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排序方式: 共有1086条查询结果,搜索用时 31 毫秒
31.
Jennifer H. Westerman James W. Westerman Brian G. Whitaker 《Environment, Development and Sustainability》2016,18(2):561-576
Recent conjecture on the potential primacy of physical environmental components in education for sustainable development (ESD) efforts serves to question the centrality of social justice education as a component of ESD. This research explores a sustainable development student’s basic knowledge of social justice conditions in their country of residence and its relationships to policy attitudes that should be of importance to ESD, including beliefs about the importance of corporate social responsibility, their endorsement of gross national product as an effective measure of progress, their overall assessment of the social fairness of current national social justice policy, and their endorsement of the goals of Occupy Wall Street. Results obtained using path-model hypothesis testing indicate that accuracy of knowledge of US standing on social justice issues is significantly related to these policy attitudes, providing support for social justice content in ESD endeavors to create students empowered for engagement in broader policy goals. 相似文献
32.
This paper evaluates risk factors that influence the probability that a house will burn from wildfire. A logistic regression is used to analyse data processed from pre-fire and post-fire IKONOS images and other geo-referenced data. The dependent variable is the probability that a given house will burn. A total of 12 independent variables are evaluated: vegetation density; area of defensible space; adjacency of a parcel to public lands; proximity of a house to fire station; road width; road type; parcel size; subdivision morphology; assessed value; elevation; slope and aspect. Model results generally support dominant land use planning and design strategies for wildfire risk reduction including vegetation treatments, site selection with respect to topography, and improving access to fire stations. 相似文献
33.
Anna Rabinovich Thomas A. Morton Tom Postmes Bas Verplanken 《Journal of environmental psychology》2009
This paper investigated the effect of goal and mindset specificity on goal-related behavior in the environmental domain. Two studies demonstrated that goal-related behavior was maximized when participants focused on an abstract goal in combination with a specific mindset, or when they focused on a specific goal in combination with an abstract mindset. When goals and mindsets instead matched in terms of abstractness, goal-related behavior was reduced. Study 2 demonstrated that the effect of goal specificity on behavior was mediated by different processes in each of the mindset conditions. When mindsets were abstract, self-efficacy mediated the positive effect of specific goals on behavior; when mindsets were specific, the value of collective environmental action mediated the positive effect of abstract goals on behavior. The results are discussed in the framework of a complementarity approach. It is argued that complementarity of levels of specificity of goals and mindsets may affect behavior particularly strongly in domains where the discrepancy between the abstract and the specific is large (e.g. the environmental domain). 相似文献
34.
Kelley L. Arbogast Brian C.P. Kane Jeffrey L. Kirwan Bradley R. Hertel 《Journal of environmental psychology》2009
Empirical and anecdotal evidence suggests that landscapes with more vegetation have a positive impact on children's focus, attention, and cognitive development. In school, children are able to regain focus, suppress impulses, and pay attention in class longer after exposure to natural settings. Because children spend much of their time in school, the amount and types of vegetation on school grounds may influence their development. Public elementary schools in the Commonwealth of Virginia (N = 988) were surveyed to examine correlations between school ground vegetation and outside recess. The number of trees on school grounds, the size of the school grounds, and the presence of sports fields were modestly correlated with greater outside recess time. These correlations support common sense because sports fields facilitate supervised play and larger school grounds provide space for sports fields and playgrounds and additional opportunities for free play. More trees on school grounds provide a welcoming environment for students and teachers, and encourage outside play. These results may help school personnel design and maintain school grounds that increase outdoor recess time. 相似文献
35.
Charles A. Young Marisa I. Escobar‐Arias Martha Fernandes Brian Joyce Michael Kiparsky Jeffrey F. Mount Vishal K. Mehta David Purkey Joshua H. Viers David Yates 《Journal of the American Water Resources Association》2009,45(6):1409-1423
Young, Charles A., Marisa I. Escobar‐Arias, Martha Fernandes, Brian Joyce, Michael Kiparsky, Jeffrey F. Mount, Vishal K. Mehta, David Purkey, Joshua H. Viers, and David Yates, 2009. Modeling the Hydrology of Climate Change in California’s Sierra Nevada for Subwatershed Scale Adaptation. Journal of the American Water Resources Association (JAWRA) 45(6):1409‐1423. Abstract: The rainfall‐runoff model presented in this study represents the hydrology of 15 major watersheds of the Sierra Nevada in California as the backbone of a planning tool for water resources analysis including climate change studies. Our model implementation documents potential changes in hydrologic metrics such as snowpack and the initiation of snowmelt at a finer resolution than previous studies, in accordance with the needs of watershed‐level planning decisions. Calibration was performed with a sequence of steps focusing sequentially on parameters of land cover, snow accumulation and melt, and water capacity and hydraulic conductivity of soil horizons. An assessment of the calibrated streamflows using goodness of fit statistics indicate that the model robustly represents major features of weekly average flows of the historical 1980‐2001 time series. Runs of the model for climate warming scenarios with fixed increases of 2°C, 4°C, and 6°C for the spatial domain were used to analyze changes in snow accumulation and runoff timing. The results indicated a reduction in snowmelt volume that was largest in the 1,750‐2,750 m elevation range. In addition, the runoff center of mass shifted to earlier dates and this shift was non‐uniformly distributed throughout the Sierra Nevada. Because the hydrologic model presented here is nested within a water resources planning system, future research can focus on the management and adaptation of the water resources system in the context of climate change. 相似文献
36.
37.
Refaul Ferdous Faisal Khan Rehan Sadiq Paul Amyotte Brian Veitch 《Process Safety and Environmental Protection》2009,87(5):283-292
Event tree analysis (ETA) is an established risk analysis technique to assess likelihood (in a probabilistic context) of an accident. The objective data available to estimate the likelihood is often missing (or sparse), and even if available, is subject to incompleteness (partial ignorance) and imprecision (vagueness). Without addressing incompleteness and imprecision in the available data, ETA and subsequent risk analysis give a false impression of precision and correctness that undermines the overall credibility of the process. This paper explores two approaches to address data uncertainties, namely, fuzzy sets and evidence theory, and compares the results with Monte Carlo simulations. A fuzzy-based approach is used for handling imprecision and subjectivity, whereas evidence theory is used for handling inconsistent, incomplete and conflicting data. Application of these approaches in ETA is demonstrated using the example of an LPG release near a processing facility. 相似文献
38.
Acid mine drainage and metal loads from hardrock mines to surface waters is a significant problem in the western USA and many parts of the world. Mines often occur in mountain environments with fractured bedrock aquifers that serve as pathways for metals transport to streams. This study evaluates impacts from current and potential future groundwater metal (Cd, Cu, and Zn) loads from fractures underlying the Gilt Edge Mine, South Dakota, on concentrations in Strawberry Creek using existing flow and water quality data and simple mixing/dilution mass balance models. Results showed that metal loads from bedrock fractures to the creek currently contribute <1% of total loads. Even if background water quality is achieved upstream in Strawberry Creek, fracture metal loads would be <5%. Fracture loads could increase substantially and cause stream water quality standards exceedances once groundwater with elevated metals concentrations in the aquifer matrix migrates to the fractures and discharges to the stream. Potential future metal loads from an upstream fracture would contribute a small proportion of the total load relative to current loads in the stream. Cd has the highest stream concentrations relative to standards. Even if all stream water was treated to remove 90% of the Cd, the standard would still not be achieved. At a fracture farther downstream, the Cd standard can only be met if the upstream water is treated achieving a 90% reduction in Cd concentrations and the median stream flow is maintained. 相似文献
39.
The results from the multimillion dollar Enrichment of Nutrients on Coral Reefs Experiment (ENCORE) on One Tree Island Reef (OTIR) suggest that increased nutrient loads to coral reefs will have little or no effect on the algal growth rates and, hence, on the associated effects that increased algal growth might have on the functioning and stability of coral reefs. However, a comparison of the concentrations of nutrients within the OTIR lagoon with the proposed nutrient threshold concentrations (NTC) for coral reefs suggests that all sites, including the control sites, were saturated with nutrients during ENCORE, and, hence, one would not expect to get any differences between treatments in the algal-growth related measurements. Thus, ENCORE results provide strong support for the proposed NTCs and support the ecological principle that algal productivity and, consequently, the functioning of coral reefs are sensitive to small changes in the background concentrations of nutrients. The principal conclusion of ENCORE, namely that the addition of nutrients did not cause the "pristine" OTIR to convert from coral communities to algal dominated reefs, is contrary to the fact that there was prolific macroalgal growth on the walls and crests of the experimental microatolls by the end of ENCORE. 相似文献
40.
Reductive hydrogenation of polycyclic aromatic hydrocarbons catalyzed by metalloporphyrins 总被引:2,自引:0,他引:2
The hydrogenation of polycyclic aromatic hydrocarbons (PAHs) (naphthalene, anthracene, and phenanthrene) catalyzed by metalloporphyrins based on cobalt, nickel or iron was studied in aqueous solutions at room temperature and ambient pressure. Nickel porphyrin (P1) activated by nanosized zero-valent iron (nano-ZVI) and cobalt porphyrins (P2) and (P4) activated by titanium(III) citrate as the electron donor were demonstrated to be promising catalysts for the reductive hydrogenation of PAHs. In particular, partially saturated di-, tetra-, and octahydrogenated products were obtained for anthracene or phenanthrene using a nickel porphyrin activated by nano-ZVI, while naphthalene was transformed to tetralin. Systems containing cobalt porphyrins activated by titanium(III) citrate exhibited a high selectivity and activity toward hydrogenation of anthracene, producing 9,10-dihydroanthracene. However, no formation of hydrogenated hydrocarbons was observed from naphthalene or phenanthrene using cobalt porphyrins. 相似文献