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41.
/ This study examines similarities and differences between organic and conventional farmers. We explore the factors that underlie farmers' conservation attitudes and behaviors, including demographic and farm characteristics, awareness of and concern for environmental problems associated with agriculture, economic orientation toward farming, and self-reported conservation practices. A series of intensive personal interviews was conducted with 25 farmers in Washtenaw County, Michigan, USA, using both qualitative and quantitative survey methods. The findings indicate that both groups of farmers share a concern for the economic risks associated with farming, although the organic farmers reported a significantly greater concern for long-term sustainability and a greater willingness to incur present risk to gain future benefits. Organic farmers expressed a greater awareness of and concern for environmental problems associated with agriculture. Organic farmers also scored significantly higher on a multifaceted measure of conservation practices, although both groups had a fairly high adoption rate. Implications of these findings are discussed, relative to economic risks of farming, implications for new farmers, effectiveness of conservation education and government programs, and impact of farm size and crop diversity.KEY WORDS: Environmental attitudes; Conservation behaviors; Organic farming; Agricultural sustainability  相似文献   
42.
Animal wastes from intensive farming are generally collected for field fertilisation. They may contain drugs that can become soil pollutants. To evaluate the possible effects of such contamination in terrestrial systems, sulphadimethoxine has been subjected to laboratory tests (in vitro, synthetic medium, and soil) using seeds of barley (Hordeum distichum L.). The drug suppressed normal post-germinative development and growth of roots and leaves in both test conditions; this effect was dependent on the bioaccumulation rate, which was higher on synthetic medium than in soil. Bioaccumulation was higher in roots than foliage and this was markedly evident in soil and, in particular, in soils with a low humus content. The environmental risk of sludge application on soils and the possible contamination of food chains are discussed.  相似文献   
43.
In recent years, churches across the world have become involved in dialogue on the theory and practice of sustainable development. A number of Western churches have expressed their concern about climate change and destructive living patterns, stressing the need for human beings to exercise the care for all creation based on a life of sharing and sacrifice. Some Orthodox churches, however, quite recently included the environmental issues in their agendas. While the Bases of Social Concept, a major doctrine of the Russian Orthodox Church adopted in 2000, for the first time emphasises the Churchs position in overcoming environmental crisis and presents a solid basis on which to build the future environmental strategy of the Church, the Ethiopian Orthodox Church has not yet drawn up a programme document that might serve as a framework for the Churchs current extensive activities in the field of biodiversity conservation and sustainable forestry practices. Hence, despite certain closeness of both institutions, there is the potential for strengthening their roles in promoting sustainable development, based on the Biblical concept that the Earth belongs to the Lord and humans are responsible stewards assigned the duty to work for creation and care for it. This paper seeks to demonstrate by means of comparable analysis between the two Churches, Orthodox in nature but different in rites and religious practices, that traditional, highly conservative faiths may serve as powerful instruments of spreading out the ideas of sustainable development as the basis of spiritual revival in the situation of the two concurrent and interrelated crises – spiritual and ecological.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
44.
Food production has to be increased in a sustainable way to meet the future global demand. A key position is attributed to developing countries. A deepened understanding of their agricultural regions with specific resource endowments and constraints is therefore crucial. In this study we propose a methodology based on material flux analysis (MFA) to assess the resource potentials and limitations of a Nicaraguan agricultural region. We focus on current regional and farm resource management and explore them under two scenarios. Indicators are nitrogen and the degrees of self-sufficiency (DSS) for energy, and the staples maize and beans. As data is scarce, most information is based on interviews with farmers of four categories and key persons, and on literature. The results show that nitrogen management does not differ considerably among categories. Nitrogen is mined mostly from staple plots. Self-sufficiency for beans is given in an average year. Yet, landless and small farmers neither produce enough maize for autoconsumption, nor are they self-sufficient for firewood. Energy supply is also the core problem of the region, since the DSS is 70%. Soil nitrogen stocks last at most for three more generations. Analyses with the scenario technique show that: (a) Unlimited population growth has serious consequences in the near future e.g. severe shortage of energy and food. (b) Alternative farming systems are possible, but they require reducing the population by a factor 2, and thus the creation of jobs in a Hinterland. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
45.
PROBLEM: After decreasing to a historic low in 1997, motorcycle crash-related fatalities are increasing. Although causes remain unclear, motorcycle rider education and licensing play key roles in reducing motorcycle crashes and injuries. Yet, little is known about what constitutes effective rider training and licensing. This study develops a model of best practices in motorcycle rider education and licensing and combines primary and secondary data to identify states that most closely adhere to this model. Evidence on the validity of the model is also examined. METHOD: States were rated along three areas of best practices: (a) program administration; (b) rider education; and (c) licensing based on 2001 data collected for a National Highway Traffic Safety Administration (NHTSA)-sponsored study. RESULTS: Results indicate wide variation in states' adherence to best practices; several states meet most, others very few. When the areas of best practices are considered separately, a state tends to behave similarly on all three. Initial evidence supports the validity of the model, with high best practices states having the lowest rates of motorcycle fatalities. IMPACT ON TRAFFIC SAFETY: As motorcycle-related crashes increase and state and federal support for rider education programs diminishes, it is critical that states identify deficiencies in their program and learn from successful states about efficient, cost-effective strategies for increasing best practices in motorcycle rider education and licensing.  相似文献   
46.
The rise of social media radically broadens the sources and platforms used for environmental communication. Especially personal green blogs are worthy of study as they are spaces of everyday cultural politics through which people make sense of sustainability issues, and because they entail a radical break from conventional media in terms of legitimacy, form, and content of environmental communication processes. This paper studies the representation of sustainability on personal green blogs, and the communication processes through which these representations are constructed. It does so through a qualitative study of Swedish-language blogs. We study three blogs in-depth: a living experiment blog on sustainable food practices; a lifestyle blog centered around green family life; and a blog about consuming green beauty products. The analysis shows that all three blogs translate the complex landscape of sustainability to individual everyday practices. Yet, what these sustainability practices entail differs considerably between the blogs, ranging from a-political and doable lifestyle choices to an onset to radical redefining of consumption. Also, the communication processes on the blogs differ in quality and quantity. The paper uses these insights to reflect on the debates about how environmental communication is shaped by blogging and social media practices.  相似文献   
47.
Empirical evidence from many regions suggests that most species would be least negatively affected if human food demand were met through high-yield agricultural production and conservation of nonfarm ecosystems (land sparing), rather than through wildlife-friendly farming over a larger area (land sharing). However, repeated glaciation and a long history of agriculture may lead to different results in regions such as western Europe. We compared the consequences of land sparing and land sharing on breeding bird species in 2 lowland regions of England, The Fens, with 101 species, and Salisbury Plain, with 83. We derived density–yield responses for each species and then estimated regional population size under regional food production strategies, including land sharing and land sparing, a range of intermediate strategies, and a novel mixed strategy. In both regions, more species achieved maximum regional population size under land sparing than land sharing. In The Fens, the majority of birds were loser species (estimated to have smaller populations under all food production strategies than in the preagricultural baseline scenario), whereas in Salisbury Plain the majority were winners (smaller populations in the preagricultural baseline scenario). Loser species overwhelmingly achieved maximum regional population size under land sparing, whereas winner species achieved maximum regional population size under either land sharing or an intermediate strategy, highlighting the importance of defining which groups of species are the target of conservation. A novel 3-compartment strategy (combining high-yield farming, natural habitat, and low-yield farming) often performed better than either land sharing or land sparing. Our results support intermediate or 3-compartment land-sparing strategies to maximize bird populations across lowland agricultural landscapes. To deliver conservation outcomes, any shift toward land sparing must, however, ensure yield increases are sustainable in the long term, do not entail increased negative effects on surrounding areas, and are linked to allocation of land for nature.  相似文献   
48.
成都平原蔬菜生产中灌溉水对农药渗漏的影响研究   总被引:9,自引:0,他引:9  
针对成都平原蔬菜生产中大量施用农药、大量灌水的特点,首次在国内应用欧洲官方成熟的农药评估模型——PEARL模型,研究评估了成都平原当前蔬菜生产中的灌溉方式对两种不同特性农药的渗漏的影响。杀毒矾(土壤吸附力(KOM)为0 L/kg,半衰期(DT50)为80 d)在没有灌溉条件下,其渗出土体时的最大质量浓度是190μg.L-1,而有灌溉条件下其渗出质量浓度则可达523μg.L-1,是没有灌溉条件下的2.75倍。三唑磷(KOM为200 L.kg-1,DT50为60 d)在没有灌溉条件下,其渗出土体时的最大质量浓度是0.025μg.L-1,而有灌溉条件下其渗出质量浓度为0.13μg.L-1,比没有灌溉时提高了4.2倍。不管有没有灌溉三唑磷在该地区对地下水的污染风险都很小,而杀毒矾的风险则很高。因此,农药的化学特性是影响农药渗漏的最重要的因子。在蔬菜生产中应尽量选用被土壤吸附力强、半衰期短的农药,例如:三唑磷;农药在土壤中的移动载体是土壤水,不合理的灌溉会大大地加大农药淋溶,应当多使用微喷、滴灌等节水灌溉措施,减少使用漫灌等耗水多的原始灌溉方式。  相似文献   
49.
本文在比较全面、系统地总结改革开放15年来,南方稻田耕作制度调整与改革所取得的成效的基础上,指出了目前南方稻田耕作制度存在的问题,提出了在新形势下南方稻田耕作制度调整与改革的对策和思路,对指导目前南方稻田耕作制度的改革具有重要参考价值.  相似文献   
50.
有机农业与常规农业对农田生物多样性影响的比较研究进展   总被引:15,自引:0,他引:15  
一些研究者认为,有机农业不仅在理念上而且在实践上,都有助于促进农田生物多样性的维持和保护.为了促进我国科学界对有机农业与农田生物多样性关联性研究的关注,综述了有机农业对农田生态系统内杂草、地表节肢动物、土壤生物以及鸟类等不同生物类群种类、数量及其多样性的影响.  相似文献   
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