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991.
China is a large densely populated country undergoing rapid industrialization and is becoming one of the world's biggest consumers of natural resources. This circumstance provides a sharp contrast with other countries. As China is so significant in the global economy, studies of its eco-industrial development are very important. In this study we examined the state of eco-industrial development in China and have drawn conclusions from this analysis about some of the future prospects for sustainable development. In the analysis, we investigated the application of industrial ecology concepts by reference to several case studies. We have therefore described the current environmental situation in China, and have provided an overview of eco-industrial development and its implementation. Constraints to industrial sustainability in China have also been examined. We consider that eco-industrial development in China is in its infancy, and that closed loops involving chains and industrial symbiotic webs are the technological key and core of successful initiatives in the application of industrial ecology. In the case studies, we found that each system has different characteristics and management concerns. Our major conclusion is that even though China's Agenda 21 highlights the principles and sets the directions for eco-industrial development, these have not yet become essential ingredients in the country's industrial policy and practice for implementing Agenda 21.  相似文献   
992.
This paper presents a hybrid technology of soil remediation based on the integration of biodegradation and electroosmosis. We employed soils with different texture (clay soil and loamy sand) containing a mixture of polycyclic aromatic hydrocarbons (PAH) present in creosote, and inoculation with a representative soil bacterium able to degrade fluorene, phenanthrene, fluoranthene, pyrene, anthracene, and benzo[a]pyrene. Two different modes of treatment were prospected: (i) inducing in soil the simultaneous occurrence of biodegradation and electroosmosis in the presence of a biodegradable surfactant, and (ii) treating the soils sequentially with electrokinetics and bioremediation. Losses of PAH due to simultaneous biodegradation and electroosmosis (induced by a continuous electric field) were significantly higher than in control cells that contained the surfactant but no biological activity or no current. The method was especially successful with loamy sand. For example, benzo[a]pyrene decreased its concentration by 50% after 7 d, whereas 22 and 17% of the compound had disappeared as a result of electrokinetic flushing and bioremediation alone, respectively. The use of periodical changes in polarity and current pulses increased by 16% in the removal of total PAH and in up to 30% of specific compounds, including benzo[a]pyrene. With the aim of reaching lower residual levels through bioremediation, an electrokinetic pretreatment was also evaluated as a way to mobilize the less bioaccessible fraction of PAH. Residual concentrations of total biodegradable PAH, remaining after bioremediation in soil slurries, were twofold lower in electrokinetically pretreated soils than in untreated soils. The results indicate that biodegradation and electroosmosis can be successfully integrated to promote the removal of PAH from soil.  相似文献   
993.
This study has as its aim to help to clarify the relationship between environmental management and economic performance by integrating it into a wider framework that includes the relationship between environmental strategy and firm performance, the latter being understood as the combination of environmental performance, competitive advantage and economic performance. A case study of the COATO farming cooperative showed us that its environmental management, focused on prevention logic, has had a positive net effect on its environmental performance. Besides, the order in which these practices were adopted favoured the development of new organisational capabilities that have contributed to the appearance of advantages derived from the greater accumulated experience of employees in creating new projects that are designed to reduce residues and pollution. COATO has also obtained a competitive advantage in differentiation thanks to an improved brand image and to its increased credibility in business relationships. Finally, a positive correlation exists between the pioneering proactive strategy adopted by this cooperative and the improvement of its firm performance with respect to the other firms in its sector.  相似文献   
994.
In this contemporary interpretation of the widespread land degradation problem in Southeast Asia, it is hypothesized that spatial interplay of environmental and socioeconomic predictors determines the occurrence of land degradation. Village surveys, remote sensing and spatial auto‐logistic modelling of the relationship between degradation and land use dynamics in Lam Phra Phloeng watershed of Thailand enabled 80.2% of land to be classified correctly in terms of the presence or absence of erosion and explained 53.2% of the total variation. Cultivation and dependence on agriculture for livelihood positively and significantly affect degradation. Lack of access to institutional credit and land titles significantly increased the probability of occurrence of degradation. On the other hand, education and social cohesion are negatively associated with the occurrence of degradation. The Relative Operating Characteristic (ROC) curve was used to measures the performance of the model. The calculated area under the curve (0.879) suggests that significant predictor variables in the model can be confidently used to forecast the likelihood of occurrence of degradation and thus to identify priority areas for intervention. Policies to reduce land degradation should include measures to reduce pressure on the land, including alternative income sources. Policies could mobilize capital to invest in encouraging nature‐based tourism and other off‐farm income options.  相似文献   
995.
Consistent and relevant information on the status of water systems is indispensable for rational and cost-effective water management. This statement has general validity for all types of river basins, but is particularly relevant for transboundary water regions. Information is used to support decision-making and to evaluate the effects of water resources management decisions. Information production however lags behind developments in water management, which becomes clear from the fact that information still focuses on ecological components of water bodies and largely ignores the importance of socio-economic data stemming from human activities taking place in the river basin. Production of improved information is hindered by strong boundaries between different disciplines that are not easily overcome. Moreover, consideration of information needs and the goals of information dissemination prior to producing information is insufficient and the relevant actors are often reluctant to participate in these processes as they are time consuming. Differences in institutional behaviour also hinder cooperation between institutions, while organisational structures are insufficiently tuned to the needs of the external environment. All these issues hinder the use of information as the basis for decision-making. This paper provides an overview of relevant aspects of information from a broad range of perspectives and establishes the need for changes in the production and use of environmental information in support of water management. The paper is largely based on the outcomes of a closed multi-disciplinary specialist meeting on the role and use of environmental data and information in transboundary water contexts held in Arendal, Norway, September 2002.  相似文献   
996.
997.
Soil organic carbon (SOC) is one of the most important carbon stocks globally and has large potential to affect global climate. Distribution patterns of SOC in Denmark constitute a nation-wide baseline for studies on soil carbon changes (with respect to Kyoto protocol). This paper predicts and maps the geographic distribution of SOC across Denmark using remote sensing (RS), geographic information systems (GISs) and decision-tree modeling (un-pruned and pruned classification trees). Seventeen parameters, i.e. parent material, soil type, landscape type, elevation, slope gradient, slope aspect, mean curvature, plan curvature, profile curvature, flow accumulation, specific catchment area, tangent slope, tangent curvature, steady-state wetness index, Normalized Difference Vegetation Index (NDVI), Normalized Difference Wetness Index (NDWI) and Soil Color Index (SCI) were generated to statistically explain SOC field measurements in the area of interest (Denmark). A large number of tree-based classification models (588) were developed using (i) all of the parameters, (ii) all Digital Elevation Model (DEM) parameters only, (iii) the primary DEM parameters only, (iv), the remote sensing (RS) indices only, (v) selected pairs of parameters, (vi) soil type, parent material and landscape type only, and (vii) the parameters having a high impact on SOC distribution in built pruned trees. The best constructed classification tree models (in the number of three) with the lowest misclassification error (ME) and the lowest number of nodes (N) as well are: (i) the tree (T1) combining all of the parameters (ME = 29.5%; N = 54); (ii) the tree (T2) based on the parent material, soil type and landscape type (ME = 31.5%; N = 14); and (iii) the tree (T3) constructed using parent material, soil type, landscape type, elevation, tangent slope and SCI (ME = 30%; N = 39). The produced SOC maps at 1:50,000 cartographic scale using these trees are highly matching with coincidence values equal to 90.5% (Map T1/Map T2), 95% (Map T1/Map T3) and 91% (Map T2/Map T3). The overall accuracies of these maps once compared with field observations were estimated to be 69.54% (Map T1), 68.87% (Map T2) and 69.41% (Map T3). The proposed tree models are relatively simple, and may be also applied to other areas.  相似文献   
998.
An assessment is made of the atmospheric emissions from the life cycle of fuel ethanol coupled with the cogeneration of electricity from sugarcane in Brazil. The total exergy loss from the most quantitative relevant atmospheric emission substances produced by the life cycle of fuel ethanol is 3.26E+05 kJ/t of C2H5OH. Compared with the chemical exergy of 1 t of ethanol (calculated as 34.56E+06 kJ), the exergy loss from the life cycle's atmospheric emission represents 1.11% of the product's exergy. The activity that most contributes to atmospheric emission chemical exergy losses is the harvesting of sugarcane through the methane emitted in burning. Suggestions for improved environmental quality and greater efficiency of the life cycle of fuel ethanol with cogenerated energy are: harvesting the sugarcane without burning, renewable fuels should be used in tractors, trucks and buses instead of fossil fuel and the transportation of products and input should be logistically optimized.  相似文献   
999.
The release of inorganic and organic contaminants from municipal solid waste incinerator (MSWI) bottom ash is controlled to a large extent by the release of dissolved organic carbon (DOC), and in particular by the reactive humic (HA) and fulvic acids (FA) subfractions of DOC. The properties of organic matter contributing to the release of DOC, HA and FA are, therefore, important for environmental risk assessment. In this study we have quantitatively measured the carbon speciation, and its relation with the leaching of Cu, in three fresh and carbonated MSWI bottom ash samples. Results show that up to only 25% of loss on ignition (LOI) consists of organic carbon (OC), while about 17% of OC in the three samples consists of HA and FA. Up to 50% of DOC in MSWI bottom ash leachates was identified as fulvic acid (FA). This value is substantially higher than previously estimated for these MSWI bottom ash samples and is consistent with the higher recovery of the new method that was applied. The results of this study imply that methods focusing on specific carbon fractions are more appropriate for assessment of environmentally relevant organic carbon species than the measurement of LOI.  相似文献   
1000.
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