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This paper presents the story of a project undertaken by researchers who are active participants in the national Australian debate over place and belonging. It arose from the desire to ground this debate, which brings issues of ecological sustainability, reconciliation and multiculturalism together, in more localised action aimed at building a 'place-responsive society'. The project was carried out as a case study in a region that combines part of the Sydney metropolitan area and the separate 'city' of the Blue Mountains, and involved a consultative committee and then a regional forum of conservationists, environmental educators and community workers. The researchers explored existing place-oriented initiatives in the region and developed practical projects for the future, most notably a proposal for 'totemic species' work within schools involving local Aboriginal people. The research demonstrated, more than anything else, that indigenous Australian approaches to 'place awareness' and nature conservation remain highly relevant in contemporary Australia. It also showed that bioregional awareness and the notion of place responsiveness can add value to more traditional approaches to nature conservation and environmental education. There are opportunities to galvanise local action that can integrate community and environmental work and revitalise professional practice in both areas, but the effort involves working constantly with difference and conflict.  相似文献   
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In this study we evaluated the effect of different fertilizer treatments on Brassica plants grown on boron-contaminated sediments. Experiments were conducted in the laboratory and on the lysimeter scale. At laboratory scale (microcosm), five different fertilizers were tested for a 35-d period. On the lysimeter scale, nitrogen fertilization was tested at three different doses and plants were allowed to grow until the end of the vegetative phase (70 d). Results showed that nitrogen application had effectively increased plant biomass production, while B uptake was not affected. Total B phytoextracted increased three-fold when the highest nitrogen dose was applied. Phytotoxicity on Brassica was evaluated by biochemical parameters. In plants grown in unfertilized B-contaminated sediments, the activity of antioxidant enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and pyrogallol peroxidase (PPX) increased, whereas catalase (CAT) decreased with respect to control plants. Addition of N progressively mitigated the alteration of enzymatic activity, thus suggesting that N can aid in alleviating B-induced oxidative stress. SOD activity was restored to control levels just at the lowest N treatment, whereas the CAT inhibition was partially restored only at the highest one. N application also lowered the B-induced increase in APX and PPX activities. Increased glutathione reductase activity indicated the need to restore the oxidative balance of glutathione. Data also suggest a role of glutathione and phytochelatins in B defense mechanisms. Results suggest that the nitrogen fertilizer was effective in improving B phytoextraction by increasing Brassica biomass and by alleviating B-induced oxidative stress.  相似文献   
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The objective of the present study was to monitor the levels of organochlorine pesticides HCB; α-, β-, γ-HCH; pp'DDE; op'DDT; and pp'DDT in blood serum of Veracruz, Mexico inhabitants. Organochlorine pesticides were analyzed in 150 blood serum samples that constituted that which remained after clinical analyses, using gas chromatography-electron-capture detection (GC-ECD). The results were expressed as milligrams per kilogram on fat basis and micrograms per liter on wet weight. Only the following pesticides were detected: p,p'-DDE was the major organochlorine component, detected in 100% of samples at mean 15.8 mg/kg and 8.4 μg/L; p,p'-DDT was presented in 41.3.% of monitored samples at mean 3.1 mg/kg and 1.4 μg/L; β-HCH was found in 48.6% of the samples at mean 4.9 mg/kg and 2.7 μg/L; op'DDT was determined to be in only 3.3% of monitored samples at mean 2.7 mg/kg and 1.4 μg/L. The pooled samples divided according to sex showed significant differences of β-HCH and pp'DDE concentrations in females. The samples grouped according to age presented the third tertile as more contaminated in both sexes, indicating age as a positively associated factor with serum organochlorine pesticide levels in Veracruz inhabitants.  相似文献   
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High-resolution gamma spectrometry was used to determine the concentration of 40K, 238U and 232Th series in soil samples taken from areas surrounding the city of Aldama, in Chihuahua. Results of indoor air short-time sampling, with diffusion barrier charcoal detectors, revealed relatively high indoor radon levels, ranging from 29 to 422 Bq/m3; the radon concentrations detected exceeded 148 Bq/m3 in 76% of the homes tested. Additionally, liquid scintillation counting showed concentrations of radon in drinking water ranging from 4.3 to 42 kBq/m3. The high activity of 238U in soil found in some places may be a result of the uranium milling process performed 20 years ago in the area. High radon concentrations indoor and in water may be explained by assuming the presence of uranium-bearing rocks underneath of the city, similar to a felsic dike located near Aldama. The estimated annual effective dose of gamma radiation from the soil and radon inhalation was 3.83 mSv.  相似文献   
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Air pollution, harvesting practices, and natural disturbances can affect the growth of trees and forest development. To make predictions about anthropogenic impacts on forests, we need to understand how these factors affect tree growth. In this study the effect of disturbance history on tree growth and stand structure was examined by using a computer model of forest development. The model was run under the climatic conditions of east Tennessee, USA, and the results compared to stand structure and tree growth data from a yellow poplar-white oak forest. Basal area growth and forest biomass were more accurately projected when rough approximations of the thinning and fire history typical of the measured plots were included in the simulation model. Stand history can influence tree growth rates and forest structure and should be included in any attempt to assess forest impacts.  相似文献   
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Different ways for modeling the impact of vehicle emission inspection and maintenance programs on fleet hydrocarbon emissions are examined. A dynamic model is developed for forecasting fleet emissions in which individual vehicle performance is modeled as a stochastic process and vehicle emissions are tracked over time. Emissions inspection and repair are incorporated into the model, allowing for the stochastic aspects of both testing and repair. This model is compared to EPA’s model for evaluating the impact of vehicle emissions inspection and maintenance. We find that the way vehicle emission equipment deterioration overtime is modeled is important for forecasting emissions from the fleet and for assessing the success of inspection and maintenance programs. For inspection programs, we find that factors such as the proportion of vehicles tested, and repair effectiveness and duration have the greatest impact on emission reductions. The ability of different emission testing regimes to identify polluting vehicles has less impact on a program’s overall potential for emissions reduction. Policy recommendations for I&M testing and predictions of emission reduction credits from these tests will depend in important ways on the methods used in the underlying emissions models.  相似文献   
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