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1.
The issue of municipal solid waste (MSW) arisings has received great attention recently since it is not only a by-product of economic activity but also serves as an input to the economy through material or energy recovery. The main focus of this study is cultural formation and especially the current picture of waste culture and public perception across European Union (EU) member states. Thus, this study will first evaluate environmental efficiency with data envelopment analysis (DEA) based on five parameters: waste, gross domestic product (GDP), labour, capital, and population density for 22 EU Member States and for the years 2005, 2010 and 2015 in order to evaluate which Member States are more efficient. Then the efficiency results are contrasted to Hofstede’s and Schwartz’s cultural dimensions on STATA with the use of regression modelling. Results show that for year 2005 no significant relationship is noticed for both cultural models, whereas for years 2010 and 2015 there appears to be a significant connection. The above-mentioned findings can be associated with the financial crisis that has hit Europe after 2008 making people more sceptical, while EU legislations have laid out some important directives in the field of waste management. Finally, along with the factors above, EU has faced severe environmental challenges due to waste arisings, as well as accidents and injuries for people working in this sector, which in turn have widely modified EU’s waste culture as supported by this study’s results.  相似文献   

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Sorghastrum Nutans L. Nash is used as an adsorbent for the removal of Cr(VI) from wastewater. Adsorption coupled reduction i.e. indirect reduction is the mechanism of Cr(VI) removal by the biomaterial. The adsorbent surface became highly positively charged at lower pH, adsorption rate of Cr(VI) is faster and reduction reaction also accelerates at lower pH since the binding of negatively charged Cr(VI) ion species to the cationic groups is enhanced and protons take part in this reaction. The adsorbent is characterised by using XRD, FTIR, SEM and EDAX analysis. OH bending, CN stretching/bending and NH stretching play a major role in Chromium adsorption. Experimental values follow pseudo-second order reaction and Langmuir adsorption isotherm. Surface diffusion is the rate controlling mechanism for the process. The maximum percentage of Cr(VI) removal obtained is 75.5% with 7?g/L dosage at pH 1.3 and adsorbate concentration was 100?mg/L. From the normal probability, residual, contour, 3D surface, main effect and interaction plot along with t-test, ANOVA, and F-test, it is observed that pH has the most significant effect on the percentage removal followed by adsorbent dosage and time. The adsorbate concentration has the least effects and interaction effects are found to be significant.  相似文献   

4.
A polyvinylidene fluoride-based membrane bearing the diethylenetriaminepentaacetic acid chelating group was employed to recover Cu(II) from the Cu(II)-ethylenediaminetetraacetic acid complex aqueous solution. Effects of Ca(II), Fe(II), and Fe(III) on Cu(II) uptake were investigated by static batch adsorption tests and dynamic adsorption filtration. Isotherms, kinetics, and breakthrough curves of Cu(II) uptakes in the presence of the three cations at concentrations of 1 mmol L?1 were elucidated. The three cations showed a positive effect on the Cu(II) uptake; the stimulative roles were in the order of Fe(III) > Fe(II) > Ca(II). They did not alter the adsorption behavior of the membrane; adsorption isotherms and kinetics could be described by Langmuir and Lagergren second-order models, and Cu(II) adsorption was a spontaneous and exothermic process. The presence of Ca(II), Fe(II), and Fe(III) increased the sorption capacity of the membrane stack by 1.3, 1.9, and 3 times. Breakthrough time and the exhaustion time of membrane stacks were also extended.  相似文献   

5.
The purpose of this study is to experimentally determine the differences between four grazing treatments on the trampling of nests. Additionally, we examine to what extent the trampling probability of nests is higher close to a source of fresh water. We compare the trampling of artificial nests in five different grazing treatments in an experimental design. We use buried clay pigeon targets as artificial mimics of bird nests to obtain reliable estimates of trampling risk and compare these with real nests. We find that horses trample significantly more artificial nests than cattle resulting in lower survival rates of artificial nests under horse grazing than under cattle grazing. For both horses and cattle, we find a clear trend, approaching significance, towards more trampling at higher numbers of livestock. We found that more artificial nests are trampled closer to a freshwater tank. The survival probability of artificial nests in cattle grazed treatments in this study is found to be in the same range as real nests in the study area and very close to the survival probability of Northern Lapwing (Vanellus vanellus) nests under cattle grazing in a different system. We recommend that horses should not be used as grazers for management purposes in areas with high densities of birds’ nests in order to minimize the risk of nests being trampled. Additionally, we confirm that the location of freshwater tanks has an important effect on the distribution of livestock and hence on trampling of nests.  相似文献   

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Artemia franciscana was grown on Isochrysis galbana Green (clone T. Iso) at saturated food concentrations (13 to 20 mg C l−1) for 11 d at 26 to 28 °C, and 34 ppt salinity. Three groups of brine shrimp were used in the feeding experiments: metanauplius III and IV (Group 1), post-metanauplius II and III (Group 2) and post-metanauplius VIII (Group 3), corresponding to 4-, 7- and 11-d-old animals, respectively. The ingestion rate, clearance rate and carbon balance were estimated for these stages at different concentrations of 14C-labeled I. galbana ranging from 0.05 to 30 mg C l−1. The handling time of algae was determined for all three groups. The ingestion rate (I, ng C ind−1 h−1) increased as a function of animal size and food concentration. In all three groups, the ingestion rate increased to a maximum level (I max) and remained constant at food concentrations ≥10 mg C l−1 (saturated food concentrations). The clearance rate (CR, μl ind−1 h−1) increased with increasing food concentration up to a maximum rate (CR max), after which it decreased for even higher food concentrations. The functional response of A. franciscana was most consistent with Holling's Type 3 functional response curve (sigmoidal model), which for the two oldest groups (Group 2 and 3) differed significantly from a Type 2 response (p < 0.05). The gut passage time for the three groups of A. franciscana, feeding on saturated food concentration (20 mg C l−1), varied between 24 and 29 min. As the nauplii developed to pre-adult stage the handling time of the algae increased as a function of animal size. The assimilation rate (ng C ind−1 h−1) in the youngest stages (Group 1 and 2) increased with increasing food concentrations, reaching a maximum level close to 10 mg C l−1. At higher food concentrations the assimilation rate decreased, and the proportions of defecated carbon increased, reaching 60 to 68% in the post-metanauplius stages (Group 3). The assimilation efficiency (%) was high at the lowest food concentrations in all three groups (89 to 64%). At higher concentrations, the assimilation efficiency decreased, reaching 56 to 38% at the highest concentrations. Received: 2 February 2000 / Accepted: 25 March 2000  相似文献   

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Hybrid catalysts were synthesized by attaching iron(III)-tetrakis(p-hydroxyphenyl)porphyrin (FeTPP(OH)4) to humic acid (HA) via urea–formaldehyde polycondensation. FTIR spectra of the prepared catalysts indicated that the catalysts prepared via urea–formaldehyde polycondensation contained cross-links between the phenolic groups of FeTPP(OH)4 and HA, which contains aliphatic amine functional groups. The prepared catalysts were examined for their ability to catalyze the oxidative degradation of pentachlorophenol (PCP) in a contaminated soil suspension. The levels of PCP degradation and dechlorination for the hybrid catalysts were significantly higher than those for the non-modified catalyst, FeTPP(OH)4.  相似文献   

8.
Batch adsorption experiments were conducted to explore the adsorption of Cr(VI) in aqueous solutions by β-FeOOH-coated sand. We investigated the key factors which affected the adsorption process such as adsorbent dosage, initial pH, initial Cr(VI) ion concentration, contact time and temperature. The uptake of Cr(VI) was very rapid and 44.3%, 51.6%, 58.9% of the adsorption happened during the first 180 minutes at 293K, 303K and 313K, respectively. The pseudo-second-order rate equation successfully described the adsorption kinetics. To study the adsorption isotherm, two equilibrium models, the Langmuir and Freundlich isotherms, were adopted. At 293K, 303K and 313K, the adsorption capacities obtained from the Langmuir isotherm were 0.060, 0.070 and 0.076 mg Cr(VI) per gram of the adsorbent, respectively. Thermodynamic parameters such as the change of energy, enthalpy and entropy were calculated using the equilibrium constants. The negative value of ΔG0 and the positive value of ΔH0 showed that the adsorption of Cr(VI) in aqueous solutions by β-FeOOH-coated sand was spontaneous, endothermic and occurred by physisorption.  相似文献   

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The nettle caterpillar, Darna pallivitta (Moore) (Lepidoptera: Limacodidae), is an invasive pest with established populations on three Hawai’ian islands. Indigenous to Southeast Asia, D. pallivitta caterpillars cause defoliation of ornamental nursery stock and pose a human health hazard due to their urticating hairs that can cause painful skin reactions. Identification of the pheromone component n-butyl (E)-7,9-decadienoate (E7,9-10:COOnBu) from D. pallivitta has made it possible to investigate the phenology and population dynamics using baited traps. Male captures in Jackson traps baited with E7,9-10:COOnBu showed a vegetation preference for tall-grass fields and forest/grass interfaces over forest areas. Microlocation preferences were also found for trap height, with over 65% of males being caught in traps suspended at 1 m, compared with the traps at 3 and 5 m. Captures of male moths in traps baited with live females, and direct observations of female calling behavior, showed peak activities 6–7 h after the onset of scotophase. This is a much later communication period than for D. bradleyi and D. trima and may provide a mechanism by which D. pallivitta maintains reproductive isolation in areas where all three species are present. Coastal and inland transects established in eastern Hawai’i measured aspects of population fluctuations and radiation into new areas with relation to elevation and microclimate. Population expansion was measured by comparing moth population means and 80% population boundaries over time. Both population measures showed a higher expansion for the coastal transect. Differences in population expansion may be attributed in part to temperature and elevation, while precipitation does not seem to have a strong effect. Both the behavioral and ecological data collected can be used to optimize deployment of detection/control strategies and to predict population expansion/risk assessment for establishing quarantine protocols for the nettle caterpillar.  相似文献   

11.
The biomarker approach has been used for 25 years to study the environmental quality of marine, brackish and freshwater ecosystems. Biomarkers may indicate health status and can be applied to organisms of all zoological phyla by destructive or non destructive methods. For 5 years we have been using this approach in zooplankton to detect ecotoxicological alterations at low levels of the food chain due to contaminants. Here we review our approach to validate and apply biomarker techniques in zooplankton. We discuss advantages, limitations, some results and future research. We indicate that biomarkers in zooplankton can be used as new indices of trophic status and ecological integrity of Italian marine coastal and lagoon environments, to be included among the tools specified by Italian law D.Lgs. 152/2006.  相似文献   

12.
Environmental Geochemistry and Health - The contamination of bodies of water by potentially hazardous elements has in recent decades become an environmental problem that poses serious risks to...  相似文献   

13.
In Brazil, the main biofuel crop is sugarcane, and with its rapid expansion, there is much debate about what land uses and land covers it is replacing, and what are the associated environmental and social impacts. Some argue sugarcane is mainly replacing cattle pasture, thus having minimal impacts on native vegetation and small-scale family farming. In contrast, others claim sugarcane is replacing cropland traditionally under soybeans, rice, beans, and corn. Thus, food security is negatively affected and small-scale family farming livelihoods and culture are threatened. This is a proof-of-concept paper illustrating methods contributing toward the resolution of such debates. First we map land use and cover change in areas undergoing sugarcane expansion using satellite data from MODIS (Moderate Resolution Imaging Spectroradiometer); second, we test the hypothesis that sugarcane is replacing traditional annual crops using intensity analysis, via a case study of land change in the municipality of Pedro Afonso, Tocantins in northern Brazil between the 2008–2013 crop years. Maps matched reference data with overall agreements between 87–91%. Intensity analysis confirmed sugarcane is replacing annual crops much more than cattle pasture and other land uses and covers, pointing to particular economic and social processes driving land change.  相似文献   

14.
This study applied biomarkers and benthic indices at an area in North Evoikos Gulf, Greece, affected by metalliferous slag disposal. Biomarkers of antioxidant defense (catalase, glutathione S-transferase), and neurotoxicity (acetylcholinesterase) were measured in crabs Liocarcinus depurator. Iron (Fe), chromium (Cr), nickel (Ni), manganese (Mn), copper (Cu), and zinc (Zn) concentrations in sediments and crabs were also measured. High levels of all metals were found in sediments at the disposal area. Metal levels in the crabs were also higher in the disposal area although spatial differences were not as marked as in the sediments. Accordingly, biomarker responses of crabs in the disposal area were also noted suggesting impact on the antioxidant defense of the organisms against oxidative stress. Benthic indices showed disturbance in the disposal area. The combined approach of measuring biomarkers and contaminant levels in the crabs and sediment was complementary to the benthic indices approach providing indications of metal exposure related effects. Our results support the idea that a twofold monitoring approach of assessing both the benthic community structure shifts and the biomarkers and metal accumulation levels may integrate and capture both the structural and the toxicological effects of dumping onto the benthic communities.  相似文献   

15.
This paper explores challenges in reconciling the cultural, economic and ecological pillars of the sustainable development concept. It does so by examining how conflicts in the management of an island off the Irish coast called Skellig Michael, which has been internationally designated for its significant cultural and ecological attributes, have been intensified by: (a) increasing tourist numbers; (b) a re-framing of the site’s identity and (c) changing visitor motivations. These have resulted from the amplified attention the island has received following the release of Star Wars: The Force Awakens and The Last Jedi in which it features prominently. Following a critical identification and discussion of the fault lines between different stakeholders involved in the conservation and use of the island, the paper advances a roadmap for action to help resolve animosity in the governance of the site and facilitate its sustainable management in the context of changing visitor numbers and profiles.  相似文献   

16.
Hydrophobicity and bioaccumulation potential of linear and cyclic polydimethylsiloxane (PDMS) oligomers were estimated by reversed‐phase liquid chromatography and feeding experiments with guppies (Poecilia reticulata). PDMS concentrations in fish were determined by capillary column gas chromatography and gas chromatography‐mass spectrometry. In contrast to polychlorinated biphenyls (PCBs), only very small amounts of PDMS were retained by the fish after six weeks feeding.  相似文献   

17.
Eurythoe complanata (Pallas 1766) has been considered a cosmopolitan species with a great morphological similarity across its geographic range. To elucidate whether E. complanata is actually a single species, genetic (cytochrome oxidase subunit I and allozymes) and morphological differences were compared among specimens from the Pacific, Caribbean, and South Atlantic Oceans. Large levels of COI divergence (10–22%) and diagnostic allozyme loci identified three cryptic species: one in the eastern Pacific and two in the Atlantic, with one being morphologically differentiated and found only in islands. COI sequences between Pacific and Atlantic lineages were much more divergent than those of other transisthmian invertebrates, indicating their split before the Panama Isthmus closure or a faster evolutionary rate of COI for this species. The existence of two Atlantic species may be a consequence of parapatric speciation followed by a secondary invasion or even a sympatric speciation in the Atlantic oceanic islands.  相似文献   

18.
According to current theories of territoriality, an animal is expected to defend the smallest area that can provide resources for maximisation of reproduction, known as the economically defendable area. In group territorial species however, the strategies behind resource defence are likely to be more complex with corporate territoriality, cooperative breeding, delayed dispersal and intra-group competition all potentially playing a role. Here we examined group territoriality in a social herbivorous rodent, the Eurasian beaver Castor fiber. Beavers in our study do not inhabit economically defendable territories. Instead the sequence of arrival of pairs into unoccupied areas seems to play a more important role in determining the size of the territory, whereas group size is determined by past reproductive success. We argue that the settlement pattern and reproductive history have a lasting impact in the territorial system of beavers due to a combination of the low adult mortality, high dispersal costs, and avoidance of resource depletion.R.D. Campbell and F. Rosell contributed equally to this work  相似文献   

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The concept of sustainable development (SD) has highly been debated since it was presented 25 years ago, with ‘hard science’ approaches on one side and more process-oriented approaches on the other side. Academic teaching in SD has emerged in response to this in very different contexts, partly mirroring this academic debate. Some master’s programmes in SD take a strong science approach, while other programmes focus on the process of implementing sustainability projects, sometimes connected with forms of action research and teaching. In this article, we identify diverse views on the concept of SD as well as views on most relevant modes of teaching. We discuss core competencies required for sustainability professionals in their working practices and we organise them in three main clusters: Know, Interact and Be (KIB). The article presents the results of a worldwide survey, which addresses these visions on the concept of SD, the capabilities needed for ‘sustainable development professionals’ and the teaching approach needed. The analysis is based on the responses of 54 lecturers and 287 students active in 34 SD master’s programmes on all continents. The results of this worldwide survey are discussed. We observe in practice some gaps between preferences and practice. Looking at what both lecturers and students see as essential topics to address, some topics get relatively less attention (like the population issue). The identified core competencies (KIB) are supported and all addressed in practice, while the ‘Be’ competencies receive relatively less attention. Suggested consequences for academic teaching include a further matching of programmes with perceived needs and bridging the gap between the experienced teaching approaches in practice with such identified needs.  相似文献   

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