During their upstream migration European glass-eels, Anguillu unguiflu (L.), encounter a series of varying environmental situations. The migration requires a sequence of physiological a d a p tations determined by the different chemico-physical conditions they meet. Temperature and salinity are two of the most important factors. It is reasonable that glass-eels may utilize them as cues to orientation. Laboratory experiments were designed to elucidate the thermal and salinity preferences of glass-eels. These were assessed by examining the choices of specimens caught either at sea and then kept in salt water (33%). or in the Arno river and then reared in fresh water. Water flows, triggering the rheotactic reaction, prompted glass-eels to choose between two different salinities and/or temperatures. The results confirm the preference of glass-eels for flows whose temperature does not differ from that of acclimation. Specimens tested towards two water flows, both at different temperatures from that of acclimation, preferred the colder. Fresh water was usually preferred to salt water, this preference being not so marked in the case of the glass-eels caught at sea and thus not yet adapted to fresh water. Clear-cut choices were recorded when one of the tested flows presented both the preferred temperature and preferred salinity. When only one of the two parameters reproduced the preferred situation, the choices were differently affected by temperature and salinity at different values of temperature. When the temperature of both flows was below 1 1-12" C. glass-eels preferred fresh water; at higher temperatures the colder of the two flows was preferred, even if salty.
The presence of potentially toxic elements (PTEs) may hinder a more widespread application of biosolids in agriculture. At present, the European Directive 86/278/CEE limit the total concentrations of seven metals (Cu, Cr, Ni, Pb, Zn, Cd and Hg) in agricultural soils and in sewage sludges used as fertilizers but it has not taken into consideration the potential impacts of other emerging micropollutants that may be present in the biosolids as well as their mobility. The aim of this study was to evaluate the accumulation and mobility of 13 elements (including regulated metals and other inorganic species) in agricultural soils repeatedly amended with biosolids for 15 years. Firstly, three digestions programs using different acid mixtures were tested to evaluate the most accurate and efficient method for analysis of soil and sludge. Results demonstrated that sewage sludge application increased concentrations of Pb and Hg in soil, but values did not exceed the quality standard established by legislation. In addition, other elements (As, Co, Sb, Ag, Se and Mn) that at present are not regulated by the Spanish and European directives were identified in the sewage sludge, and significant differences were found between Ag content in soils amended with biosolids in comparison with control soils. This fact can be related to the increasing use of silver nanoparticles in consumer products due to their antibacterial properties. Results from the leaching tests show up that, in general, the mobility degree for both regulated and non-regulated elements in soils amended with biosolids was quite low (<10 %).
Reduction of energy consumption in educational buildings, and primarily in University buildings, is nowadays a relevant issue. The evaluation of the energy performance of these buildings is complex due to the variability in their construction age and their intermittent and wide variety of uses. In addition, these buildings are often characterized by a scarce availability of energy end use data, which makes challenging to benchmark energy performance and to inform energy policy decisions. To tackle this problem, this paper explores the use of simple indicators linking low-frequency available energy consumption data to variables measuring building characteristics and weather conditions. The use of such indicators is accompanied by detailed ad-hoc energy audits, including activities in the area of building management systems and dynamic energy simulation. The case study chosen is the Italian University of Modena and Reggio Emilia, which recently developed a Sustainability Plan targeting reductions in GHG emissions to 2020 and identified a framework for investment over the next 5 years to meet University targets. The results of the study shows that simple performance indicators can provide a first insight into the buildings energy performance and identify critical buildings that require detailed analysis. The results of the energy audits support the decision of actions to reduce heating and cooling energy consumption while maintaining acceptable thermal comfort for occupants.
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