Search results for "feature"
showing 10 items of 4091 documents
Political and economic fisheries management in the Channel of Sicily
2006
Fishery activities in the Mediterranean Sea are characterized by a number of distinctive features which include relative extension of national to international waters, straddling and shared stocks, overall characteristics of fishing activities, availability of scientific information and the absence of a policy fisheries management in many coastal States. Therefore, the principal objective of this paper is to portray a framework on the politics of management of the fish resources in the Channel of Sicily, by examining both the CFP in the Mediterranean or the Italian–Tunisian relationship, and then to inspect the fishing effort of the Sicilians and Tunisian productive structures to carry out …
Soil aggregate stability under different Mediterranean vegetation types
1998
The influence of vegetation type on soil erodibility was studied by means of aggregate stability measurements using the Modified Emerson Water Dispersion Test (MEWDT), water-drop impacts (CND and TDI) and Ultrasonic Disruption (UD) methods on soils from north-facing slopes of the mountain range of La Serra Grossa in the eastern Iberian Peninsula. Soils with similar characteristics but covered by the main plant species at the study area were selected. Quercus ilex woodland showed the most resistant soil aggregates followed by Q. coccifera and Pistacea lentiscus scrubland, Brachypodium retusum grassland and Pinus halepensis woodland. Aggregates developed beneath dwarf shrubs like Rosmarinus o…
Study And Monitoring Of Salt Water Intrusion In The Coastal Area Between Mazara Del Vallo And Marsala (South-Western Sicily)
2007
In this chapter the study of a coastal aquifer located in South-Western Sicily (between the towns of Marsala and Mazara del Vallo) is presented, carried out using geochemical, hydro-geological and geophysical techniques. The aquifer has been over-exploited to the point of being subject to intense and worrisome salt-water intrusion. A preliminary chemical and physical characterization of the waters was carried out; this included measuring their conductivity and their chloride content. This allowed to detect the marine intrusion wedge in the coastal aquifer. A series of electromagnetic soundings, suitably calibrated by well logs, were effected in the whole area and allowed to create a 3D inte…
Insular variation in central MediterraneanCrociduraWagler, 1832 (Mammalia, Soricidae)
1990
Morphometric variation of Crocidura mandible in Sicily and surrounding islands (Egadi archipelago, Ustica, Pantelleria and Gozo) was analyzed by principal component and canonical variate analyses in order to integrate recent chromosomal and biochemical observations. Specimens of C. suaveolens and C. leucodon from mainland Italy and of C. russula from Sardinia were used as reference in this analysis. The biometry of the only taxon of shrews living in Sicily is significantly different from the three reference samples. This result, coupled with a recently discovered new karyotype, provides strong evidence for a new Eurasian species, for which the name C. sicula Miller 1901, was chosen. Crocidu…
New records of marine Tardigrada in the Mediterranean Sea
1996
Abstract Meiofauna from Chafarinas archipelago (western Mediterranean, N. Africa) were studied, and marine Tardigrada were identified to species level. A total of 15 species, belonging to families Stygarctidae, Halechiniscidae (Subfamilies Halechiniscinae, Florarctinae, Styraconyxinae and Tanarctinae), Batillipedidae, and Echiniscoididae, were found for the first time from the Alboran Sea and southwestern Mediterranean area. Four species and one subspecies are new records for the Mediterranean Sea: Floractus acer , F. asper , F. stellatus , Actinarctus doryphorus and Echiniscoides sigismundi hispaniensis . The male of Floractus stellatus , previously unknown to science, is described. Many s…
Short-term variability of mesozooplankton in a Mediterranean Coastal sound (Stagnone di Marsala, Western Sicily)
2001
Short-term variations in mesozooplankton were studied during four 24-h periods at one station in a Mediterranean coastal sound (Stagnone di Marsala, western Sicily) in May, July and October 1996 and March 1997. Zooplankton samples were collected every three or six hours with a plankton net (mesh size 125 µm) towed horizontally at the surface. Hydrometric data (height of tide, speed and direction of current) were also recorded to assess the influence of the hydrodynamic conditions on fluctuations in zooplankton abundance and changes in population structure. The zooplankton assemblages were markedly dominated by copepods and their naupliar stages, which consistently accounted for more than 95…
Drought Management Decision Support System by Means of Risk Analysis Models
2007
Droughts in arid and semiarid Mediterranean river basins have an increasing socioeconomic and environmental impact. The problem is especially complex in basins where droughts are very frequent and intense and where water resources are under a massive use. For that reason in the Mediterranean basins it is necessary to manage the water resources in constant alert in order to relieve the consequences of a drought. In this chapter a complete methodology for the mitigation of the droughts is defined. The methodology includes different tools: from the definition of an alert system for the different types of drought up to the simulation and optimization software for water system management. This m…
Four-year soil erosion rates in a running-mountain trail in eastern Iberian Peninsula
2019
During the last decades, the use of mountain trails for running is more and more popular. New trails are opened to allow the runners to practice and compete. This form of human impact on the landscape is new as the new trails do not follow the conservation strategies in design and maintenance as traditional mountain trails constructed by farmers, shepherds and muleteers do. This impact of sport events in nature is not measured and we know little about this impact on vegetation, fauna and soils. We surveyed in September 2018 a trail that was opened in September 2014 and was used for four official mountain trail races, and for training by local runners. Our interviews with organizers and user…
Comparing different methods to determine soil physical quality in a mediterranean forest and pasture land
2016
Soil physical quality (SPQ) can be assessed by different experimental methodologies and criteria and the optimal/critical values or ranges for SPQ indicators are still approximate. Sampling soils with minimal anthropic pressures should allow improvements in SPQ assessment. Different experimental methodologies and criteria were applied to sample a Mediterranean oak forest (Quercus ilex L.) and pasture land, in Sicily, with a varying degree of anthropic disturbance. Soil water retention was determined in the laboratory and the field, using the BEST (Beerkan Estimation of Soil Transfer parameters) procedure of soil hydraulic characterization. Capacity-based indicators, the S index, and locatio…
Loss of Ostracoda biodiversity in Western Mediterranean wetlands
2008
1. The coastal area of Valencia (Spain) in the Western Mediterranean is rich in freshwater and brackish wetlands. These areas are mostly protected for bird conservation but are also highly affected by human impacts. Six shallow lakes located in Ramsar wetland sites of this area were studied in order to assess past and present ostracod biodiversity and relate it to the status of the lakes, taking into consideration the indicator value of these easily fossilizable crustaceans. 2. In all the wetlands studied, ostracod taphocoenoses showed much higher species richness than the corresponding biocoenoses. This is expected from the time accumulative character of the taphocoenosis, but the trend is…