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591.
Regional Environmental Change - Vegetation actively affects different components of the water budget in multiple spatial and temporal scales. Changes in vegetation cover and structure—such as...  相似文献   
592.
To examine how citizen-driven initiatives for sustainability strive to bring about change and spread their practices, efforts to link social movement, grassroots innovation and green-consumption movements theory are built upon. Göteborg’s citizen-driven waste-prevention initiatives, such as food waste recovery, creating common reuse spaces in housing blocks, exchanging used toys and repairing abandoned bicycles, are considered with data from observations, workshops, documents, social media communications and in-depth interviews. Citizen-driven initiatives succeeded in mobilizing material resources, displaying and reframing various rationales, and creating collaborative local networks to develop their waste-prevention practices. These practices infiltrated the municipal administration, matching incipient institutional mandates to minimize waste. By so doing, they bring within mainstream institutions radical rationales that can become activated in the future, contributing to diachronic change.  相似文献   
593.
Methane is produced in anaerobic environments, such as reactors used to treat wastewaters, and can be consumed by methanotrophs. The composition and structure of a microbial community enriched from anaerobic sewage sludge under methane-oxidation condition coupled to denitrification were investigated. Denaturing gradient gel electrophoresis (DGGE) analysis retrieved sequences of Methylocaldum and Chloroflexi. Deep sequencing analysis revealed a complex community that changed over time and was affected by methane concentration. Methylocaldum (8.2%), Methylosinus (2.3%), Methylomonas (0.02%), Methylacidiphilales (0.45%), Nitrospirales (0.18%), and Methanosarcinales (0.3%) were detected. Despite denitrifying conditions provided, Nitrospirales and Methanosarcinales, known to perform anaerobic methane oxidation coupled to denitrification (DAMO) process, were in very low abundance. Results demonstrated that aerobic and anaerobic methanotrophs coexisted in the reactor together with heterotrophic microorganisms, suggesting that a diverse microbial community was important to sustain methanotrophic activity. The methanogenic sludge was a good inoculum to enrich methanotrophs, and cultivation conditions play a selective role in determining community composition.  相似文献   
594.

In order to study the bioaccumulation of Pb, Cr, Ni, and Zn and the stress response, the floating aquatic plant Limnobium laevigatum was exposed to increasing concentrations of a mixture of these metals for 28 days, and its potential use in the treatment of wastewater was evaluated. The metal concentrations of the treatment 1 (T1) were Pb 1 μg L−1, Cr 4 μg L−1, Ni 25 μg L−1, and Zn 30 μg L−1; of treatment 2 (T2) were Pb 70 μg L−1, Cr 70 μg L−1, Ni 70 μg L−1, and Zn 70 μg L−1; and of treatment 3 (T3) were Pb 1000 μg L−1, Cr 1000 μg L−1, Ni 500 μg L−1, and Zn 100 μg L−1, and there was also a control group (without added metal). The accumulation of Pb, Cr, Ni, and Zn in roots was higher than in leaves of L. laevigatum, and the bioconcentration factor revealed that the concentrations of Ni and Zn in the leaf and root exceeded by over a thousand times the concentrations of those in the culture medium (2000 in leaf and 6800 in root for Ni; 3300 in leaf and 11,500 in root for Zn). Thus, this species can be considered as a hyperaccumulator of these metals. In general, the changes observed in the morphological and physiological parameters and the formation of products of lipid peroxidation of membranes during the exposure to moderate concentrations (T2) of the mixture of metals did not cause harmful effects to the survival of the species within the first 14 days of exposure. Taking into account the accumulation capacity and tolerance to heavy metals, L. laevigatum is suitable for phytoremediation in aquatic environments contaminated with moderated concentrations of Cr, Ni, Pb, and Zn in the early stages of exposure.

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595.
In our study, we aimed to investigate the influence of landscape patterns on the diversity of birds in four urban parks. The parks are located in a region that has a high value of regional biodiversity and is also highly urbanized (Jundiai, state of São Paulo [SP], in Southeastern Brazil). Using a set of aerial photos, the surrounding landscape was divided into two regions (rings) and corresponding landscape metrics were calculated. The presence of bird species was recorded monthly over a one‐year period and classified according to selected ecological criteria. The land cover of the areas surrounding each park was primarily buildings and residences. Bird diversity was significantly correlated with the presence/proximity of water bodies. We state that the potential of the parks to harbor bird species is not negligible. Managing the area surrounding a park to increase the percentage of forested area and the size of forest fragments is as crucial as managing the core park area, especially for improving its attractiveness for new bird species.  相似文献   
596.
Based on the national database of 28,104 water rights (concessions) granted in Colombia, this paper presents an analysis of how the principles of equity and sustainability are reflected in water allocation. Concessions appear to be an exclusionary mechanism since only a minority of small water users have concessions and the distribution of water volumes among those who have them is extremely inequitable. The 2009 Gini coefficient calculated for water concessions granted for agriculture was 0.90 compared with the rural land Gini of 0.88 (both indicators grouping holdings under the same entity). More than half of the Colombian departments have a higher Gini coefficient for water than for land, suggesting that water rights are at least as unequally distributed as land, in one of the most inequitable countries in Latin America. Water allocated to domestic, agriculture and hydropower use indicates a lack of consistency of water allocation criteria across regions. The volumetric and administrative attributes of water allocation in Colombia do not account for environmental flows or the concerns of marginalised groups of society that have limited access to the mechanism. Water allocation as a technical task, with limited transparency and secluded from public scrutiny, does not contribute to the solution of increasing water-related conflicts.  相似文献   
597.

Social acceptance is fundamental, and directly affects the installation of wind farms. In this paper, the factors that have had the greatest influence on the development of wind energy in the Itsmo region of Tehuantepec, Mexico are identified. The data were collected face to face through a semi-structured questionnaire of 31 people: owners, municipal authorities, opposition groups, and academic members. The results of the interview highlight the social impact, the lack of application, and concerning ILO Convention 169, the abuse of community rights. As a result, people interviewed perceive that the environmental impact of the installation, and operation of wind farms has been ambivalent: positive due to the intrinsic benefits that wind energy generates compared to other energy sources, and negative in terms of affectation by the noise, and the landscape. However, the income received by the owners of land in which wind facilities are located is lower compared to other parts of the world. In general, the facts show a disintegration between the authorities (federal, state, and municipal), universities are isolated from wind projects, communities are not consulted in projects, and large companies are the main beneficiaries.

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598.
Environment, Development and Sustainability - Although sustainability assessment is widely discussed at Brazil, in Brazilian Amazon its use is still little applied, considering this territory is...  相似文献   
599.
The present study sought to objectively demonstrate how a researcher can, in a structured way, select relevant articles about alternative heterogeneous catalysts in photocatalytic processes. Therefore, the ProKnow-C (Knowledge Development Process – Constructivist) method was used to systematize the results found, with the application bibliometric and systematic analysis techniques for the evaluation of the results. The search string adopted as criteria was: solar photocatalysis AND heterogeneous catalysts OR alternative catalysts AND effluents. The databases were Web of Science, Science Direct and Scopus. The final bibliographic portfolio obtained for the research theme was made up of 19 articles. It was possible to verify advances in the number of publications on the theme over the evaluated period, with the Journal of Photochemistry and Photobiology A: Chemistry standing out in the final portfolio. Evaluating each article in the portfolio individually, it was possible to verify that most studies use combinations of catalysts already reported to create an alternative material to those already investigated in the literature. Those that use waste as catalysts chose to source this material from treatment plants and the steel industry. Around 58% of the papers used hydrogen peroxide in their processes, while 42% chose not to use it. Finally, approximately 63% of the papers in the portfolio used synthetic effluent in their processes, while the rest (37% of the research) chose to use real effluent. The results obtained in this research by applying the method can contribute to studies related to heterogeneous photocatalysis by alternative means over the years.  相似文献   
600.
The present study evaluated the effect of culture conditions and phytopathogenic strain co-culture on the production of antimicrobial metabolites and antifungal activity of Penicillium chrysogenum R1, which PCR identified. Antimicrobial activity was determined using the Hunter-Hunter experimental design with three factors (pH, incubation temperature, and inoculum, at two levels each). The antifungal metabolites, β 1-3 glucanase and chitinase, produced in the presence of live and inactivated Fusarium oxysporum Fsox C11 biomass, were evaluated using HPLC-MS and GC-MS. Results showed that P. chrysogenum inhibited the growth of five phytopathogenic fungal strains, and the most significant inhibition was observed for F. oxysporum Fsox C11. The best conditions to achieve the highest antifungal activity of the cell-free extract were pH 7, 28°C, 1 × 106 spores/mL, and 144 h of fermentation, observing 86% inhibition of F. oxysporum Fsox C11 growth. Production of antifungal metabolites such as 1,4-benzoquinone imine, viridicatic acid, phenol-5-methyl-2-(1-methyl ethyl), and hydrolytic enzymes β 1-3 glucanase and chitinase was detected. The results define the perspective in designing new processes and products for biocontrol phytopathogens.  相似文献   
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