot Whale ◽  
The North ◽  
Common Bottlenose Dolphin ◽  
The North Sea

Cobbold (1858) established Diphyllobothrium Cobbold, 1858 with the description of Diphyllobothrium stemmacephalum Cobbold, 1858 from the common harbor porpoise, Phocoena phocoena (Linnaeus) (Phocoenidae), from the North Sea off Scotland. Diphyllobothrium stemmacephalum typically has been reported from a number of Phocoenidae and Delphinidae hosts from a variety of localities: common harbor porpoise from the northern Atlantic Ocean, Baltic Sea and Black sea (e.g. Cobbold, 1858; Delyamure 1955; Delyamure 1968; Delyamure 1971; Delyamure et al. 1985; Anderson, 1987); bottlenose dolphin, Tursiops truncatus (Montagu), from the Gulf of Mexico (Ward & Collins 1959), the Black sea (Delyamure et al. 1985); common harbor porpoise off Newfoundland (Brattey & Stenson 1995), the Black Sea (Krivokhizin & Birkun 1994 [see Yera et al. 2008]), off Denmark (Herreras et al. 1997); long-finned pilot whale, Globicephala melas [Traill], North Atlantic off Faroe Island (Balbuena & Raga 1993); Atlantic white-sided dolphin, Lagenorhynchus acutus [Gray], off Massachusetts (Olson & Caira 1999). 

Summary and conclusions: environmental effects of North Sea oil and gas developments

1987 ◽  
Vol 316 (1181) ◽  
pp. 669-677 ◽  
Keyword(s):  
North Sea ◽  
Oil And Gas ◽  
Oil Pollution ◽  
Marine Pollution ◽  
Geographical Area ◽  
Benthic Fauna ◽  
Social Consequences ◽  
Offshore Platforms ◽  
The North ◽  
The North Sea

This Royal Society Discussion Meeting has examined the total environmental impact of a whole industry in a single geographical area. Land-based developments related to the exploitation of the North Sea oilfields and their social consequences have been substantial, although neither the worst fears nor the best hopes have been realized. An accommodation has been reached with the fishing industry in the affected area. Offshore platforms are a source of chronic pollution from production water, but in recent years there has been a marked increase in the use of oil-based drilling muds and it is estimated that 20 Mt per year of petroleum hydrocarbons are added to the sea in oil-contaminated drill cuttings. The effect of these additions has been studied in the laboratory, in mesocosms and in field surveys which, together, yield a consistent picture. Within a radius of a few hundred metres of a platform there is impoverishment of the benthic fauna. Close to the platform the production of anoxic conditions through smothering and the activity of sulphide-producing bacteria is probably more significant than the toxic effect of the oil-based muds. Outside this immediate zone of impact, the oil results in organic enrichment and enhanced populations of some of the fauna. The total area affected is, in the context of the North Sea, minuscule. There is no evidence that plankton is materially affected and the success of commercial fisheries dependent upon the plankton crop is more influenced by fishery practices than by any other factor. Seabird populations, about which there was formerly much concern, have not so far been affected by oil pollution in the North Sea. There is wide fluctuation in recruitment success, but populations of species thought most vulnerable to oil pollution are generally increasing. Although marine pollution research has yielded valuable insights into the responses of individuals, populations and communities to perturbation, natural as well as man-made, it is not likely that future problems associated with oil extraction from the sea will be as stimulating to fundamental research. Different problems relating to environmental pollution should now be addressed by marine scientists.

North Sea Nemedri Routes—A Collision Problem

1964 ◽  
Vol 17 (3) ◽  
pp. 243-250 ◽  
Author(s):  
J. H. Beattie
Keyword(s):  
World War Ii ◽  
Black Sea ◽  
North Sea ◽  
World War ◽  
Kerguelen Islands ◽  
The North ◽  
Northern European ◽  
Collision Problem ◽  
The World ◽  
The North Sea

In the discussion which followed the Institute's proposal on routing, Captain Oudet proposed that the collision problem should be investigated in other areas where the risk was known to be high. This paper discusses the origin of NEMEDRI routes and the collision problem on specific NEMEDRI routes in the North Sea.The origin of NEMEDRI (Northern European and Mediterranean Routing Instructions) routes is a matter of history and necessity, some understanding of which is necessary in any analysis of present problems, NEMEDRI routes are those swept routes through declared danger areas due to mining in World War II in North European waters, the Mediterranean and Black Sea. These routes take their name from the NEMEDRI publication issued to mariners giving the relevant hydrographic information for these particular areas. The swept routes and declared danger areas in many other areas, such as the remote Kerguelen Islands, Tonga or off Korea, have no such special publication and are notified in Notices to Mariners. The present navigational significance of the NEMEDRI routes is that they carry a very substantial amount of the world seaborne trade.

scholarly journals Chl <i>a</i> trends in European seas estimated using ocean-colour products

2012 ◽  
Vol 9 (2) ◽  
pp. 1481-1518 ◽  
Author(s):  
G. Coppini ◽  
V. Lyubarstev ◽  
N. Pinardi ◽  
S. Colella ◽  
R. Santoleri ◽  
...  
Keyword(s):  
Black Sea ◽  
The Black Sea ◽  
Ocean Colour ◽  
Chl A ◽  
The North ◽  
The North Sea ◽  
In Situ Observations ◽  
The Mediterranean ◽  
European Seas

Abstract. Ocean-colour remote-sensing products have been used to estimate Chl a trends in European seas. This work aims to develop a new indicator based on ocean-colour data for the European Environment Agency (EEA). The new indicator, called CSI023(+), produced from satellite ocean-colour products from the MyOcean Marine Core Service (www.myocean.eu) has been defined and calculated. CSI023 (+) is intended to complement the EEA CSI023 (Core Set of Indicators n.23) indicator for eutrophication, which is based on chlorophyll a (Chl a) in-situ observations. Validation of ocean-colour products has been carried out through comparison with observations of the Eionet EEA database, and we believe that such validation should continue in the future, perhaps with a dedicated data-collection exercise. Ocean colour has a much higher spatial and temporal resolution than the in-situ observations. The ocean-colour observations, however, are based on indirect measurements of the optical properties of the ocean, which are transformed to Chl a using an appropriate algorithm. This algorithm can either be a global algorithm that reproduces the average global Chl a concentrations well or one that is adjusted to specific regional conditions. In our analysis we have used both global and regional (adjusted to specific regional Mediterranean conditions) ocean-colour products, but the results highlight the fact that regional products produced with regional algorithms are recommended for the future. This work proposes a methodology for analysing trends comparable to the method EEA uses for its CSI23 indicator. Analysis has revealed the potential of ocean colour as a CSI023(+) indicator: large-scale, and in some cases even local-scale, changes appear to be captured by the satellite images even though in general the ocean-colour products underestimate the Chl a values. CSI023(+) shows, in the period 1998–2009, decreasing Chl a concentrations throughout the Black Sea, in the Eastern Mediterranean, in the southern part of the Western Mediterranean, in the English Channel and in the north part of the North Sea, whereas large areas with increasing trends are observed in the Bay of Biscay, in the North-East Atlantic regions of Ireland and the UK, in the northern part of the North Sea, in the Kattegat and in the Baltic. Specific analysis has been performed in the Mediterranean and the Black Sea: we first defined Chl a areas and then calculated the CSI023(+) for each of the Chl a areas. This last analysis reveals that about 80 % of Chl a areas do not show significant trends; increasing significant Chl a trends were detected in 3 Chl a areas in the Black Sea and 32 Chl a areas in the Mediterranean. Decreasing significant trends were detected in 6 Chl a areas in the Mediterranean and 2 Chl a areas in the Black Sea.

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