2 resultados para distribution of wealth

em AMS Tesi di Laurea - Alm@DL - Università di Bologna


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In this study we provide a baseline data on semidemersal fish assemblages and biology in a heterogeneous and yet less studied portion of the shelf of Antalya Gulf. The distribution of fish abundance in three transects subjected to different fisheries regulations (fishery vs non fishery areas), and including depths of 10, 25, 75, 125, 200 m, was studied between May 2014 and February 2015 in representative months of winter, spring, summer and autumn seasons. A total of 76 fish species belonging to 40 families was collected and semidemersal species distribution was analyzed in comparison with the whole community. Spatial distribution of fish was driven mainly by depth and two main assemblages were observed: shallow waters (10-25; 75 m) and deep waters (125-200 m). Significant differences among transects were found for the whole community but not for the semidemersal species. Analysis showed that this was due to a strong relation of these species with local environmental characteristics rather than to a different fishing pressure over transects. Firstly all species distribute according to the bathymetrical gradient and secondly to the bottom type structure. Semidemersal species were then found more related to zooplankton and suspended matter availability. The main morphological characteristics, sex and size distribution of the target semidemersal species Spicara smaris (Linnaeus, 1758), Saurida undosquamis (Richardson, 1848), Pagellus acarne (Risso, 1827) were also investigated.

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Nowadays we live in densely populated regions and this leads to many environmental issues. Among all pollutants that human activities originate, metals are relevant because they can be potentially toxic for most of living beings. We studied the fate of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn in a vineyard environment analysing samples of plant, wine and soil. Sites were chosen considering the type of wine produced, the type of cultivation (both organic and conventional agriculture) and the geographic location. We took vineyards that cultivate the same grape variety, the Trebbiano). We investigated 5 vineyards located in the Ravenna district (Italy): two on the Lamone Valley slopes, one in the area of river-bank deposits near Ravenna city, then a farm near Lugo and one near Bagnacavallo in interfluve regions. We carried out a very detailed characterization of soils in the sites, including the analysis of: pH, electric conductivity, texture, total carbonate and extimated content of dolomite, active carbonate, iron from ammonium oxalate, Iron Deficiency Chlorosis Index (IDCI), total nitrogen and organic carbon, available phosphorous, available potassium and Cation Exchange Capacity (CEC). Then we made the analysis of the bulk chemical composition and a DTPA extraction to determine the available fraction of elements in soils. All the sites have proper ground to cultivate, with already a good amount of nutrients, such as not needing strong fertilisations, but a vineyard on hills suffers from iron deficiency chlorosis due to the high level of active carbonate. We found some soils with much silica and little calcium oxide that confirm the marly sandstone substratum, while other soils have more calcium oxide and more aluminium oxide that confirm the argillaceous marlstone substratum. We found some critical situations, such as high concentrations of Chromium, especially in the farm near Lugo, and we noticed differences between organic vineyards and conventional ones: the conventional ones have a higher enrichment in soils of some metals (Copper and Zinc). Each metal accumulates differently in every single part of grapevines. We found differences between hill plants and lowland ones: behaviors of plants in metal accumulations seems to have patterns. Metals are more abundant in barks, then in leaves or sometimes in roots. Plants seem trying to remove excesses of metal storing them in bark. Two wines have excess of acetic acid and one conventional farm produces wine with content of Zinc over the Italian law limit. We already found evidence of high values relating them with uncontaminated environments, but more investigations are suggested to link those values to their anthropogenic supplies.