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1.
Soft bottom benthic organisms especially polychaetes are known to adapt as r or k selected strategies to different gradients of pollution. This will result in changes of benthic community structure from that of normal structure. There are a number of techniques to assess the impact of pollution on benthic community structure. Hence, to test this hypotheses some of the univariate and multivariate techniques were applied to soft bottom macro-invertebrates data of coastal waters of Mangalore, central west coast of India, a hot-spot area. Univariate techniques such as Pearson Rosenberg Model (PRM), abundance biomass comparison curve (ABC), geometrical class distribution, dominance-diversity curve, benthic community structure indices and multivariate techniques such as cluster classification, multidimensional scaling (MDS) and principal component analysis (PCA) were used to discriminate and diagnose the disturbance among the sites. Effectiveness and applicability of some of the above techniques are highlighted and discussed with the present set of data for environmental impact assessment studies.  相似文献   
2.

Natural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities of Euphorbia resinifera and Euphorbia officinarum aqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected in E. officinarum honey, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared with E. resinifera honey, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 - 2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.

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3.
Torque teno virus (TTV) was surveyed in tap water collected in schools from three municipalities located in the south of Brazil. TTV genomes were found in 11.7 % (4/34) of the samples. TTV DNA was detected in 10.5 % (2/19) of the samples collected at the city of Caxias do Sul and in 25 % (2/8) of the samples from Pelotas. Those cities have a low rate of sewage treatment. All samples from Santa Cruz do Sul, which has nearly 92 % of its sewage treated, were negative. These results suggest that the amount of sewage treated may have an effect on the detection rates of TTV DNA in drinking water in a given urban area, showing a mild negative correlation (r = ?0.76), when comparing the percentage of sewage treatment to the detection of TTV genomes. The detection rate of TTV was also compared with Escherichia coli, showing a strong correlation (r = 0.97), indicating that TTV may be a suitable marker of fecal contamination.  相似文献   
4.
This paper sets out to describe the environmental impact assessment for wood charcoal briquettes produced from eucalyptus wood in Brazil, with specific reference to those impacts associated with Global Warming Potential. To achieve that objective, the work was undertaken in accordance with ISO 14040 "Environmental management - Life cycle assessment - Principles and framework" which describes essential LCA characteristics and good practices. Charcoal briquettes are produced from two basic raw materials, charcoal fines and starch. The fines result from the production of charcoal from sustainably managed eucalyptus plantations. Starch is extracted from babaçu pulp in the Amazon region. Multi-output processes were allocated based on income from the different by-products. The results showed that more than 90% of incoming CO2 was due to biomass production for charcoal, and the remainder to starch biomass production. Based on Brazilian data, as well as information provided by the GaBi4.3 database, it turned out that supplying the energy content of 1 kg of briquettes resulted in the sequestration of 3.9690 kg of CO2, i.e. around 4 kg of CO2 per kg of briquettes produced. CO2 emissions throughout the briquette production process are totally compensated for by the environmental quality of the raw materials used.  相似文献   
5.
This paper describes the study that led to the development of a carbon dioxide emissions matrix for the Oeiras municipality, one of the largest Portuguese municipalities, located in the metropolitan area of Lisbon. This matrix takes into account the greenhouse gas (GHG) emissions due to an increase of electricity demand in buildings as well as solid and liquid wastes treatment from the domestic and services sectors. Using emission factors that were calculated from the relationship between the electricity produced and amount of treated wastes, the GHC emissions in the Oeiras municipality were estimated for a time series of 6 yr (1998-2003). The obtained results showed that the electricity sector accounts for approximately 75% of the municipal emissions in 2003. This study was developed to obtain tools to base options and actions to be undertaken by local authorities such as energy planning and also public information.  相似文献   
6.
In this study, we seek to verify the contributions made by three international standards to efforts by eight companies to reduce their environmental impacts and move toward sustainable development. The standards considered in this article are the International Organization for Standardization's (ISO) 9001 (quality), ISO 14001 (environmental management systems), and the Occupational Health and Safety Assessment Series (OHSAS) 18001. The eight companies analyzed for this study are located in the state of Rio Grande do Sul in Brazil. As part of this work, the authors generated a proposed sustainable positioning matrix and placed each company within one of four quadrants—economic approach, environmental approach, social approach, and sustainability approach—derived from the context of the Triple Bottom Line (Elkington, 2004 ).  相似文献   
7.
Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues.  相似文献   
8.
Journal of Material Cycles and Waste Management - The use of lignocellulosic fibers as fillers in polymer matrices has aroused the interest of the scientific community and industrial sectors. In...  相似文献   
9.
Environmental Management - Groundwater is one of the main resources for social-ecological systems. As part of the total water cycle and deeply connected with land use, groundwater management faces...  相似文献   
10.
When applied to agricultural soils, phosphate fertilizers and the mineral or organic compounds present in solid and/or liquid waste may raise phosphorus (P) content and increase soil P saturation. The degree of phosphorus saturation (DPS) is a good indicator of potential P loss from agricultural soils. The purpose of this study was to calculate the DPS of samples from an Oxisol amended for 5 years with biosolids and mineral fertilizer. DPS was calculated based on P, iron, and aluminum extracted by ammonium oxalate and oxalic acid (DPSox) or by Mehlich-1 solution (DPSM1). Treatments included NPK mineral fertilization (175 kg ha?1 of P), B1?=?19.02 t ha?1 of biosolids (350 kg ha?1 of P), B2?=?38.17 t ha?1 of biosolids (703 kg ha?1 of P), B3?=?76.26 t ha–1 of biosolids (1,405 kg ha?1 of P), and a control (no P added). Water-extractable P (WEP) was also measured. Critical levels of DPSox and DPSM1 (21 and 24 %, respectively) were only achieved in the topsoil (0–0.1 m) at the highest biosolid dose. Concentration of WEP was positively correlated to DPSox and DPSM1. The DPSM1 method may be an alternative to DPSox for assessing the environmental risk of P loss from soil into surface runoff.  相似文献   
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