Search results for "Shore"
showing 10 items of 263 documents
Hydrologic and geochemical survey of the lake ‘‘Specchio di Venere’’ (Pantelleria island, Southern Italy)
2007
Hydrological and geochemical studies performed on Lake Specchio di Venere on Pantelleria island (Italy) indicate that this endorheic basin has been formed through upwelling of the water table, and that it is continuously fed by the thermal springs situated on its shores. The lake is periodically stratified both thermally and in salinity, albeit this stratification is rather unstable over time, since meteorological events such as strong rain or wind can determine the mixing of its waters. Periodical analyses of the lake water chemistry show large variations of the salt content due to the yearly evaporation-rain dilution cycle. These processes are also responsible for the saline stratificatio…
Recent benthic foraminiferal assemblages and their relationship to environmental variables on the shoreface and inner shelf off Valencia (Western Med…
2014
The environmental variables that determine the distributions of benthic foraminiferal assemblages on the shoreface and inner shelf of the north of Valencia province (Western Mediterranean) are identified. The possible influence of variables such as water depth, distance from shore, hydrodynamics, substrate type, carbonate content, organic matter content and human activity is evaluated. Multivariate cluster-Q-type analysis and redundancy analysis (RDA) are used to identify the environmental variables that have the greatest influence on the assemblage distribution. The spatial distribution of the assemblages is closely associated with water depth and substrate. The diversity and abundance of …
The Geologic History of the Marginal Basins Along the North Shore of the Gulf of Guinea
1973
The North shore of the Gulf of Guinea forms the coastline of Liberia, the Ivory Coast, Ghana, Togo, Dahomey, Nigeria, and the Cameroons (Fig. 1). The westernmost point of the coastal region to be discussed here is Cape Palmas (long 8° W) on the border between Liberia and the Ivory Coast. The easternmost limit is formed by the Cameroons Bight at long 9° 30′ E. The marginal basins are limited to the north by the upper Guinea arch which stretches for more than 2000 km in a west-east direction from Liberia to the Cameroons. In this arch region the metamorphic basement is exposed over wide areas. Some of the details of this basement are discussed by Hurley and Rand, and by Grant in this book. Fo…
Komunitas Gastropoda pada Padang Lamun Perairan Pantai Manokwari
2021
Penelitian ini bertujuan mengidentifikasi dan menganalisa struktur komunitas gastropoda di pesisir pantai Manokwari. Pengambilan sampel menggunakan metode transek di dua stasiun pengamatan yaitu Pantai Briosi BLK dan Pantai Rendani. Setiap stasiun diletakkan tiga garis transek ke arah laut dan setiap transek terdiri atas 10 kuadrat. Transek ini diletakkan di atas padang lamun. Analisis data dilakukan meliputi indeks keanekaragaman, indeks keseragaman, dominasi dan kepadatan gastropoda. Hasil penelitian menunjukkan ditemukan bahwa kualitas perairan di kedua lokasi sampling dapat mendukung pertumbuhan gastropoda. Komposisi spesies gastropoda yang ditemukan pada kedua lokasi sampling meliputi …
A geophysical and geochemical approach for seawater intrusion assessment in the Acquedolci coastal aquifer (Northern Sicily)
2007
Vertical electrical sounding (VES’) surveys and chemical analyses of groundwater have been executed in the coastal plain of Acquedolci (Northern Sicily), with the aim to circumscribe seawater intrusion phenomena. This urbanized area is representative of a more general problem interesting most of Mediterranean littoral areas, where intensive overdraft favors a heavy seawater intrusion through the coastline. Aquifer resistivity seems decisively to be conditioned by the chlorine and magnesium content in the main aquifer of the region. Schlumberger VES’, together with piezometric and chemical–physical information of groundwater, allowed us to perform hydrogeological and geophysical elaborations…
Comparison of sampling methods and habitat types for detecting impacts on lake littoral macroinvertebrate assemblages along a gradient of human distu…
2010
We explored environmental variables structuring littoral macroinvertebrate communities in a large lake basin along a gradient of nutrient enrichment. Furthermore, we evaluated sensitivity and cost-effi ciency of different sampling schemes (i.e. combinations of three habitat types and a number of standard sampling methods) to detect changes in macroinvertebrate communities along this anthropogenic disturbance gradient. Partial canonical ordination analysis showed that habitat characteristics accounted for a major part (56 % uniquely) of the explained variation in the species composition of invertebrate communities. When different mesohabitats were examined separately, assemblage variation of…
Vertical distribution of two sympatric labrid fishes in the Western Mediterranean and Eastern Atlantic rocky subtidal: local shore topography does ma…
2011
Changes in the shore topography (e.g. slope) occur at a scale of hundreds of meters in several locations in the Lusitanian and the Mediterranean Sea provinces. We tested whether differences in the bottom inclination might affect the vertical distribution patterns of two sympatric coastal labrid fishes, the rainbow wrasse Coris julis and the ornate wrasse Thalassoma pavo. Visual censuses were used to determine the distribution and abundance of these labrid species in high (‡30� ) and low (£3� ) slope rocky substrates covered by brown macroalgae and at two different depths (shallow, 4‐7 m, and deep 14‐20 m). Pectoral fin aspect ratio was used as an estimate of swimming performance to potentia…
Shortage of Sediments in the Maspalomas Dune Field (Gran Canaria, Canary Islands) Deduced from Analysis of Aerial Photographs, Foraminiferal Content,…
2007
Abstract The Maspalomas dune field and adjacent beaches are the most extensive coastal sedimentary environment on the island of Gran Canaria. This area is very important from both a natural and an economic perspective. The analysis of aerial photographs and satellite images from recent decades does not show important shoreline changes for the El Ingles and Maspalomas beaches, which can be considered, consequently, in a state of equilibrium. However, the Maspalomas dune field presents several modifications, such as aeolian corridors associated with beach kiosks, a significant reduction in thickness of the aeolian deposits, and an increase of deflation areas in the underlying substratum. All …
New solutions for energy supply: sea wave and offshore photovoltaic in Sardinia (Italy)
2018
This work illustrates a study on the integration among sea wave farm and off shore photovoltaic in Italian island (Sardinia). In order to exploit both energy sources, the paper presents an innovative prototype, designed and developed by Palermo University. According the data about sea wave and solar energy potential, we evaluated the installation of wave-solar energy farms, based on the prototype presented in this paper.
Surface sediment dynamics along the Tunisian coast at Skhira (Gulf of Gabès, south-eastern Tunisia)
2015
Abstract An investigation was conducted in the summer of 2012 at 24 study stations along the Tunisian coast near Skhira (south-eastern Mediterranean Sea) through high resolution of analyses, grain size and mineral composition of surface sediment. An Acoustic Doppler Current Profiler showed Skhira's main coastal current to follow a direction 60°E, with its main axis south-west/north-east parallel to the coastline and its minor axis east-west. Current speeds were approximately 13 cm s−1 and 4.5 cm s−1 for the major and minor axes, respectively. Parallel to the coast, currents were generally mild to moderate, but often exceeded 20 cm s−1. An Argonaut meter recorded the dominant current directi…