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231.
Atherina boyeri is a common inhabitant of the Mediterranean brackish and coastal waters. Several recent studies proposed the recognition of three distinct forms/species (one lagoon/freshwater and two marine) within an A. boyeri complex. In this study, we used 10 newly available microsatellite loci to better define the genetic structure of the lagoon form. A total of 428 fishes from 11 lagoons along the Italian and Albanian coasts and three Italian lakes were analyzed. A pronounced genetic spatial structure was confirmed for all considered geographic scales (near, medium and broad). A restricted gene flow was detected, suggesting reduced population connectivity. The comparison of present data and previous studies, based on mtDNA and RAPD markers, allowed a preliminary identification of the roles of recent factors (gene flow, habitat discontinuity and water currents) and past events (e.g., Pleistocene glaciations) in shaping the pattern of genetic differentiation.  相似文献   
232.
Aluminium is the most-used metal in the world after steel, with a wide range of applications in the industrial field owing to its physical and mechanical properties. The aim of this study was environmental and economic analysis of secondary aluminium. In particular, this study demonstrated that aluminium recycling offers many advantages to both consumers and industry:
  • Increased energy savings compared to primary aluminium production;

  • Recovery and reuse of raw materials for future production avoids consumption of non-renewable resources;

  • Reduction in landfill waste and consequent environmental damage;

  • Reduction in bauxite mining which, in turn, will reduce the socio-economic impact on populations of those countries, mainly underdeveloped, that contain mines;

  • Economic advantages for Italy, the first European producer of secondary aluminium, which lacks bauxite mines and has high energy costs.

This study used the Life Cycle Assessment (LCA) method, the modified Eco-indicator 99 method for damage calculation, and the SimaPro calculation code. The study examined secondary aluminium production by ICMET, based in Reggio Emilia, Italy. The economic and environmental evaluation utilised environmental information supplied by the company.  相似文献   
233.
We consider the concept of mutual information in ecological networks, and use this idea to analyse the Tangled Nature model of co-evolution. We show that this measure of correlation has two distinct behaviours depending on how we define the network in question: if we consider only the network of viable species this measure increases, whereas for the whole system it decreases. It is suggested that these are complimentary behaviours that show how ecosystems can become both more stable and better adapted.  相似文献   
234.
Lagrangian models of dispersion in marine environment   总被引:1,自引:0,他引:1  
Turbulent dispersion can be studied successfully by using Lagrangian particle models. In general, the prediction of correct concentration fields is a complex issue when the turbulent field is inhomogeneous and non-stationary. Two classes of Lagrangian dispersion models have been considered in this work, which are based on the Wiener process and the so called “well-mixed” criterion. In order to test the performances of these models and shed light on the underlying physical processes and modeling assumptions, four different numerical models have been compared and tested by means of their long time behavior by considering several study cases concerning idealized marine environment. Furthermore, the coupling of the community model Princeton Ocean Model (POM) with the Lagrangian model LASEMOD (LAgrangian SEa MODel) is used to investigate the temporal and spatial evolution of a passive pollutant released in the vicinity of the coast in the Tyrrhenian Sea basin. The simulation shows with reasonable accuracy the time evolution of both the hydrodynamic and the concentration fields and provides a useful insight into the evaluation of the environmental impact of pollutant releases along the coast.  相似文献   
235.
The implementation of an adaptive cluster sampling design often becomes logistically challenging because variation in the final sampling effort introduces uncertainty in survey planning. To overcome this drawback, an inexpensive and easy to measure auxiliary variable could be used in a two-phase survey strategy, called adaptive cluster double sampling (Félix-Medina and Thompson in Biometrika 91:877–891, 2004). In this paper, a two-phase sampling strategy is proposed which combines the idea of adaptive cluster double sampling with the principle of post-stratification. In the first-phase an adaptive cluster sample is selected by means of an inexpensive auxiliary variable. Networks from the first phase sampling are then post-stratified according to their size. In the second-phase, the network structure is used to select a subsample of units by means of stratified random sampling. The proposed sampling strategy employs stratification without requiring an a priori delineation of the strata. Indeed, the strata sizes are estimated in the course of the two-phase sampling process. Therefore, it is suitable for situations where stratification is suspected to be efficient but strata cannot be easily delineated in advance. In this framework, a new type of estimator for the population mean which mimics the stratified sampling mean estimator and an estimator of the sampling variance are proposed. The results of a simulation study confirm, as expected, that the use of post-stratification leads to gain in precision for the estimator. The proposed sampling strategy is applied for targeting an epiphytic lichen community Lobarion pulmonariae in a forest area of the Northern Apennines (N-Italy), characterized by several species of conservation concern.  相似文献   
236.
237.
Green public procurement (GPP) promises great potential for improving the environmental impact of many public organizations. However, the effects this instrument will have in the near future are unclear as there is little evidence on its exact level of engagement. This study thus aims to analyze the contents of tenders in terms of green criteria by specifically focusing on the building and construction sector. A total of 164 Italian public tenders were analyzed according to a protocol of analysis based on the GPP toolkit developed by the European Commission. Starting from a content analysis used in previous studies, a complete list of green criteria was developed in order to investigate their prevalence in the sample selected, with the aim of exploring their frequency, distribution and correlation. The results revealed a limited use of green criteria, which were mainly included as technical specifications and award criteria, thus shedding light on the difficulties that procurers are experiencing in the implementation of GPP practices. Several suggestions for policy makers and managers are identified for a better and faster implementation of green public procurement tools and methods.  相似文献   
238.
We respond to the paper of Kruse-Plass et al. (Environ Sci Eur 29:12, 2017), published in this journal, regarding the risk to non-target lepidopteran larvae exposed to pollen from one or more of three Bt maize events (MON810, Bt11 and 1507). We emphasise that what is important for environmental risk assessment is not the number of pollen grains per se, but the degree of exposure of a NT lepidopteran larva to Bt protein contained in maize pollen. The main text of this response deals with general issues which Kruse-Plass et al. have failed to understand; more detailed refutations of each of their claims are given in Additional file 1. Valid environmental risk assessment requires direct measurement of pollen on leaves at varying distances outside a source field(s); such measurements reflect the potential exposure experienced by an individual larva on a host plant. There are no new data in the Kruse-Plass et al. paper, or indeed any data directly quantifying pollen on actual host-plant leaves outside a maize field; only data gathered within or at the edge of maize crops were reported. Values quoted by Kruse-Plass et al. for deposition on host plants outside the field were estimates only. We reiterate the severe methodological criticisms made by EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016], which render this estimation procedure unreliable. Furthermore, criticisms of EFSA (EFSA J 2015(13):4127, 2015) and of EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016] made by Kruse-Plass et al. are shown in Additional file 1 to be without foundation. We therefore consider that there is no valid evidence presented by Kruse-Plass et al. to justify their conclusions.  相似文献   
239.
The present paper refers to the results of a research project on the polychlorinated dibenzyil-p-dioxin (PCDD) and polychlorinated dibenzofurans repartition in particulate and volatile phase in emissions from municipal solid waste incinerators. The distribution of such micropollutants between the different phases is analyzed in terms of absolute weights and in terms of 2, 3, 7, 8 TCDD Equivalents. This paper shows that more than half of the total content of PCDD/Fs emitted are adsorbed in the fly ash, with the remaining part in the volatile phase. Such repartition is inverted if the PCDD/Fs are expressed in terms of 2, 3, 7, 8 TCDD Equivalent.  相似文献   
240.
The aim of the study was to determine if an As-contaminated soil, stabilized using zerovalent iron (Fe0) and its combination with gypsum waste, coal fly ash, peat, or sewage sludge, could be used as a construction material at the top layer of the landfill cover. A reproduction of 2 m thick protection/vegetation layer of a landfill cover using a column setup was used to determine the ability of the amendments to reduce As solubility and stimulate soil functionality along the soil profile. Soil amendment with Fe0 was highly efficient in reducing As in soil porewater reaching 99 % reduction, but only at the soil surface. In the deeper soil layers (below 0.5 m), the Fe treatment had a reverse effect, As solubility increased dramatically exceeding that of the untreated soil or any other treatment by one to two orders of magnitude. A slight bioluminescence inhibition of Vibrio fischeri was detected in the Fe0 treatment. Soil amendment with iron and peat showed no toxicity to bacteria and was the most efficient in reducing dissolved As in soil porewater throughout the 2 m soil profile followed by iron and gypsum treatment, most likely resulting from a low soil density and a good air diffusion to the soil. The least suitable combination of soil amendments for As immobilization was a mixture of iron with coal fly ash. An increase in all measured enzyme activities was observed in all treatments, particularly those receiving organic matter. For As to be stable in soil, a combination of amendments that can keep the soil porous and ensure the air diffusion through the entire soil layer of the landfill cover is required.  相似文献   
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