scholarly journals A new grid-net design to eliminate by-catch for the veined rapa whelk beam trawl fisheries in the south-eastern Black Sea

2018 ◽  
Author(s):  
AHMET RAIF ERYAŞAR
Keyword(s):  
Black Sea ◽  
The Black Sea ◽  
Beam Trawl ◽  
The South ◽  
South Eastern ◽  
Sea Beam ◽  
The Mean ◽  
By Catch ◽  
Trawl Fisheries ◽  
Rapa Whelk

            The beam trawl fisheries in the Black Sea only target the veined rapa whelk (Rapana venosa) individuals, and other species like fishes and crabs are thrown back into the sea dead or alive. Furthermore, small bivalves and crabs are packed with the target species without any elimination. In this study, a grid-net design (GND) with two different bar spacing was tested to reduce the by-catch. In total 30 hauls (15 hauls for each bar spacing) were carried out in the south-eastern Black Sea between 17 and 26 August 2017. A commercial diamond mesh and one of the grid-net beam trawls were towed simultaneously onboard a commercial vessel to compare the by-catch compositions. Results showed that there were statistically significant (p<0.01) 78% and 83% decreases in the mean weight of the by-catch for 20 and 30 mm grid-nets, respectively. When compared to the conventional gear, a commercial loss of 14% in the 20 mm GND, and 39% in the 30 mm GND in landing values were estimated. In conclusion, use of grid-nets in south-eastern Black Sea beam trawl fisheries can significantly reduce the by-catch of most benthic species. However, it also causes some commercial loss which might be compensated by providing some compensation to fishers such as extension of the fishing season.

‘Brown-Clay’ Amphorae from Gonio (Apsaros)

Światowit ◽  
2019 ◽  
Vol 57 ◽  
pp. 143-151
Author(s):  
Paulina Komar
Keyword(s):  
Black Sea ◽  
The Other ◽  
The Black Sea ◽  
Local Production ◽  
The South ◽  
South Eastern ◽  
Other Hand ◽  
C 50 ◽  
Brown Clay

This paper presents the first study of the so-called ‘brown-clay’ amphorae discovered by the Gonio-Apsaros Polish-Georgian Expedition in the Roman fort of Apsaros (modern Gonio, Georgia) between 2014 and 2018. In the course of five excavation seasons, 157 diagnostic fragments of these containers were attested, all belonging to variants Ch 1B2 and Ch 1C dated to between c. 50 BC and the 3rd century AD. Thus, they confirm the existence of the Apsaros fortress during the first three centuries of the present era. Both Colchian and south-eastern Pontic containers were found in Apsaros, the latter produced probably in Trapezus. This suggests the south-eastern Pontic provenance of some of the imports in Apsaros, especially until the end of the 1st century AD. On the other hand, local production of containers indicates that the area of the fortress might have produced food surpluses (probably wine), which during the late 1st and throughout the 2nd and 3rd centuries AD were exported to other areas neighbouring the Black Sea.

scholarly journals THE ACTIONS OF THE SOVIET AVIATION TO DISRUPT THE MARITIME TRAFFIC OF THE ENEMY DURING THE RETREAT OF THE GERMAN-ROMANIAN TROOPS IN THE SOUTH-EASTERN CRIMEA (APRIL 1944)

2019 ◽  
pp. 18-21
Author(s):  
S.N. Tkachenko
Keyword(s):  
Air Force ◽  
Black Sea ◽  
The Black Sea ◽  
The South ◽  
Fighter Aircraft ◽  
South Eastern ◽  
Maritime Traffic ◽  
Eastern Crimea

On the basis of archival sources and Chronicles of hostilities in the Black sea, data on the actions of assault and fighter aircraft of the black sea fleet air force and the 4th air army on sea targets, ports of the South-Eastern Crimea and their infrastructure when trying to evacuate the retreating German-Romanian troops in the second decade of April 1944, at the beginning of the Crimean strategic offensive.

Age, growth and mortality of anchovy Engraulis encrasicolus in the south-eastern region of the Black Sea during the 2010–2011 fishing season

2013 ◽  
Vol 93 (8) ◽  
pp. 2247-2255 ◽  
Author(s):  
N. Erdoğan Sağlam ◽  
C. Sağlam
Keyword(s):  
Black Sea ◽  
Age Groups ◽  
Total Mortality ◽  
Total Sample ◽  
The Black Sea ◽  
Eastern Region ◽  
The South ◽  
Black Sea Region ◽  
Fishing Season ◽  
South Eastern

In this research age composition, sex-ratio, growth, survival, mortality and exploitation rates were determined in the south-eastern Black Sea region of Turkey during the 2010–2011 fishing season. Anchovy in the age group 2 was the most abundant (64.06%), followed by age groups 1 (33.12%), 3 (1.80%) and 0 (1.02%). Mean length and weight of the total sample, males and females, were 11.63 ± 0.02 cm, 9.98 ± 0.04 g; 11.39 ± 0.03 cm, 9.40 ± 0.07 g; and 11.98 ± 0.02 cm, 10.73 ± 0.05 g, respectively. The mean condition factor was CF = 0.63 and the sex composition was 61.27% female, 34.40% male and 4.33% unidentified. Equations describing the relationship between length and weight, age and length, and age and weight were derived as W = 0.011 × L2.742, L(t) = 16.368*(1–e−0.425*(t +1.35)) and W(t) = 23.516*(1 –e–0.425*(t+1.35))2,747, respectively. The survival (S), instantaneous total mortality (Z), annual mortality (A), natural mortality (M) and fishing mortality (F) rates were found to be S = 5.8%, Z = 2.84 yr–1,, A = 94.2%, M = 0.66 yr−1, and F = 2.18 yr–1, respectively. The exploitation rate was calculated as 0.77, which is higher than the optimum exploitation level.

II.—The Bronze Age in Macedonia

Archaeologia ◽  
1925 ◽  
Vol 74 ◽  
pp. 73-88
Author(s):  
Stanley Casson
Keyword(s):  
Eastern Europe ◽  
Bronze Age ◽  
Black Sea ◽  
The Black Sea ◽  
Southern Europe ◽  
The South ◽  
South Eastern ◽  
South Eastern Europe ◽  
The Bronze Age

In most text-books of archaeology the section dealing with the Bronze Age in the Aegean invariably refers us to the culture of Crete and Mycenae. Under the heading of ‘South-Eastern Europe’ we are usually given an account of the Bronze Age of Hungary and the Danubian area. But between these two regions lies an area which is, as yet, almost entirely uncharted by archaeologists, an area which, from its position, is one of the most important in Southern Europe. Between the Danube and the Aegean, the Black Sea and the hills that hem in the river Vardar on its right bank, lies an area across which, by rigidly limited routes, have passed all intrusive elements from Asia and all invading elements into Asia, either by way of the South Russian Steppe or across the Dardanelles and Bosporus.

Deposition of egg capsule and larval development of Rapana venosa (Gastropoda: Muricidae) from the south-eastern Black Sea

2007 ◽  
Vol 87 (4) ◽  
pp. 953-957 ◽  
Author(s):  
H. Saglam ◽  
E. Duzgunes
Keyword(s):  
Black Sea ◽  
Egg Laying ◽  
Reproductive Pattern ◽  
The South ◽  
Rapana Venosa ◽  
Egg Capsules ◽  
South Eastern ◽  
Larval Production ◽  
The Mean ◽  
Veliger Larvae

Egg capsules and intracapsular embryos of Rapana venosa were studied to determine the reproductive pattern of this invader species in the south-eastern Black Sea. Egg deposition of R. venosa in the laboratory at 25°C was described. Egg laying began in mid-June, reached a peak in July and ended in late August in 1996. The total number of the egg capsules per whelk ranged between 197 and 999 (mean 575 ±41). The mean length of the egg capsules was 13.26 mm. Each capsule contained between 124 and 1090 embryos with a mean of 555 ±10. Mean larval production per rapa whelk was about 392,931 ±42,731. The mean size of eggs produced was 213.8 μm. Five different stages of intracapsular development were observed. Embryos developed without nurse eggs. Veliger larvae completed their intracapsular development and hatched in 22 days at 25°C.

scholarly journals Lead pollution and its sources along the Turkish coast of the Black Sea

2001 ◽  
Vol 2 (2) ◽  
pp. 33 ◽  
Author(s):  
M. UNSAL
Keyword(s):  
Black Sea ◽  
River Sediments ◽  
Danube River ◽  
Eastern Coast ◽  
The Black Sea ◽  
Western Coast ◽  
Lead Pollution ◽  
The South ◽  
South Eastern ◽  
High Lead

Lead pollution and its sources have been investigated in the south-eastern and south-western Black Sea. Surficial sediments and mussels were collected in different seasons of the year from the south-eastern and south-western Black Sea and analysed for their lead contents.In the south-eastern Black Sea sediments from the easternmost and from the central stations contained the highest lead concentrations. Sediments contained 8 to 10 times the lead concentrations of sediments from the south-west. Samples taken from rivers, streams and effluents had especially high lead concentrations. The highest lead concentrations were found in sediments collected in October and December.Lead concentrations in mussels from the south-eastern coast were comparatively lower compared to those from the south-western coast. The highest average values occurred in December and in October.In the south-western Black Sea, the highest lead concentrations in sediments were obtained in those from Inebolu, followed by those from around Zonguldak. The concentrations increased from the middle to the west of the southern Black Sea coast, possibly due to the effect of the Danube River. Sediments taken in September had the highest lead concentrations, followed by samples taken in December.Very high lead concentrations (> 10 μ g g-1) were observed in mussels from those stations where the sediments also contained high concentrations. Mussels had their highest lead concentrations in January and April.

A database of Black Sea beaches

2020 ◽  
Author(s):  
Tahsin Görmüş ◽  
Berna Ayat ◽  
Burak Aydoğan
Keyword(s):  
Black Sea ◽  
Satellite Images ◽  
Wave Climate ◽  
Marine Conservation ◽  
Coastal Hazards ◽  
The Black Sea ◽  
The South ◽  
Maximum Width ◽  
Average Width ◽  
The Mean

&lt;p&gt;Beaches are not only one of the most beautiful natural entities the world coasts, they are also habitat for various species of living creatures, barrier against coastal hazards. Their conservation is crucially important, yet the efforts seem deficient. Geographic information systems are great tools towards this aim by incorporating coastal data and visually representing them. In this study, a database for all the beaches along the Black Sea coastline is created to help the efforts on marine conservation and coastal management. 1553 beaches have been digitized as polygons using satellite images between 2013 and 2016 covering the entire Black Sea coast. Geometric properties such as area, perimeter, width, central coordinates, UTM zone, shoreline length, and bound orientation are obtained through different data collection techniques. Information related to natural properties such as estuaries, coastal structures, and settlement densities have been gathered. Results indicated that Black Sea beaches are relatively narrow. Most of them are either experienced erosion or have a vulnerability to erosion. Among all 1553 beaches, only 28 beaches have an average width wider than 100 m. In the basin, the average width of the beaches is 26.04 m, the average beach area is 70384.2 m&lt;sup&gt;2&lt;/sup&gt; and the total beach shoreline length is 2116.12 km, which covers 43% of the Black Sea coastline. The mean slope values of the beaches with a maximum width of greater than 100 m are calculated using ASTER Digital Elevation Model v2. According to this analysis, the mean slope of these 164 beaches is 7.28 degrees. An additional analysis is performed by creating a different layer for the South-western part of the basin, from approximately 5 years older satellite images. This analysis showed that, even in the short-term, beaches can experience significant area loss reaching up to 50% in a relatively high wave climate such as exists in the South-western part.&lt;/p&gt;

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