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The first record of oilfish, Ruvettus pretiosus Cocco, 1829, (Gempylidae) from the depth of 65 m, caught off the coast of Benghazi, Libya (Southern Mediterranean), is reported herewith. The present finding appears to be an evidence of the extension in the latitude of its geographical distribution.
This article is devoted to the use of a mathematical model of a flood runoff for calculating rainfall runoff hydrographs from small catchments of the northwest coast of the Black Sea. The described model was tested and applied for the following catchments located in various geographical conditions, with various amounts of initial data: experimental catchments in Zacarpathian, the northwest of the Black Sea region – Ukraine and the Republic of Moldova, small catchments of the northern part of Vietnam, etc. This work was carried out on the basis of Moldavian Water-Balance Station databases. The development of a complex approach to a mathematical simulation of the formation of the processes of rain floods from small catchments is also given further investigation in this article. A brief description of the structure of a flood runoff spatial model from small catchments then provided. As well as this, the advantages of using radiolocation measurement of rainfall in the mathematical modeling of the formation of a flood runoff are shown. The results of construction runoff hydrographs confirm the possibility of applying this spatial model with the use of radar information. The optimization of model parameters was made with the data of 123 floods. The values of the quality criterion S/σ turned out not to exceed the value 0.8 in 81% of the considered cases of floods.
Background. The Lessepsian migrant ichthyofauna along the approximately 2000 km of the Libyan coastline has been poorly known. A comprehensive study, addressing this issue, was needed and therefore the presently reported research project is intended to close the gap, through identifying the fish species and assessing their distribution. Materials and Methods. The catches of commercial fisheries vessels were monitored and examined in a standardized procedure between January 2005 and March 2006. The project covered a total of 4273 specimens, comprising 1901 specimens of Siganus luridus, 1885 specimens of Siganus rivulatus, and 487 specimens of fourteen other Lessepsian fish species. Results. Sixteen Lessepsian fish species, representing 14 families, were recently found along the Libyan coast, two of which are considered to be first records for Libya: Herklotsichthys punctatus (Rüppell, 1837) and Liza carinata (Valenciennes, 1836). Approximately 50% of the immigrants were found along the entire stretch of the Libyan coast, 12.5% in the east and central regions, and 37.5% were restricted to the eastern part of the Libyan coast. All were found in the coastal area (1-50 m depth), 12.5% on the vegetation, 31.25% on sandy bottoms, 12.5% on rocks, while the majority of them (43.75%) were pelagic. Regarding the size, 75% were medium, 18.75% large, and 6.25% were categorized as small. Conclusion. The north African coast (west of the Nile delta)-compared with the Levantine- and Anatolian coast of the Mediterranean Sea-was considered to be settled by immigrants from the Red Sea with some delay, due to sea currents. If so, this situation has changed meanwhile at least for fishes. More than 37% of the recorded Lessepsian fish species are of commercial value, especially rabbitfish (Siganus spp.). The future research should be focussed on monitoring the stocks, especially of the commercially valuable species, regarding the biology and ecology of the Lessepsian migrants. Also, possible further additions to the fish fauna, by new invaders, should be recorded.
The present paper reports on the year-long study of atmospheric precipitation (rain and snow) composition, including nitrogen, phosphorus and mineral matter as conductivity, in ice-free area of western coast of Admiralty Bay (King George Island). The effects of the local Adelie penguin colony on nitrogen and phosphorus concentrations in atmospheric precipitation, as well as the role of wind on nitrogen and phosphorus enrichment of ice-free areas uncovered by a progressing deglaciation of the Ecology Glacier (ASPA 128) were examined. The effect of marine influence on the mineral matter level (as conductivity) in atmospheric precipitation was examined too. The determination of conductivity, nitrogen and phosphorus were assayed according to standard methods. Conductivity, nitrogen and phosphorus concentrations in atmospheric precipitation differed depending on sampling sites location, precipitation type (rain or snow), season (summer or winter), and also distance from a penguin rookery. The mean conductivity of rain and snow amounted to 189 μS cm⁻¹ and was higher in rain (up to 290 μS cm⁻¹) than in snow samples (87 μS cm⁻¹). Mean total nitrogen and total phosphorus concentrations in precipitation amounted to 0.208 mg Ndm⁻³ and 0.028 mg P dm⁻³, respectively. A higher conductivity was recorded in the precipitation transported by NNW winds (200 μS cm⁻¹), and lower in the precipitation transported by SSE winds (80 μS cm⁻¹). The seasonal variability of conductivity was characterized by a higher values during summer (320 μS cm⁻¹) and lower – during winter (90 μS cm⁻¹). The most nutrientrich samples were those collected in the centre of the penguin rookery, average values of TN and TP concentrations were 0.450 mg N dm⁻³ and 0.090 mg P dm⁻³, respectively. At the other sites concentrations of TN and TP were lower. Seasonal variabilty of nitrogen and phosphorus concentrations were usually characterized by minimal concentrations during winter and maximal – during spring or summer. The concentrations of nitrogen and phosphorus were characterized by a statistically significant negative relation along the distance from the penguin rookery and along the altitude of sampling sites. The influence of the penguin rookery on the higher concentrations of biogenic compounds caused the high concentrations of ammonium nitrogen (averaging about 0.250 mg N dm⁻³) during summer at all sampling sites, even at those, located farthest away (about 2200 m) from the penguin colony. The annual nitrogen and phosphorus loads deposited by atmospheric precipitation onto the ice-free area were estimated at about 0.752 kg N ha⁻¹ and 0.061 kg P ha⁻¹, respectively.
A description is provided of Longidorus balticus sp. nov., a bisexual species recovered from the rhizosphere of Elymns arenarias L. growing in coastal sand dunes in northeast Poland. The species is characterized by having a long (L=6.7-9.2 mm) and slender (a= 119-175) body; expanded labial region, flattened anteriorly; assymetrically bilobed amphids; anteriorly situated guide ring (23-29 µm); odontostyle of medium length (91-105 µm); and a short, rounded tail. Males having spicules of medium size (58-69 µm), and a row of 9-15 supplements. Longidorus baltieus sp. nov. has four juvenile developmental stages. Longidorus balticus sp. nov. resembles L. vineacola, L. belloi, L. lusitaniens, L. moesicus, L. profundorum and L. apulus.
Variations in lipid, protein and carbohydrate contents of Enteromorpha spp. were examined over a seven-month period from April to October 1993. The samples were collected from seven sampling stations along the Gulf of Gdańsk coast. The lipid content was low and varied slightly from 3.47±1.76% of DW at Puck to 4.36±2.17% of DW at Rewa and Chałupy. The protein content varied from 9.42±4.62% of DW at Puck to 20.60±5.00% of DW at Jurata. At the remaining stations the values vary over a narrow range. The maximum protein contents were recorded at the beginning and end of the growing season. The level of carbohydrate was very high compared to that of lipid and protein and varied from 29.09±6.44% of DW at Osłonino to 39.81±11.15% of DW at Puck. Seasonal carbohydrate changes were noted at all sampling stations, the minimum occurring in spring and autumn and the maximum in summer.
This paper describes the weather conditions on the NE coast of Sørkappland (South Spitsbergen) during August 2005, and considers them in the context of the general synoptic situation over the North Atlantic. A comparison of local climates features for the East and West coast of southern Spitsbergen shows that the general atmospheric circulation and direct solar radiation in summer are the decisive factors affecting weather on the East coast. Foehn effects were observed during the study period. In the East, these were triggered by the westerly cyclonic situation and, in the West, by the easterly. The differences in the intensity of foehn effects may be explained by a specific relief of the Sørkappland peninsula.
Blooms of Noctiluca scintillans are reported for the first time in the Red Sea off the south-western coasts of Saudi Arabia. During the present study, surface water samples were collected weekly on the coasts of the Al Shuqayq region from February to April 2004–2006. The abundance of N. scintillans correlated negatively with most nutrients, as well as the cell densities of diatoms and dinoflagellate species. Microscopic examination of live cells from Noctiluca blooms showed the presence of some species of diatoms and dinoflagellates within the Noctiluca body – confirmation of its grazing on these microalgae. The presence of a Noctiluca bloom in the coastal waters off south-western Saudi Arabia could be linked indirectly to water eutrophication by an increase in prey abundance. The physico-chemical properties of Red Sea coastal waters should therefore be monitored regularly in order to minimize the formation of harmful algal blooms, which may affect all food web levels, including the human level.
A brief investigation of light minerals along the beaches between Valinokkam and Tuticorin has been carried out for the first time along the Southern Tamilnadu coast in order to discover the provenance of the sediments. The study spotlights a wide variation in light mineralogy along the three zones of the investigated area (Valinokkam, Vaippar and Tuticorin). A higher percentage of quartz is reported from the Valinokkam (48.34 to 68.63%) and Tuticorin zones (55.66 to 73.05%) than from the Vaippar zone (40.24 to 60.77%). The trend with regard to the maturity index is similar, with appreciably higher values in Valinokkam (1.15 to 1.89) and Tuticorin (1.61 to 1.94) than Vaippar (0.79 to 1.39). Morphological analysis of quartz grains shows a higher order of sphericity and roundness values in Valinokkam and Tuticorin as compared to Vaippar. Moreover, the surface texture of quartz grains observed with the aid of scanning electron microscope (SEM) photographs reveals the presence of different depositional environments and the multiple origin of beach sediments in the study area. From the present study of the light mineralogy of beach sediments, it is inferred that the source of the sediments is a mixed type: igneous and metamorphic crystalline rocks, together with palaeosediments.
On 26D ecember 2004, a tsunami severely affected almost all the coastal villages of Kanyakumari District, India. It was one of the worst affected coastal sectors of South India. An attempt has been made here to assess the impact of the tsunami hazard on coastal landforms and the level of inundation using GIS techniques. The areas of inundation were surveyed and mapped by fixing regular transects along the coastal regions. The percentage of inundated area in the total area was estimated. It was found that inundation was higher on low-lying coasts and relatively less on elevated coasts. In some cases, the extent of inundation was a few kilometres in relation to other coasts, but the percentage of inundated area in the total coastal area was high. The extent of inundation along the study area varied from 50 m to 450 m. Inundation was minimal in coastal villages like Kanyakumari, Agastheeswaram, Madhysoodhanapuram and Dharmapuram, but extensive at Colachel. The percentage of inundated area in the total area ranges from 8% (Dharmapuram) to 39% (Colachel). The degree of inundation was controlled by coastal geomorphological features such as sand dunes, cliffs, coastal vegetation, nature and configuration of the beach, not to mention the angle and velocity of the invading tsunami surge.
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