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1.
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Background

In the years 2000 and 2002, the German Environment Agency in Berlin (UBA) published the results of a comprehensive LCA study on beverage containers comprising aluminium cans with volumes of 330 ml and 500 ml. Starting with the aluminium can scenarios and the respective results obtained during the UBA study, additional analyses were performed by IFEU in 2003, a German consultant having been a member of the project team working on the UBA study. The objective was to examine the influence of selected parameters on the LCA profile of carbonated soft drink containers. Data and method were in complete analogy with the LCI and LCA part of the UBA study.

Materials

In 2006, the aluminium industry commissioned a study on further influential factors that help determine the sale of certain types of beer, studying the effects of two selected parameter settings on the comparative results of the aluminium can against the refillable glass bottle. In this scenario, special attention was given to two influential factors, the distribution distance—distinguished by regional and nationwide distribution—and trippage rate.

Results and discussion

The results of the initial LCA from the years 2000 and 2002 showed, for the examined parameters container weight, rate of post-consumer recovery of used containers, degree of recycled content and quality of the recycling routes, that each had a considerable influence on the environmental impact profile of the aluminium can within the given framework. Can weight and recycling rate were sensitive factors in the impact categories of climate change, fossil resources, summer smog (POCP), acidification and terrestrial eutrophication. Can volume affected virtually all impact categories examined.

Conclusions

By now, individual improvement options have already been put into practice in Germany. The environmental profile of the average 330 ml aluminium can on the German market can be expected to be ahead of that of the aluminium can at the time of the UBA study. The introduction of a 500-ml can on the market denotes a fundamental step forward in improving LCA results of the aluminium can as a container for beverages.
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3.

Background, aim, and scope

The rise in wood fuel consumption, particularly of charcoal, has been associated with increased deforestation in Ghana. Plantation developments from teak (Tectona grandis), bamboo (Bambusa balcooa), and Acacia auriculiformis are now being promoted to produce sustainable biomass for charcoal production. While all species have comparable charcoal quality, there is limited available data to elucidate the environmental impacts associated with their plantation development and use as biomass sources for producing charcoal. Therefore, this study quantified and compared the cradle-to-gate environmental impacts of producing charcoal from T. grandis, A. auriculiformis, and B. balcooa.

Methods

The study was conducted in accordance with ISO 14040/14044, an international procedural framework for performing life cycle analysis (LCA). For this study, the functional unit of charcoal used was 1 MJ energy produced from three species: T. grandis, A. auriculiformis, and B. balcooa. Data on B. balcooa plantations was collected from a B. balcooa-based intercropping system set up by the International Network for Bamboo and Rattan in Sekyere Central District, Ghana. Input data for A. auriculiformis and T. grandis came from the Forestry Commission of Ghana plantations established within the forest agroecological zone of Ghana. All input data came from primary local sources. Pollutant emissions were also calculated in order to analyze the contribution of all the flow processes to the emissions. The analysis used Simapro version 8, as well as life cycle inventory (LCI) databases of Ecoinvent V3 and Idemat 2015 (a database developed by Delft University of Technology, the Netherlands). The emissions were expressed as eco-costs and used as indicators in an impact assessment.

Results and discussion

The results showed that relative to B. balcooa, the total eco-cost (comprising of human health, ecosystem, resource depletion, and global warming eco-costs) of a cradle-to-gate production of 1 MJ of charcoal will be 140% higher with T. grandis and 113% higher with A. auriculiformis. The increased environmental impacts associated with T. grandis and A. auriculiformis occurred at their biomass production stage. As these species use comparatively large quantities of pesticides, weedicides, and fertilizers with high acidification, ozone depletion, and global warming potentials, their biomass production stage accounted for approximately 85% of their total eco-cost.

Conclusions

The study results suggest that B. balcooa plantations are the most environmentally viable option. In cases where T. grandis or A. auriculiformis plantations are widespread, improvement options at the biomass production stage are required in order to reduce their environmental costs.
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V. cholerae, V. parahaemolyticus, and V. vulnificus are recognized human pathogens. Although several studies are available worldwide, both on environmental and clinical contexts, little is known about the ecology of these vibrios in African coastal waters. In this study, their co-occurrence and relationships to key environmental constraints in the coastal waters of Guinea-Bissau were examined using the most probable number-polymerase chain reaction (MPN-PCR) approach. All Vibrio species were universally detected showing higher concentrations by the end of the wet season. The abundance of V. cholerae (ISR 16S-23S rRNA) ranged 0–1.2 × 104 MPN/L, whereas V. parahaemolyticus (toxR) varied from 47.9 to 1.2 × 105 MPN/L. Although the presence of genotypes associated with virulence was found in environmental V. cholerae isolates, ctxA+ V. cholerae was detected, by MPN-PCR, only on two occasions. Enteropathogenic (tdh+ and trh+) V. parahaemolyticus were detected at concentrations up to 1.2 × 103 MPN/L. V. vulnificus (vvhA) was detected simultaneously in all surveyed sites only at the end of the wet season, with maximum concentrations of 1.2 × 105 MPN/L. Our results suggest that sea surface water temperature and salinity were the major environmental controls to all Vibrio species. This study represents the first detection and quantification of co-occurring Vibrio species in West African coastal waters, highlighting the potential health risk associated with the persistence of human pathogenic Vibrio species.  相似文献   

6.
With an objective to optimize an approach to transfer value-added genes to a wheat variety while maintaining and improving agronomic performance, two alleles (Als1 and Als2) with mutations in the acetolactate synthase (ALS) gene located on the long arm of wheat chromosomes 6B and 6D providing tolerance to imazamox herbicide were transferred to Eltan, a popular soft white common winter wheat cultivar in the Pacific Northwest (PNW), USA. Four-step marker-assisted background selection and marker assisted forward breeding approaches were used to develop a wheat variety carrying two genes (Als1 and Als2) for imazamox tolerance along with improvements in many other agronomic traits. Screening of 1600 BC1 plants for imazamox tolerance identified 378 plants that were further screened with markers to identify seven plants that were used to make a population of 1400 BC2 plants, and the selection cycle was repeated. Progeny of 17 selected BC2F1 plants was evaluated for various agronomic and quality parameters to select 12 plants that were increased for field testing. Field evaluation of these lines conducted over 58 location-years along with evaluation in the greenhouse/growth chamber led to the selection of a line “WA8143” carrying the two genes for imazamox tolerance that yielded >3% higher than Eltan did. With 96.8% similarity to the recurrent parent, WA8143 also showed a better disease resistance package and grain quality needed in a successful Pacific Northwest wheat variety and was subsequently released for cultivation under the name of “Curiosity CL+.”  相似文献   

7.
Semi-sessile Mytilus mussels are used as indicators of climate changes, but their geographic distribution is not sufficiently known in the Arctic. The aim of this study was to investigate the taxonomic status and genetic differentiation of Mytilus populations in a Northwest Greenlandic fjord at Maarmorilik, impacted by contaminations from a former mine. In this study, mussels were collected at three sites differing in exposure to environmental factors. A total of 54 polymorphic SNPs found in the Mytilus EST and DNA sequences analyzed were successfully applied to 256 individuals. The results provided the first evidence for the existence of M. trossulus in Greenland. The mussel from M. trossulus and M. edulis taxa are shown to coexist and hybridize in the fjord. The three studied sites were found to differ significantly in the distribution of taxa with a higher prevalence of M. trossulus in the inner fjord. The identified M. edulis × M. trossulus hybrids mostly had a hybrid index score of about 0.5, indicating a similar number of alleles characteristic for M. trossulus and M. edulis. There was a low number of backcrosses between ‘pure’ taxa and hybrids. This newly discovered hybrid zone between the two taxa is unique in comparison with the Canadian populations. As Mytilus mussels in Greenland hitherto have been regarded as the one taxon M. edulis, the results have importance for biogeography and future monitoring and environmental studies.  相似文献   

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Although reef corals are dependent of the dinoflagellate Symbiodinium, the large majority of corals spawn gametes that do not contain their vital symbiont. This suggests the existence of a pool of Symbiodinium in the environment, of which surprisingly little is known. Reefs around Curaçao (Caribbean) were sampled for free-living Symbiodinium at three time periods (summer 2009, summer 2010, and winter 2010) to characterize different habitats (water column, coral rubble, sediment, the macroalgae Halimeda spp., Dictyota spp., and Lobophora variegata, and the seagrass Thalassia testudinum) that could serve as environmental sources of symbionts for corals. We detected the common clades of Symbiodinium that engage in symbiosis with Caribbean coral hosts A, B, and C using Symbiodinium-specific primers of the hypervariable region of the chloroplast 23S ribosomal DNA gene. We also discovered clade G and, for the first time in the Caribbean, the presence of free-living Symbiodinium clades F and H. Additionally, this study expands the habitat range of free-living Symbiodinium as environmental Symbiodinium was detected in T. testudinum seagrass beds. The patterns of association between free-living Symbiodinium types and habitats were shown to be complex. An interesting, strong association was seen between some clade A sequence types and sediment, suggesting that sediment could be a niche where clade A radiated from a free-living ancestor. Other interesting relationships were seen between sequence types of Symbiodinium clade C with Halimeda spp. and clades B and F with T. testudinium. These relationships highlight the importance of some macroalgae and seagrasses in hosting free-living Symbiodinium. Finally, studies spanning beyond a 1-yr cycle are needed to further expand on our results in order to better understand the variation of Symbiodinium in the environment through time. All together, results presented here showed that the great diversity of free-living Symbiodinium has a dynamic distribution across habitats and time.  相似文献   

10.

Purpose

Life cycle assessment (LCA) is commonly presented as a tool for rational decision-making. It has been increasingly used to support decision-making in situations where multiple actors possess diverse, and sometimes conflicting, perspectives, values and motives. Yet, little effort has been placed on understanding LCA in a social framework of action. This paper aims to analyse the legitimacy of LCA in public sector decision-making situations, the criticisms presented against LCA, and suggest potential ways to alleviate these criticisms.

Methods

This study consists of a case study of the application of LCA in the waste management sector in England and France. To gain an understanding of the justification and criticism of LCA, semi-structured interviews were undertaken with national and local level waste management actors. The justifications and criticism of the application of LCA was analysed through an analytical framework, the economies of worth. This suggests that in situations of disagreement, actors’ justifications are required to show their attachment to plural forms of common good. This work analyses the orders of worth in which justifications and criticisms of the application of LCA were based.

Results and discussion

LCA is applied primarily as a test of environmental efficiency, illustrating a collaboration between the industrial and green orders of worth. Actors apply LCA with the aspiration of replicating the scientific method and producing robust evidence to support the most efficient waste treatment option. In this case, efficiency is coupled with the green order of worth, where gains in efficiency mean lower environmental impacts. Internal criticisms of LCA, based in the industrial order of worth, highlights the limitations of LCA to act as a test of environmental efficiency. Furthermore, criticism based in the civic order of worth highlights the friction which arises in decision-making situations when LCA has been seen to subjugate the civic nature of waste management decisions.

Conclusions

One potential way forward for LCA may be to introduce aspects relevant in the civic order of worth which aims at achieving a compromise between the industrial and civic orders of worth. Envisioning LCA as a process-oriented tool, as opposed to an outcome-oriented tool, can allow for aspects on public involvement in the LCA process, thereby increasing its civic legitimacy.
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11.
This study was conducted to determine the environmental factors affecting the level of potentially toxic Microcystis. The long-term tendencies of temperature, precipitation, and water quality factors were analyzed to determine the environmental characteristics of the Daechung Reservoir in Korea, and water samples were directly collected to analyze the dynamics of toxic and non-toxic Microcystis at weekly intervals from May to October 2012. Microcystis was the dominant genus during the study period, and it was composed of potentially toxic and non-toxic Microcystis. The fraction of potentially toxic Microcystis ranged from 6.0% to 61.1%. The amount of toxic Microcystis was highly related to the intracellular microcystin concentration (r = 0.760, P < 0.01). Therefore, the fraction of potentially toxic Microcystis is an important concern in Microcystis blooming because the intracellular microcystin concentration may reflect microcystin levels in the water. The prevalence of potentially toxic Microcystis was highly related to water temperature in Daechung Reservoir (r = 0.585, P < 0.01). Thus, temperature increase during Microcystis blooming may lead to more frequent toxic Microcystis blooms in eutrophic water bodies.  相似文献   

12.
Candida albicans is the most common human fungal pathogen and can grow as yeast or filaments, depending on the environmental conditions. The filamentous form is of particular interest because it can play a direct role in adherence and pathogenicity. Therefore, the purpose of this study was to evaluate the effects of three clinical strains of Lactobacillus on C. albicans filamentation as well as their probiotic potential in pathogen-host interactions via an experimental candidiasis model study in Galleria mellonella. We used the reference strain Candida albicans ATCC 18804 and three clinical strains of Lactobacillus: L. rhamnosus strain 5.2, L. paracasei strain 20.3, and L. fermentum strain 20.4. First, the capacity of C. albicans to form hyphae was tested in vitro through association with the Lactobacillus strains. After that, we verified the ability of these strains to attenuate experimental candidiasis in a Galleria mellonella model through a survival curve assay. Regarding the filamentation assay, a significant reduction in hyphae formation of up to 57% was observed when C. albicans was incubated in the presence of the Lactobacillus strains, compared to a control group composed of only C. albicans. In addition, when the larvae were pretreated with Lactobacillus spp. prior to C. albicans infection, the survival rate of G. mellonela increased in all experimental groups. We concluded that Lactobacillus influences the growth and expression C. albicans virulence factors, which may interfere with the pathogenicity of these microorganisms.  相似文献   

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Plant leucine-rich repeats receptor-like kinases (LRR-RLKs) play key roles in plant growth, development, and responses to environmental stresses. However, the functions of LRR-RLKs in bryophytes are still not well documented. Here, a putative LRR-RLK gene, PnLRR-RLK, was cloned and characterized from the Antarctic moss Pohlia nutans. Phylogenetic analysis revealed that PnLRR-RLK protein was clustered with the Arabidopsis thaliana LRR XI family proteins. Subcellular localization analysis of PnLRR-RLK revealed that it was mainly localized on plasma membrane. The expression of PnLRR-RLK was induced by mock high salinity, cold, drought, and exogenously supplied abscisic acid (ABA) and methyl jasmonate (MeJA). Meanwhile, the overexpression of PnLRR-RLK showed an increased tolerance of transgenic Arabidopsis to salt and ABA stresses than that of the wild type (WT) plants. Furthermore, the expression levels of several salt tolerance genes (AtHKT1, AtSOS3, AtP5CS1, and AtADH1) and an ABA negatively regulating gene AtABI1 were significantly increased in transgenic plants. Meanwhile, the expression levels of ABA biosynthesis genes (AtNCED3, AtABA1, and AtAAO3) and ABA early response genes (AtMYB2, AtRD22, AtRD29A, and AtDREB2A) were decreased in transgenic Arabidopsis after salt stress treatment. Therefore, these results suggested that PnLRR-RLK might involve in regulating salt stress-related and ABA-dependent signaling pathway, thereby contribute to the salinity tolerance of the Antarctic moss P. nutans.  相似文献   

15.
Anthocyanin pigmentation of various organs develops during plant ontogeny in response to adverse and damaging abiotic and biotic stressors (environmental factors). Using the monosome method, the genes responsible for anther and culm anthocyanin pigmentation (Pan1 and Pc2, respectively) were localized to 7D chromosome in introgressive lines from crosses between common wheat Triticum aestivum L. and the species Triticum timopheevii Zhuk. Genetic analysis of ten common wheat genotypes using testers carrying genes Pan1, Pc1 and Pc2 showed that these genotypes contained Pan1 and Pc2 genes. Visual examination of plants from 70 and 76 varieties of respectively winter and spring common wheat revealed anthocyanin pigmentation of anthers and culms in 36 varieties. Pan1 and Pc2 genes were presumably introduced into common wheat from Aegilops tauschii (Eig.) Tzvel., a donor of the D genome.  相似文献   

16.
Stability of whey protein-pectin complexes is an essential criterion for their application in different food matrices. The impact of process parameters on micro- and macro-structural characteristics of thermally stabilised whey protein-pectin complexes was investigated using fluorescence spectroscopy, ζ-potential measurements, dynamic light scattering and phase separation. Complexes prepared from whey protein isolate (WPI) and pectins with different degrees of esterification (HMP, LMP) were generated at different biopolymer concentrations (WPI + pectin: 5.0 % + 1.0 %, c h i g h ; 2.75 % + 0.55 %, c m e d ; 0.5 % + 0.1 %, c l o w ), heating temperatures (80-90°C) and pH levels (6.1-4.0). Micro- and macro-structural characteristics of the complexes depended on concentration level and degree of esterification, with complexes being more sensitive towards environmental changes at c l o w than at c m e d and c h i g h . WPI-LMP complexes exhibited sizes <1 μm suitable for micro-encapsulation, whereas WPI-HMP complexes at c m e d achieved sizes from 1-10 μm and at c h i g h from 10-200 μm underlining their potential as fat-replacers and structuring agents, respectively. Slopes and intercepts derived from intensity ratios of fluorescence spectra gave insights into the state of unfolding of β-lactoglobulin within the complexes and thus about the protective effect of pectin addition.  相似文献   

17.
The present study was undertaken to detect the occurrence of beta-lactamase-/AmpC-producing Klebsiella and Escherichia coli in healthy pigs, feed, drinking water, and pen floor or surface soil. The study also intended to detect the clonal relationship between the environmental and porcine isolates to confirm the route of transmission. Rectal swabs and environmental samples were collected from apparently healthy pigs kept in organized or backyard farms in India. The pigs had no history of antibiotic intake. Production of phenotypical beta-lactamase, associated genes, and class I integron gene was detected in E. coli and Klebsiella isolates. The phylogenetic relationship among the isolates was established on the basis of Random amplification of polymorphic DNA banding pattern. Beta-lactamase-producing Klebsiella were isolated from healthy pigs (20.0%), pen floor swabs/surface soil swabs (14.0%), and drinking water (100%). Escherichia coli isolated from healthy pigs (14.4%), pen floor/surface soil (8.0%), and drinking water (33.3%) were detected as beta-lactamase producers. Majority of beta-lactamase-producing isolates possessed blaCTX-M-9. Further, 35 (81%) Klebsiella and all the E. coli isolates were detected as AmpC beta-lactamase ACBL producers and possessed blaAmpC. Sixteen beta-lactamase-producing Klebsiella (37.20%) and 13 E. coli (86.67%) possessed class I integron. Few resistant isolates from environmental sources (surface soil swab and drinking water) and the studied pigs were detected within the same cluster of the dendrogram representing their similarities. The study indicated about the possible role of contaminated environment as a source of beta-lactamase/AmpC-producing Klebsiella and E. coli in pigs.  相似文献   

18.
It is known that somatic mutations arising during animal growth and ageing contribute to the development of neurodegenerative and other animal diseases. For plants, several studies showed that small-scale somatic DNA mutations accumulated during Arabidopsis life cycle. However, there is a lack of data on the influence of environmental stresses on somatic DNA mutagenesis in plants. In this study, we analyzed the effects of ultraviolet C (UV-C) irradiation, high soil salinity, and cadmium (CdI3) stresses on the level of small-scale somatic DNA mutations in Arabidopsis thaliana. The number of DNA mutations was examined in the Actin2 3′UTR (Actin-U1), ITS1-5.8rRNA-ITS2 (ITS), and ribulose-1,5-biphosphate carboxylase/oxygenase (rbcL) DNA regions. We found that somatic mutation levels considerably increased in CdI3-treated Arabidopsis plants, while the mutation levels declined in the UV-C- and NaCl-treated A. thaliana. Cadmium is a mutagen that is known to inhibit DNA repair processes. The detected stress-induced alterations in somatic DNA mutation levels were accompanied by markedly increased expression of base excision repair genes (AtARP, AtDME, AtDML2, AtDML3, AtMBD4, AtROS, AtUNG, and AtZDP), nucleotide excision repair genes (AtDDB1a, AtRad4, and AtRad23a), mismatch repair genes (AtMSH2, AtMSH3, and AtMSH7), and photoreactivation genes (AtUVR2, AtUVR3). Thus, the results demonstrated that UV-C, high soil salinity, and cadmium stresses influence both the level of DNA mutations and expression of DNA repair genes. Salt- and UV-induced activation of DNA repair genes could contribute to the stress-induced decrease in somatic mutation level.  相似文献   

19.
Although the area of Lake Yeniça?a is a potential candidate for RAMSAR convention, several anthropogenic factors compromise its biological diversity. This is mostly due to nutrient-rich water released from both point and nonpoint sources. Thirteen ostracod taxa (Candona neglecta, C. candida, Ilyocypris bradyi, Darwinula stevensoni, Cypridopsis vidua, Physocypria kraepelini, Cypria ophtalmica, Prionocypris zenkeri, Eucypris virens, Herpetocypris reptans, Pseudocandona compressa, Fabaeformiscandona fabaeformis Potamocypris cf. fulva) were found during this study. Potamocypris cf. fulva is a new record for the Turkish freshwater ostracod fauna. The first nine of these species have broad geographic ranges, implying high tolerance levels to different environmental variables. Based on the estimated species optima and tolerance levels, two species exhibited higher effective number of occurrences (C. neglecta, and D. stevensoni, respectively) than the other species. Three species (C. neglecta, D. stevensoni, I. bradyi) did not show significant correlation with any environmental variable we used. Both Canonical correspondence (CCA) and Pearson correlation analyses showed that temperature was the most effective predictor of species occurrence, followed by electrical conductivity and redox potential. In contrast, pH and dissolved oxygen of water were the least effective predictors. Approximately 71% of the correlation between community composition and environmental variables was explained by the first axis of the CCA diagram, which had a relatively low (7.7%) cumulative variance of species. The lower (560 μg/l) and the upper (2030 μg/l) levels of ammonia (NH3) exceeded the limits during winter season. The concentrations of total coliform and Escherichia coli bacteria were measured up to 10 × 107 cfu/ml and 10 × 103 cfu/ml, respectively. Results of physicochemical measurements, microbiological counts, and species data indicate that water quality of Lake Yeniça?a has been rapidly deteriorated by anthropogenic factors that are the main threat for not only the lake’s aquatic diversity but also human health around the lake.  相似文献   

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