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151.
The characterization of urban solid waste generation is fundamental for adequate decision making in the management strategy of urban solid waste in a city. The objective of this study is to characterize the waste generated in the households of Chihuahua city, and to compare the results obtained in areas of the city with three different socioeconomic levels. In order to identify the different socioeconomic trends in waste generation and characterization, 560 samples of solid waste were collected during 1 week from 80 households in Chihuahua and were hand sorted and classified into 15 weighted fractions. The average waste generation in Chihuahua calculated in this study was 0.676 kg per capita per day in April 2006. The main fractions were: organic (48%), paper (16%) and plastic (12%). Results show an increased waste generation associated with the socioeconomic level. The characterization in amount and composition of urban waste is the first step needed for the successful implementation of an integral waste management system.  相似文献   
152.
Air pollution control (APC) residues from waste incineration have been blended with silica and alumina and the mix melted using DC plasma arc technology. The chemical composition of the fully amorphous homogeneous glass formed has been determined. Waste acceptance criteria compliance leach testing demonstrates that the APC residue derived glass releases only trace levels of heavy metals (Pb (<0.007mg/kg) and Zn (0.02mg/kg)) and Cl(-) (0.2mg/kg). These are significantly below the limit values for disposal to inert landfill. It is concluded that plasma treatment of APC residues can produce an inert glass that may have potential to be used either in bulk civil engineering applications or in the production of higher value glass-ceramic products.  相似文献   
153.
Five organic Sloping and Mountainous Olive Plantation Production Systems (SMOPS) have been studied in four olive-producing areas in four European countries (Spain, Italy, Greece and Portugal). Results indicate that these SMOPS provide ecological, economic and social benefits to the regions in which they are located, although most of these benefits are not strictly limited to the organic production systems. Erosion control and organic matter balance remain significant issues in four of the SMOPS and we suggest that subsidy support should be conditional on the implementation of additional soil and water conservation measures that should be provided with specific funding. Most of the SMOPS will remain dependent on a similar level of support in order for olive production to remain economically feasible. The lower profitability compared to non-organic olive production systems suggests that there is limited scope for expansion of organic olive production, although in the study areas where there is little such production, such as Western Crete (Greece) and Basilicata-Salerno (Italy) the scope remains great. The analysis of the reasons for the beneficial effects of olive cultivation in the areas studied indicates that in most cases soil management techniques adopted in or recommended for organic production systems could provide similar benefits in other production systems as well.  相似文献   
154.
This article describes the collaborative modeling process and the resulting water resources planning model developed to evaluate water management scenarios in the transboundary Rio Grande basin. The Rio Grande is a severely water stressed basin that faces numerous management challenges as it crosses numerous jurisdictional boundaries. A collaborative process was undertaken to identify and model water management scenarios to improve water supply for stakeholders, the environment, and international obligations of water delivery from Mexico to the United States. A transparent and open process of data collection, model building, and scenario development was completed by a project steering committee composed of university, nongovernmental, and governmental experts from both countries. The outcome of the process was a planning model described in this article, with data and operations that were agreed on by water planning officials in each country. Water management scenarios were created from stakeholder input and were modeled and evaluated for effectiveness with the planning model.  相似文献   
155.
Samples of the slime mold Fuligo septica (L.) Wiggers were collected from an ecologically diverse selection of sites across the former USSR and in North Korea to determine their Zn concentrations. Plasmodia were collected from trees, rocks, soils, the walls of buildings and a variety of other materials and structures from 1990 to 1996. The biomass collected ranged from 305 to 968 mg, whereas Zn concentrations in plasmodia of F. septica ranged from 8400 to 23,000 mg kg(-1) dry wt. (mean and standard error = 14,200 +/- 860 mg kg(-1) dry wt.). No clear trend as to which areas produced F. septica with the highest Zn concentrations was discernable. Nor was it possible to identify any particular substrate on which F. septica grew that produced noticeably high Zn concentrations. For example, forest litter on which F. septica was found had Zn concentrations of only 25 to 130 mg kg(-1) dry wt. Our data confirm the only other study showing hyperaccumulation of Zn in F. septica, which was carried out in Finland. This ability seems to be unique to this species, but how or why it does this, or why such high Zn concentrations are not toxic to F. septica, are questions requiring future research.  相似文献   
156.
Sulphur migration in the soil-plant system was studied in a field experiment carried out in the spruce-pine forest 70 km SE from the 'Severonickel' smelting plant on the Kola Peninsula. In the experiment, dry particle deposits collected from filters of smokestacks in different departments of 'Severonickel' were applied on the study plots and on gravity lysimeters in quantities simulating estimated actual annual emissions in the area within 2-5 km from the smelter. In the present paper, the effects of two types of deposits consisting mostly of water-soluble sulphates of copper and nickel are described ("Cu-contaminant": Cu-55%, Ni-3.8%, SO4-25%; "Ni-contaminant": Ni-20%, Cu-5%, SO4--65%). Soil, plant tissue and penetration water were analysed during 3 years after the treatment. Extractable sulphur distribution in the soil-plant system showed downward movement after 1 year and upward movement after 3 years. The trend was more pronounced in the site treated with Ni-contaminant.  相似文献   
157.
The surveillance of communicable diseases after a natural disaster reflects the permanent state of effectiveness of the health services and the adverse factors of the natural, physical and family environments. Diarrhoeal diseases may be the best indicator of a community's period of recovery. The return of these diseases to endemic levels means that the pre-disaster situation has been reestablished.  相似文献   
158.
This study was carried out in 32 communities neighbouring four Ramsar wetlands in Northern Greece. In particular, it concerns the study of local residents' attitude regarding the ways of management and exploitation of the wetlands and their sociological features, using the opinion poll method (1600 questionnaires were distributed). The aim of this investigation is the evaluation of findings for planning of effective management and conservation policy of wetlands, incorporating the opinions of local residents. Further protection of the wetlands, awareness of local residents of the value of wetlands, tourism or agriculture development (in some cases), as well as more governmental support, became obvious results from this research.  相似文献   
159.
160.
Workers (n = 17 275) from 14 European Union (EU) member states provided data on job control, job dissatisfaction, perceived risk of occupational stress, and absence. For each state, level of research and development (R&D) activity was assessed. Associations between individual levels of control and occupational health were stronger where national R&D activity was higher. The moderation occurred for individuals' levels of control in relation to job dissatisfaction, perceived risk of occupational stress, and absence. The findings with job dissatisfaction and absence were replicated in a sample of workers from 10 Eastern European former Communist countries (n = 7926). Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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