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971.
972.
本文简要介绍了无铅汽油添加剂MTBE的物理化学性质、环境化学行为、地下水的污染状况和对动物的潜在致癌毒理 ,并对其分析方法作了综述 ,指出了我国开展MTBE有关研究的重要性。 相似文献
973.
The impact of direct and indirect experiences on the development of environmental knowledge, attitudes, and behavior 总被引:2,自引:0,他引:2
This study employed a mixed-methods design to examine the relationship between nature experience type (e.g., direct and indirect) and learning outcomes (e.g., environmental knowledge, attitudes, and behavior) associated with an environmental education, international immersion program for adolescents. Longitudinal data from 108 participant and 49 comparison group members were analyzed to test the study’s hypotheses. Additionally, qualitative data were analyzed using grounded theory methodology to assess participants’ perceptions of these processes. The findings indicate that environmental knowledge increased more than environmental attitudes during the indirect portion of the program (i.e., preparatory program) whereas the direct portion (i.e., international workshop) produced similar levels of knowledge and attitude growth. Further, while attitudes were more strongly associated with behavior during the indirect component of the program, the strength of the relationships between attitudes and behavior, and knowledge and behavior were similar during the direct portion of the experience. A synthesis of the findings suggests that the program’s direct experiences catalyzed environmental knowledge into a stronger motivating force than it had been during the indirect experiences. The qualitative findings also provide insights into the characteristics of direct experiences. These findings offer important insights for both theory and practice related to the use of direct and indirect nature experiences to develop environmental knowledge, attitude, and behaviors. 相似文献
974.
Benjalak Karnchanasest Darryl W. Hawker 《Journal of environmental science and health. Part. B》2013,48(5):411-418
Amphiphilic nonionic cross-linked nanopolymers (NPs) were synthesized to examine removal of five organochlorines (OCs), namely lindane, heptachlor, aldrin, dieldrin, endrin, and DDT, from a range of Thai agricultural soils. The synthesized NP particles had polarity characteristics similar to those of nonionic surfactant micelles and were largely in the size range of 55–155 nm. This work aimed to determine the optimal conditions for leaching of OC contaminated soil with NPs and also to investigate the role and influence of soil properties on this leaching. An investigation of the concentrations of aqueous dispersions of these particles found that a concentration of 10 g L?1. was found most effective in leaching the OCs from a column of spiked soil. The optimal contact time that allowed a NP dispersion and spiked soil to reach equilibrium was 48 h. The results indicated influencing factors for OC removal and soil remediation were properties both of the soil and the compounds themselves. Soil organic carbon (SOC) content and soil texture played an important role on the sorption as well as compound hydrophobicity expressed as log KOW values. The removal efficiency was found to be in the range of 85.2–92.8 % for all soil samples and in the order of DDT < aldrin < heptachlor < dieldrin < endrin < lindane regardless of soil type. This order is inversely related to the log KOC values of these compounds. For OC compounds with a similar molecular structure, removal efficiency was related to molecular weight (MW). 相似文献
975.
Stacy A. Lischka Tara L. Teel Heather E. Johnson Courtney Larson Stewart Breck Kevin Crooks 《Conservation biology》2020,34(6):1383-1392
Conflicts between people and wild animals are increasing globally, often with serious consequences for both. Local regulations or ordinances are frequently used to promote human behaviors that minimize these conflicts (risk-reducing behaviors), but compliance with ordinances can be highly variable. While efforts to increase compliance could be improved through applications of conservation psychology, little is known about the relative influence of different factors motivating compliance. Using concepts from psychology and risk theory, we conducted a longitudinal study pairing data from mail surveys with direct observations of compliance with a wildlife ordinance requiring residents to secure residential garbage from black bears (Ursus americanus). We assessed the relative influence of beliefs and attitudes toward bears and bear proofing, perceived behavioral control, perceived risks and benefits assigned to bears, norms, trust in management, previous experience with conflicts, and demographics on compliance behavior (i.e., bear proofing). Data on previous experience were obtained through direct observation and survey reports. We found that higher compliance rates were associated with more observed conflicts on a respondent's block. Counter to expectations, however, residents were less compliant when they were more trusting of the management agency and perceived more benefits from bears. We suggest that messages have the potential to increase compliance when they empower residents by linking successful management of conflicts to individual actions and emphasize how reducing conflicts could maintain benefits provided by wildlife. Modifying existing educational materials to account for these psychological considerations and evaluating their impact on compliance behavior over time are important next steps in changing human behaviors relevant to the globally important problem of human-wildlife conflict. 相似文献
976.
公众参与环保行为影响因素的实证研究 总被引:7,自引:0,他引:7
王凤 《中国人口.资源与环境》2008,18(6)
依据环境意识和社会背景对环保行为的交互作用机理,采用2006年横截面数据对陕西公众环保行为的现状和影响因素分别进行了实证检验.回归分析发现公众陈述的环保行为整体得分尚不及格,但较1998年的全国平均得分有大幅提高;环保重要性、环保知识、受教育程度对个人环保习惯和公共环保行为的影响呈显著正相关;性别差异在个人环保习惯中表现突出,在公共环保行为中并不显著;收入、年龄、环保意义变量的影响都不显著.从个人环保习惯路径分析模型发现环保重要性是最显著的中介变量.最后,文章建议政府应该通过提高公众的环保重要性意识,并进一步提高他们的受教育程度和环保知识水平,且以女性为突破口来带动更广泛意义上的公众参与环保行为 相似文献
977.
Global demand for elephant ivory is contributing to illegal poaching and significant decline of African elephant (Loxondonta africana) populations. To help mitigate decline, countries with legal domestic ivory markets were recommended by the Convention on International Trade in Endangered Species of Wild Fauna and Flora to close domestic markets for commercial trade. However, implementing stricter regulations on wildlife trade does not necessarily mean compliance with rules will follow. Using an online questionnaire, we examined the relationship between self-reported compliance with ivory trade regulations among 115 ivory traders in the United Kingdom and 4 dimensions (control, deterrence, legitimacy, and social norms) hypothesized to influence compliance with conservation regulations. Although most traders supported regulations, a large number did not always check that they comply with them when trading objects containing ivory. The main factors influencing compliance with ivory trade regulations were traders’ ability to comply and their perceptions of the regulations and punishments to deter illegal trade. These findings demonstrate the utility of conservation criminology to improve wildlife trade regulations and identify opportunities to reduce illegal ivory entering the market in the United Kingdom. Compliance could be improved by clearer regulations that facilitate easier detection of illegal ivory products and stronger prosecution of violations. 相似文献
978.
Many simulations of collective behavior have been presented in recent years. Recently, a pioneering study by
[Ballerini et al., 2008a] and [Ballerini et al., 2008b] suggested that the interactions of birds in a flock should be modeled using the topological distance rather than the metric distance. The concept of topological distance is deemed important for explaining collective behavior. However, few studies have discussed the distinctions between the metric and topological distances. In this paper, we clarify the difference between models based on the topological and metric distances and propose a new hybrid model of these models. The agent of our model switches between these two interactions by tuning the threshold parameters. We show that this hybrid flocking model has the medium property between the metric and the topological distance. In other words, the agents of our hybrid model can dramatically make and divide flock by tuning their neighborhoods. This result suggests that making and dividing flock would be deeply connected with animal's cognition. 相似文献
979.
Abstract With the income increase of elderly people in Beijing and the improvement of leisure facilities since 2000, the quality of elderly people leisure life in Beijing has obviously increased compared to ten years ago. According to the investigation and comparative analysis on more than 900 elderly people, who usually exercise in public parks in Beijing City, we have found out several new features of elderly people’s outdoor recreation in Beijing: the increase of the leisure time, the expansion of leisure space, the individuation of interest and the diversification of consumption. The leisure life quality evaluation index system of urban elderly people can be built based on these analyses. In order to accommodate the development tendency of elderly people’s demand for leisure diversification, we should strengthen the organization and management of elderly people’s leisure activity in urban construction, and pay more attention to function complementation between communities and parks. 相似文献
980.
驾驶中使用手机与交通事故之间存在着高度相关性。为揭示使用手机对驾驶行为安全绩效的影响,探索影响驾驶安全的理论机制,采取更有效的干预措施,结合近10 a来相关研究,综述了与驾驶安全密切相关的驾驶分心问题,主要包括:驾驶员分心的定义及其分类;使用手机对驾驶行为安全绩效的影响,如反应时(RT)、行车速度、路线保持和跟车距离;手机使用对驾驶员分心影响的理论机制,如信息加工理论和计划行为理论(TPB)。分析表明,使用手机会导致驾驶员的反应时延长15%~40%,驾驶路线发生明显偏移,对于行车速度减缓和跟车距离延长的假设需结合驾驶员主客观数据进行比较做进一步验证;驾驶过程中使用手机会增加驾驶员的认知负荷,TPB能够对使用手机行为进行有效的解释和预测,但对该理论中基于信念测量的研究还很少;除手机操作任务,影响驾驶员分心的其他操作任务还需做进一步的研究。 相似文献