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981.
Kiran L. Dhanjal‐Adams Marcel Klaassen Sam Nicol Hugh P. Possingham Iadine Chadès Richard A. Fuller 《Conservation biology》2017,31(3):646-656
Conserving migratory species requires protecting connected habitat along the pathways they travel. Despite recent improvements in tracking animal movements, migratory connectivity remains poorly resolved at a population level for the vast majority of species, thus conservation prioritization is hampered. To address this data limitation, we developed a novel approach to spatial prioritization based on a model of potential connectivity derived from empirical data on species abundance and distance traveled between sites during migration. We applied the approach to migratory shorebirds of the East Asian‐Australasian Flyway. Conservation strategies that prioritized sites based on connectivity and abundance metrics together maintained larger populations of birds than strategies that prioritized sites based only on abundance metrics. The conservation value of a site therefore depended on both its capacity to support migratory animals and its position within the migratory pathway; the loss of crucial sites led to partial or total population collapse. We suggest that conservation approaches that prioritize sites supporting large populations of migrants should, where possible, also include data on the spatial arrangement of sites. 相似文献
982.
The planning and design of integrated municipal solid waste management (MSWM) systems requires accurate environmental impact evaluation of the systems and their components. This research assessed, quantified and compared the environmental impact of the first stage of the most used MSW container systems. The comparison was based on factors such as the volume of the containers, from small bins of 60–80 l to containers of 2400 l, and on the manufactured materials, steel and high-density polyethylene (HDPE). Also, some parameters such as frequency of collections, waste generation, filling percentage and waste container contents, were established to obtain comparable systems. The methodological framework of the analysis was the life cycle assessment (LCA), and the impact assessment method was based on CML 2 baseline 2000. Results indicated that, for the same volume, the collection systems that use HDPE waste containers had more of an impact than those using steel waste containers, in terms of abiotic depletion, global warming, ozone layer depletion, acidification, eutrophication, photochemical oxidation, human toxicity and terrestrial ecotoxicity. Besides, the collection systems using small HDPE bins (60 l or 80 l) had most impact while systems using big steel containers (2400 l) had less impact. Subsequent sensitivity analysis about the parameters established demonstrated that they could change the ultimate environmental impact of each waste container collection system, but that the comparative relationship between systems was similar. 相似文献
983.
Kajsa Borgnäs 《Environment, Development and Sustainability》2017,19(3):769-790
This paper is concerned with the normative underpinnings of popular sustainability indicators and country rankings. Attempts to quantify national sustainability in the form of composite indicators and rankings have increased rapidly over past decades. However, questions regarding validity and interpretability remain. This article combines theoretical and statistical tools to explore how input variables in five popular sustainability indicators can be related to different theoretical paradigms: weak and strong sustainability. It is shown that differences in theoretical interpretations affect input variable selection, which in turn affects indicator output. This points towards the risk of indicators becoming a sort of ‘circular argumentation construct’. The article argues that sustainability indicators and country rankings must be treated as theoretical just as much as statistical instruments. It is proposed that making underlying normative assumptions explicit, and making input variable selection more clear in a theoretical sense, can enhance indicator validity and usability for policy makers and researchers alike. 相似文献
984.
Monika Gąsecka Piotr Rzymski Marek Siwulski Sylwia Budzyńska Zuzanna Magdziak 《Journal of environmental science and health. Part. B》2017,52(3):171-177
ABSTRACTThe aim of this study was to determine the elemental composition, phenolic content and composition and antioxidant properties of Imleria badia (Fr.) Vizzini (former names Boletus badius (Fr.) Fr., and Xerocomus badius (Fr.) E.-J. Gilbert) fruiting bodies collected from sites with different levels of pollution. Imleria badia was relatively tolerant to soil contamination with toxic elements and was able to grow in As, Cd, Hg and Pb concentrations exceeding 15, 2.9, 0.4 and 77 mg kg?1, respectively. The concentration of elements in soil was reflected in the element content in I. badia. The fruiting bodies from polluted sites exhibited significantly higher content of all the analyzed elements. Among 21 individual phenolic compounds only protocatechiuc and caffeic acids, and quercetin were determined in fruiting bodies of I. badia. The differences between the concentration of the quantified phenolic compounds and the total flavonoid content in fruiting bodies of I. badia from unpolluted and polluted sites were not significant. However, the greatest total phenolic content was found in fruiting bodies from the polluted areas. The antioxidative capacity of mushrooms collected from heavily polluted sites was lower than those growing in unpolluted areas. The concentrations of some metals in soil and fruiting soil were positively correlated with phenolic content and IC50. 相似文献
985.
Clive A. Marks Malcolm Clark David Obendorf Graham P. Hall Inês Soares Filipe Pereira 《Conservation biology》2017,31(6):1450-1458
There has been little evaluation of anecdotal sightings as a means to confirm new incursions of invasive species. This paper explores the potential for equivocal information communicated by the media to account for patterns of anecdotal reports. In 2001, it was widely reported that red foxes (Vulpes vulpes) had been deliberately released in the island state of Tasmania (Australia), although this claim was later revealed to be baseless. Regardless, by 2013 a total of 3153 anecdotal fox sightings had been reported by members of the public, which implied their distribution was wide. For each month in 2001–2003, we defined a monthly media index (MMI) of fox‐related media coverage, an index of their relative seasonal abundance (abundance), and a factor denoting claims of fox evidence (claimed evidence) regardless of its evidentiary quality. We fitted a generalized linear model with Poisson error for monthly totals of anecdotal sightings with factors of year and claimed evidence and covariates of MMI, abundance, and hours of darkness. The collective effect of psychological factors (MMI, claimed evidence, and year) relative to biophysical factors (photoperiod and abundance) was highly significant (χ2 = 122.1, df = 6, p < 0.0001), whereas anticipated changes in abundance had no significant influence on reported sightings (p = 0.15). An annual index of fox media from 2001 to 2010 was strongly associated with the yearly tally of anecdotal sightings (p = 0.018). The odds ratio of sightings ranked as reliable by the fox eradication program in any year decreased exponentially at a rate of 0.00643 as the total number of sightings increased (p < 0.0001) and was indicative of an observer‐expectancy bias. Our results suggest anecdotal sightings are highly susceptible to cognitive biases and when used to qualify and quantify species presence can contribute to flawed risk assessments. 相似文献
986.
987.
Matías Salvo Andrés Lizasoain Matías Castells Viviana Bortagaray Sebastián Castro Rodney Colina Fernando Lopez Tort Matías Victoria 《Food and environmental virology》2018,10(2):193-200
Human bocavirus (HBoV) infections are related to respiratory and gastroenteric diseases. The aim of this study was to investigate the presence of HBoV in both sewage and surface waters in Uruguay. Sixty-eight sewage samples from the cities of Salto, Paysandú, Bella Unión, Fray Bentos, Treinta y Tres and Melo and 36 surface water samples from the cities of Salto, Florida and Santa Lucía were studied. HBoV was screened by multiplex qPCR for the detection of the four subtypes, followed by monoplex qPCRs for the independent quantification of each subtype. A qualitative PCR followed by DNA sequencing and phylogenetic analysis was carried out for molecular characterization of HBoV strains. HBoV was present in a high frequency (69%) in sewage and only one positive sample (3%) was found in surface water. Concerning sewage samples, HBoV1 was detected in 11 (23%) out of the 47 positives samples, with a mean concentration of 8.2 × 104 genomic copies/Liter (gc/L), HBoV3 was detected in 35 (74%) of the positive samples with a mean concentration of 4.1 × 106 gc/L and subtypes 2 and/or 4 were detected in 39 (83%) of the positive samples with a mean concentration of 7.8 × 106 gc/L. After the phylogenetic analysis performed by a Bayesian approach, the four HBoV subtypes were confirmed. This is the first study determining a high frequency of HBoV and the presence of the four HBoV subtypes in aquatic matrices in Latin America, mainly in sewage. Although HBoV was scarcely detected in surface water, a waterborne transmission is likely to occur if people enter in contact with polluted surface waters for recreational activities such as fishing or swimming since an elevated frequency of HBoV was detected in raw sewage which is usually directly discharged into surface waters. 相似文献
988.
Anderson Martins de Souza Braz Antonio Rodrigues Fernandes José Roberto Ferreira Luís Reynaldo Ferracciú Alleoni 《Environmental science and pollution research international》2013,20(10):7231-7242
The solid-solution distribution or partition coefficient (Kd) is a measure of affinity of potentially toxic elements (PTE) for soil colloids. Kd plays a key role in several models for defining PTE guideline values in soils and for assessing environmental risks, and its value depends on edaphic and climatic conditions of the sites where the soils occur. This study quantified Kd values for Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn from representative soil samples from Brazil’s eastern Amazon region, which measures 1.2 million km2. The Kd values obtained were lower than those set by both international and Brazilian environmental agencies and were correlated with the pH, Fe and Mn oxide content, and cationic exchange capacity of the soils. The following order of decreasing affinity was observed: Pb?>?Cu?>?Hg?>?Cr?>?Cd?≈?Co?>?Ni?>?Zn. 相似文献
989.
Xiaoning Yang Lushi Sun Jun Xiang Song Hu Sheng Su 《Waste management (New York, N.Y.)》2013,33(2):462-473
Plastics from waste electrical and electronic equipment (WEEE) have been an important environmental problem because these plastics commonly contain toxic halogenated flame retardants which may cause serious environmental pollution, especially the formation of carcinogenic substances polybrominated dibenzo dioxins/furans (PBDD/Fs), during treat process of these plastics. Pyrolysis has been proposed as a viable processing route for recycling the organic compounds in WEEE plastics into fuels and chemical feedstock. However, dehalogenation procedures are also necessary during treat process, because the oils collected in single pyrolysis process may contain numerous halogenated organic compounds, which would detrimentally impact the reuse of these pyrolysis oils. Currently, dehalogenation has become a significant topic in recycling of WEEE plastics by pyrolysis. In order to fulfill the better resource utilization of the WEEE plastics, the compositions, characteristics and dehalogenation methods during the pyrolysis recycling process of WEEE plastics were reviewed in this paper. Dehalogenation and the decomposition or pyrolysis of WEEE plastics can be carried out simultaneously or successively. It could be ‘dehalogenating prior to pyrolysing plastics’, ‘performing dehalogenation and pyrolysis at the same time’ or ‘pyrolysing plastics first then upgrading pyrolysis oils’. The first strategy essentially is the two-stage pyrolysis with the release of halogen hydrides at low pyrolysis temperature region which is separate from the decomposition of polymer matrixes, thus obtaining halogenated free oil products. The second strategy is the most common method. Zeolite or other type of catalyst can be used in the pyrolysis process for removing organohalogens. The third strategy separate pyrolysis and dehalogenation of WEEE plastics, which can, to some degree, avoid the problem of oil value decline due to the use of catalyst, but obviously, this strategy may increase the cost of whole recycling process. 相似文献
990.
S. Martínez-Lera J. Torrico J. Pallarés A. Gil 《Waste management (New York, N.Y.)》2013,33(7):1640-1647
The use of plastic bags and film packaging is very frequent in manifold sectors and film waste is usually present in different sources of municipal and industrial wastes. A significant part of it is not suitable for mechanical recycling but could be safely transformed into a valuable gas by means of thermal valorization. In this research, the gasification of film wastes has been experimentally investigated through experiments in a fluidized bed reactor of two reference polymers, polyethylene and polypropylene, and actual post-consumer film waste. After a complete experimental characterization of the three materials, several gasification experiments have been performed to analyze the influence of the fuel and of equivalence ratio on gas production and composition, on tar generation and on efficiency. The experiments prove that film waste and analogue polymer derived wastes can be successfully gasified in a fluidized bed reactor, yielding a gas with a higher heating value in a range from 3.6 to 5.6 MJ/m3 and cold gas efficiencies up to 60%. 相似文献