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231.
Global warming is negatively affecting the environment of the planet. This situation has led to the development of international standards, such as the International Organisation for Standardization's DIS 14064‐1 and the Greenhouse Gas Protocol Corporate Standard, both of which measure corporate carbon footprints. These standards provide guidelines that can be applied to different organizational sectors. However, these are not sufficient for controlling the reduction of carbon emissions, because although they propose the use of indicators, they do not explicitly define them. In addition, in the case of emissions from wastewater treatment, they only suggest that the emissions associated with this process be considered. In the present study, an eight‐step, unified methodology based on these two international standards is proposed, focusing on direct emissions. Moreover, the step‐by‐step to data collection, calculations, and the required indicators to control the emissions are defined. The first scope considers direct emissions from sources that are owned or controlled by the company. Methane generation measurement from wastewater treatment has been included in the methodology within Scope 1, as it is the second most polluting gas after carbon dioxide, both of which give rise to global warming. The proposed methodology was tested as a case study in one of the most important companies in the food sector in Colombia. 相似文献
232.
Izaskun Zorita Joana Larreta Natalia Montero José Germán Rodríguez Javier Franco Ángel Borja 《Chemistry and Ecology》2013,29(5):432-445
Bioaccumulation and biological effects of pollution were assessed in mussels (Mytilus galloprovincialis) caged for one month at three sites in the Oiartzun estuary (south-eastern Bay of Biscay, Spain) with the aim of evaluating their usefulness within the investigative monitoring defined in the European Union Water Framework Directive (WFD). The highest concentrations of organic contaminants determined in mussels' tissue were detected towards the inner part of the estuary but no gradient pattern was found for metal bioaccumulation. Population fitness responses measured as condition index, stress on stress and gonad index were similar in all caged mussels and did not follow the organic pollution gradient. However, biomarkers determined at tissue, cell and protein level (histopathology, micronuclei frequency, malondialdehyde levels and vitellogenin-like protein levels) revealed a higher stress syndrome at the inner part of the estuary showing signs of genotoxicity, oxidative stress and endocrine disruption. Overall, the integrated chemical–biological approach in connection with mussel caging technique proved to be a useful tool to assess environmental pollution, allowing a better understanding of the cause–effect relationship within the investigative monitoring defined in the WFD. 相似文献
233.
Carolina Oliveira de Santana Taíse Bomfim de Jesus William Moura de Aguiar Washington de Jesus Sant’anna Franca-Rocha Carlos Alberto Caroso Soares 《Environmental monitoring and assessment》2017,189(3):123
In this study, an analysis was performed on the concentrations of the trace elements Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in muscle of two carnivorous and one planktivorous fish species collected at Todos os Santos Bay (BTS). The accumulation order of the trace elements in Lutjanus analis was Al >Zn >Fe >Cr >Ba >Ni. In Cetengraulis edentulus, the order was Al >Fe >Zn >Cr >Ni >Mn >As. In the species Diapterus rhombeus, the order was Al >Fe >Zn >Cr >Ni >Mn >Cd. To determine the risk related to the consumption of fish, toxicity guidelines were used as standard references. It was observed that the species C. edentulus contained concentrations of As exceeding WHO limits, but these concentrations were acceptable according to the Agência Nacional de Vigilância Sanitária (ANVISA) guidelines. Cd levels were found only in D. rhombeus and in low concentrations according to the determinations of WHO and ANVISA. Pb levels were not detected in any of the three fish species. The analyzed elements did not differ statistically according to the species and feeding habits. The results point to possible risks of human contamination by As related to the consumption of the fish species C. edentulus from the BTS. 相似文献
234.
Chromium toxicity in plants 总被引:56,自引:0,他引:56
Due to its wide industrial use, chromium is considered a serious environmental pollutant. Contamination of soil and water by chromium (Cr) is of recent concern. Toxicity of Cr to plants depends on its valence state: Cr(VI) is highly toxic and mobile whereas Cr(III) is less toxic. Since plants lack a specific transport system for Cr, it is taken up by carriers of essential ions such as sulfate or iron. Toxic effects of Cr on plant growth and development include alterations in the germination process as well as in the growth of roots, stems and leaves, which may affect total dry matter production and yield. Cr also causes deleterious effects on plant physiological processes such as photosynthesis, water relations and mineral nutrition. Metabolic alterations by Cr exposure have also been described in plants either by a direct effect on enzymes or other metabolites or by its ability to generate reactive oxygen species which may cause oxidative stress. The potential of plants with the capacity to accumulate or to stabilize Cr compounds for bioremediation of Cr contamination has gained interest in recent years. 相似文献
235.
Edumar Ramos Cabral Coelho Lorena Frasson Loureiro Miguel Angelo Schettino Jr. Jair Carlos Checon de Freitas 《Journal of environmental science and health. Part. B》2020,55(4):361-375
AbstractActivated carbons are well-known porous materials as an effective adsorbent used for the removal of emerging contaminants, such as herbicides, which are increasingly present in water bodies. Most water treatment plants, specially in Brazil, are unable to completely remove such contaminants by the conventional process and advanced treatment using activated carbons is required. The aim of this paper was to verify the influence of the activated carbons granulometry and specific surface area on the 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide removal efficiency using distilled-deionized water and filtered water collected from a conventional Water Treatment Plant. Commercial activated carbons samples used in this work were obtained from two different manufacturers. Activated carbons were analyzed by the specific surface area, pore size and volume distribution, nuclear magnetic resonance, infrared and x-ray spectroscopy, moisture, volatile matter and ash contents. Batch adsorption isotherms experiments were used and performed by Langmuir and Freundlich models. Granular and powdered activated carbons removed over 99% of 2,4-D in distilled water and near to 99% using filtered water. The activated carbons evaluated in this work presented high performance and played a key role in water treatment by removing 2,4-D herbicide, ensuring the protection of human health and the ecosystem. 相似文献
236.
State-specific detection probabilities and disease prevalence. 总被引:2,自引:0,他引:2
Christopher S Jennelle Evan G Cooch Michael J Conroy Juan Carlos Senar 《Ecological applications》2007,17(1):154-167
Investigations of disease dynamics in wild animal populations often use estimated prevalence or incidence as a measure of true disease frequency. Such indices, almost always based solely on raw counts of infected and uninfected individuals, are often used as the basis for analysis of temporal and spatial dynamics of diseases. Generally, such studies do not account for potential differences in observer detection probabilities of host individuals stratified by biotic and/or abiotic factors. We demonstrate the potential effects of heterogeneity in state-specific detection probabilities on estimated disease prevalence using mark-recapture data from previous work in a House Finch (Carpodacus mexicanus) and Mycoplasma gallisepticum system. In this system, detection probabilities of uninfected finches were generally higher than infected individuals. We show that the magnitude and seasonal pattern of variation in estimated prevalence, corrected for differences in detection probabilities, differed markedly from uncorrected (apparent) prevalence. When the detection probability of uninfected individuals is higher than infected individuals (as in our study), apparent prevalence is negatively biased, and vice versa. In situations where state-specific detection probabilities strongly interact over time, we show that the magnitude and pattern of apparent prevalence can change dramatically; in such cases, observed variations in prevalence may be completely spurious artifacts of variation in detection probability, rather than changes in underlying disease dynamics. Accounting for differential detection probabilities in estimates of disease frequency removes a potentially confounding factor in studies seeking to identify biotic and/or abiotic drivers of disease dynamics. Given that detection probabilities of different groups of individuals are likely to change temporally and spatially in most field studies, our results underscore the importance of estimating and incorporating detection probabilities in estimated disease prevalence (specifically), and more generally, any ecological index used to estimate some parameter of interest. While a mark-recapture approach makes it possible to estimate detection probabilities, it is not always practical, especially at large scales. We discuss several alternative approaches and categorize the assumptions under which analysis of uncorrected prevalence may be acceptable. 相似文献
237.
Mary F. Willson Toni L. De Santo Carlos Sabag Juan J. Armesto 《Conservation biology》1994,8(2):508-520
The diversity and relative abundance of south-temperate rainforest birds decreased as the size of the habitat patch decreased. Ecological categories, including endemics, mutualists (pollinators, seed dispersers), understory species, and species dependent on large trees, were not differentially sensitive to patch size. Nevertheless, most of the species with at least marginally significant declines were endemic (6 of 7 species), covered nesters (6 of 7 species), and understory dwellers (5 of 7 species). Some mutualists and big-tree users were also affected. The losses will become more severe as clearing of the forest continues. Possible mitigation measures include leaving small stands of forest and corridors between habitat patches and, in certain circumstances, alternative agricultural practices. 相似文献
238.
Leonardo Lavanderos M. Eugenia Pozo Carlos Pattillo Hernán Miranda 《Environmental monitoring and assessment》1990,14(1):9-22
Spatial heterogeneity of the Rapel reservoir surface waters is analyzed through Landsat images. The image digital counts are used with the aim or developing an aprioristic quantitative sample design.Natural horizontal stratification of the Rapel Reservoir (Central Chile) is produced mainly by suspended solids. The spatial heterogeneity conditions of the reservoir for the Spring 86-Summer 87 period were determined by qualitative analysis and image processing of the MSS Landsat, bands 1 and 3. The space-time variations of the different observed strata obtained with multitemporal image analysis.A random stratified sample design (r.s.s.d) was developed, based on the digital counts statistical analysis. Strata population size as well as the average, variance and sampling size of the digital counts were obtained by the r.s.s.d method.Stratification determined by analysis of satellite images were later correlated with ground data. Though the stratification of the reservoir is constant over time, the shape and size of the strata varys. 相似文献
239.
240.
The organic fraction of a municipal solid waste was added in different doses to an eroded soil formed of loam and with no
vegetal cover. After three years, the changes in macronutrient content and the chemical-structural composition of its organic
matter were studied. The addition of the organic fraction from a municipal solid waste had a positive effect on soil regeneration,
the treated soils being covered with spontaneous vegetation from 1 yr onwards. An increase in electrical conductivity and
a fall in pH were noted in the treated soils as were increases in macronutrients, particularly N and available P and the different
carbon fractions. Optical density measurements of the organic matter extracted with sodium pyrophosphate showed that the treated
soils contained an organic matter with less condensed compounds and with a greater tendency to evolve than the control. A
pyrolysis-gas chromatography study of the organic matter extracted with pyrophosphate showed large quantities of benzene both
in the treated soils and control; pyrrole was also relatively abundant, although this fragment decreased as the dose rose.
Xylenes and pyridine were present in greater quantities in the control and furfural in the treated soils. Three years after
addition to the soil, the organic matter had a higher proportion of fragments derived from aromatic compounds and a smaller
proportion derived from hydrocarbons. Similarity indices showed that, although the added and newly formed organic matter 3
yr after addition continued to differ from that of the original soil and to be more mineralizable, the transformations it
has undergone made it more similar to the original organic matter of the soil than it was at the moment of being added. 相似文献