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181.
Environment, Development and Sustainability - Realisation of the sustainable development goals (SDGs) will provide improvements to people's lives and longevity of the planet. The architectural,...  相似文献   
182.
Maintaining and enhancing ecosystem services through the restoration of degraded ecosystems have become an important biodiversity conservation strategy. Deciding where to restore ecosystems for the attainment of multiple services is a key issue for future planning, management, and human well-being. Most restoration projects usually entail a small number of actions in a local area and do not consider the potential benefits of planning restoration at broad regional scales. We developed a hierarchical priority setting approach to evaluate the performance of restoration measures in a semiarid basin in NE Spain (the Martín River Basin, 2,112 km2). Our analysis utilized a combination of erosion (a key driver of degradation in this Mediterranean region) and six spatially explicit ecosystem services data layers (five of these maps plotted surrogates for soil retention and accumulation, water supply and regulation, and carbon storage, and one plotted a cultural service, ecotourism). Hierarchical maps were generated using a geographic information system that combined areas important for providing a bundle of ecosystem services, as state variables, with erosion maps, as the disturbance or regulatory variable. This was performed for multiple scales, thereby identifying the most adequate scale of analysis and establishing a spatial hierarchy of restoration actions based on the combination of the evaluation of erosion rates and the provision of ecosystem services. Our approach provides managers with a straightforward method for determining the spatial distribution of values for a set of ecosystem services in relation to ecological degradation thresholds and for allocating efforts and resources for restoration projects in complex landscapes.  相似文献   
183.
Regional Environmental Change - Across the country, government agencies increasingly collaborate with non-governmental actors on environmental dilemmas to gain access to resources, expertise, and...  相似文献   
184.
Enhanced bioremediation is quickly developing into an economical and viable technology for the remediation of contaminated soils. Until recently, chlorinated organic compounds have proven difficult to bioremediate. Environmentally recalcitrant compounds, such as polychlorinated biphenyls (PCBs) and persistent organic pesticides (POPs) such as dichlorodiphenyl trichloroethane (DDT) have shown to be especially arduous to bioremediate. Recent advances in field‐scale bioremedial applications have indicated that biodegradation of these compounds may be possible. Engineers and scientists at the Savannah River Site (SRS), a major DOE installation near Aiken, South Carolina, are using enhanced bioremediation to remediate soils contaminated with pesticides (DDT and its metabolites, heptachlor epoxide, dieldrin, and endrin) and PCBs. This article reviews the ongoing remediation occurring at the Chemicals, Metals, and Pesticides (CMP) Pits using windrow turners to facilitate microbial degradation of certain pesticides and PCBs. © 2003 Wiley Periodicals, Inc.  相似文献   
185.
Mineralization potentials are often used to classify organic wastes. These methods involve measuring CO2 production during batch experiments, so variations in chemical compounds are not addressed. Moreover, the physicochemical conditions are not monitored during the reactions. The present study was designed to address these deficiencies. Incubations of a mixture of soil and waste (vinasse at 20% dry matter from a fermentation industry) were conducted in aerobic and anaerobic conditions, and liquid samples obtained by centrifugation were collected at 2 h, 1 d and 28 d. Dissolved organic carbon (DOC) patterns highlighted that: there was a “soil effect” which increased organic matter (OM) degradation in all conditions compared to vinasse incubated alone; and OM degradation was faster under aerobic conditions since 500 mg kg?1 of C remained after aerobic incubation, as compared to 4000 mg kg?1 at the end of the anaerobic incubation period. No changes were detected by Fourier transform infrared spectroscopy (FTIR) between 2 h and 1 d incubation. At 28 days incubation, the FTIR signal of the aerobic samples was deeply modified, thus confirming the high OM degradation. Under anaerobic conditions, the main polysaccharide contributions (ν(C–O)) disappeared at 1000 and 1200 cm?1, as also confirmed by the 13C NMR findings. Under aerobic incubation, a 50% decrease in the polysaccharide proportion was observed. Under anaerobic conditions, significant chemical modifications of the organic fraction were detected, namely formation of low molecular weight organic acids.  相似文献   
186.
Tourists are particularly vulnerable when natural disasters occur in regions that they are visiting. It is assumed that they lack awareness and understanding of the actions that they need to take in such circumstances. This study examines the responses of tourists in times of disaster, building on empirical data collected through large‐scale surveys conducted in Bali and Yogyakarta, Indonesia, in 2015. Both are important tourist destinations in the country that have suffered major disasters in recent years. The different types of responses to these events are framed using a grid/group analysis stemming from cultural theory. The study resulted in three key findings: (i) current disaster management planning largely follows a single rationale; (ii) tourists are not a homogeneous group, but rather a complex, diverse, and dynamic body of stakeholders; and (iii) the focus of disaster management planning should shift from a single rationale to a polyrational methodology. Disaster managers need to consider, therefore, these different aspects in the context of preparedness.  相似文献   
187.
Anthropogenic contaminants like nonylphenols (NP) are added to soil, for instance if sewage-sludge is used as fertilizer in agriculture. A commercial mixture of NP consists of more than 20 isomers. For our study, we used one of the predominate isomers of NP mixtures, 4-(3,5-dimethylhept-3-yl)phenol, as a representative compound. The aim was to investigate the fate and distribution of the isomer within soil and soil derived organo-clay complexes. Therefore, 14C- and 13C-labeled NP was added to soil samples and incubated up to 180 days. Mineralization was measured and soil samples were fractionated into sand, silt and clay; the clay fraction was further separated in humic acids, fulvic acids and humin. The organo-clay complexes pre-incubated for 90 or 180 days were re-incubated with fresh soil for 180 days, to study the potential of re-mobilization of incorporated residues. The predominate incorporation sites of the nonylphenol isomer in soil were the organo-clay complexes. After 180 days of incubation, 22 % of the applied 14C was mineralized. The bioavailable, water extractable portion was low (9 % of applied 14C) and remained constant during the entire incubation period, which could be explained by an incorporation/release equilibrium. Separation of organo-clay complexes, after extraction with solvents to release weakly incorporated, bioaccessible portions, showed that non-extractable residues (NER) were preferentially located in the humic acid fraction, which was regarded as an effect of the chemical composition of this fraction. Generally, 27 % of applied 14C was incorporated into organo-clay complexes as NER, whereas 9 % of applied 14C was bioaccessible after 180 days of incubation. The re-mobilization experiments showed on the one hand, a decrease of the bioavailability of the nonylphenol residues due to stronger incorporation, when the pre-incubation period was increased from 90 to 180 days. On the other hand, a shift of these residues from the clay fraction to other soil fractions was observed, implying a dynamic behavior of incorporated residues, which may result in bioaccessibility of the NER of nonylphenol.  相似文献   
188.
Oil pollution from various sources, including exploration, production and transportation, is a growing global concern. The highest toxicity of hydrocarbon pollutants is associated with the water-soluble phase compounds, including naphthenic acids, a known component found in all hydrocarbon deposits. Recently, naphthenic acids (NAs) have shown estrogenic and anti-androgenic effects in vitro. For this reason we investigated the potential effects of two commercial mixtures of naphthenic acids on fish in vivo, using the three-spined stickleback (Gasterosteus aculeatus) as a model species.  相似文献   
189.
Photocatalytic degradation of dissolved organic carbon (DOC) by utilizing Fe(III)-doped TiO2 at the visible radiation range is hereby reported. The photocatalyst was immobilized on sintered glass frits with the coating done by wet method, calcinated at 500 °C and then applied in a photodegradation reactor. The addition of a transition metal dopant, Fe(III), initiated the red shift which was confirmed by UV–Vis spectroscopy, and the photocatalyst was activated by visible radiation. X-ray diffraction patterns showed that Fe(III) doping had an effect on the crystallinity of the photocatalysts. Mixtures of DOC and associated coloured solutions were degraded in first-order kinetics, showing that the degradation process was not dependent on intermediates or other species in solution. A reactor with a catalyst coating area of 12.57 cm2 was able to degrade 0.623 mg of the dissolved material per minute. Exposure of the reactor to hostile acidic conditions and repeated use did not compromise its efficiency. It was observed that the reactor regenerates itself in the presence of visible light, and therefore, it can be re-used for more than 100 runs before the performance dropped to <95 %. The results obtained indicate that the photocatalyst reactor has a great potential of application for use in tandem with biosorbent cartridges to complement water purification methods for domestic consumption.  相似文献   
190.
ABSTRACT

A previous paper1 discusses the methodology for a new method for deriving the nitrogen dioxide/nitrogen oxide (NO2/NOx) ratio in plumes that originally are composed mainly of (NOx). It is called the Plume Volume Molar Ratio Method (PVMRM). This paper documents its performance against six different data sets. These performance evaluations show that the PVMRM can realistically predict the NO2 fraction at close-in receptors yet still provide conservative estimates so that the air quality standards can be protected.  相似文献   
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