2,657 research outputs found

    The story of phosphorus : sustainability implications of global phosphorus scarcity for food security

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    University of Technology, Sydney. Faculty of Science.The story of phosphorus began with the search for the philosopher’s stone, and centuries later the critical role of phosphorus in soil fertility and crop growth was highlighted. Eventually, phosphorus was implicated in the global environmental challenge of eutrophication. Now, we are on the brink of yet another emerging chapter in the story: global phosphorus scarcity linked to food security. Through a transdisciplinary and systemic inquiry, this thesis has analyzed, reconceptualized and synthesized the physical and institutional dimensions of global phosphorus scarcity in the context of food security, leading to a new framing, ‘phosphorus security’ to guide future work towards a more sustainable and food secure pathway. In a world which will be home to nine billion people by the middle of this century, producing enough food and other vital resources is likely to be a substantial challenge for humanity. Phosphorus, together with nitrogen and potassium, is an essential plant nutrient. It is applied to agricultural soils in fertilizers to maintain high crop yields. Phosphorus has no substitute in food production. Therefore, securing the long-term availability and accessibility of phosphorus is crucial to global food security. However the major source of phosphorus today, phosphate rock, is a non-renewable resource and high quality reserves are becoming increasingly scarce. This thesis estimates peak phosphorus to occur before 2035, after which demand will exceed supply. Phosphorus scarcity is defined by more than just physical scarcity of phosphate rock and this thesis develops five important dimensions. For example, there is a scarcity of management of phosphorus throughout the entire food production and consumption system: the global phosphorus flows analysis found that only 20% of phosphorus in phosphate rock mined for food production actually reaches the food consumed by the global population due to substantial inefficiencies and losses from mine to field to fork. There is also an economic scarcity, where for example, while all the world’s farmers need access to sufficient fertilizers, only those with sufficient purchasing power can access fertilizer markets. Institutional scarcity, such as the lack of governance structures at the international level that explicitly aim to ensure long-term availability of and access to global phosphorus resources for food production that has led to ineffective and fragmented governance of phosphorus, including a lack of: overall coordination, monitoring and feedback, clear roles and responsibilities, long-term planning and equitable distribution. Finally, geopolitical scarcity arising from 90% of the world’s remaining high-grade phosphate rock reserves being controlled by just five countries (a majority of which are subject to geopolitical tensions) can limit the availability of phosphorus on the market and raises serious ethical questions. The long-term future scenarios presented in this thesis indicate that meeting future global food demand will likely require a substantial reduction in the global demand for phosphorus through not only improved efficient use of phosphorus in agriculture, but also through changing diets and increasing efficiency in the food chain. The unavoidable demand for phosphorus could then be met through a high recovery and reuse rate of all sources of phosphorus (crop residues, food waste, manure, excreta) and other sources including some phosphate rock. A ‘hard-landing’ situation could involve further fertilizer price spikes, increased waste and pollution (including eutrophication), increased energy consumption associated with the production and trade of phosphorus fertilizers, reduced farmer access to phosphorus, reduced global crop yields and increased food insecurity. A preferred ‘soft landing’ situation will however require substantial changes to physical and institutional infrastructure, including improved governance structures at the global, national and other levels, such as new policies, partnerships and roles to bring together the food, fertilizer, agriculture, sanitation and waste sectors for a coordinated response. Finally, this thesis proposes a new global goal - phosphorus security - to be integrated in the dominant research discourses and policy debates on global food security and global environmental change. Among other criteria, phosphorus security requires that phosphorus use is decoupled from environmental degradation and that farmers’ access to phosphorus is secured

    Peak phosphorus: Clarifying the key issues of a vigorous debate about long-term phosphorus security

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    This paper reviews the latest information and perspectives on global phosphorus scarcity. Phosphorus is essential for food production and modern agriculture currently sources phosphorus fertilizers from finite phosphate rock. The 2008 food and phosphate fertilizer price spikes triggered increased concerns regarding the depletion timeline of phosphate rock reserves. While estimates range from 30 to 300 years and are shrouded by lack of publicly available data and substantial uncertainty, there is a general consensus that the quality and accessibility of remaining reserves are decreasing and costs will increase. This paper clarifies common sources of misunderstandings about phosphorus scarcity and identifies areas of consensus. It then asks, despite some persistent uncertainty, what would it take to achieve global phosphorus security? What would a 'hard-landing' response look like and how could preferred 'soft-landing' responses be achieved?© 2011 by the authors

    Middle Columbia River Aquatic Nuisance Species Survey

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    Aquatic nonindigenous species (ANS) in the middle Columbia and lower Snake rivers were surveyed during the summer of 2006. The project area included eight reservoirs and the free-flowing, Hanford Reach on the Columbia River. We also conducted a literature review to create a complete list of ANS for the study area

    Less is More? Publicness, Management Strategy, and Organizational Performance in Mental Health Treatment Facilities

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    In this study, the authors seek to identify mechanisms of publicness present within mental health treatment facilities and, subsequently, explore the constraints these mechanisms impose on facilities’ capacities to achieve public outcomes. Through grounded insights from senior managers in this field, political authority, namely through governmental funding and regulation, is identified by 43 of 46 respondents as being an influence on publicness. Authors then uncover the conditions during which publicness, in the form of political authority, constrains organizational achievement of public outcomes. In leveraging managerial perspectives, two distinct constraints emerged: publicness often inhibits organizational efficiency and produces mission drift within these facilities. Findings suggest that managers, under certain conditions (and where legally feasible), may provide greater effectiveness in fulfilling organizational goals and objectives and in achieving public outcomes by maintaining or decreasing an organization’s publicness. Fundamental to effectively managing publicness is understanding the mechanisms germane to both public outcome attainment and failure—the latter of which is explored here

    Landfill Futures: : National Guideline Document

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    This report looks at the past and present roles of landfills in Australian waste management and considers the requirements for a sustainable future. The research used a test case to apply an integrated resource planning model to waste. The results suggest that disposal to landfill may be an expensive and less preferred option compared to others, in many cases, but still have a role to play in specific contexts where the costs of other options are higher

    Space Station Engineering Design Issues

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    Space Station Freedom topics addressed include: general design issues; issues related to utilization and operations; issues related to systems requirements and design; and management issues relevant to design

    The time-dependent expression of keratins 5 and 13 during the reepithelialization of human skin wounds

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    The time-dependent reepithelialization of 55 human surgical skin wounds with a wound age between 8h and more than 2 months was investigated by the immunohistochemical localization of cytokeratins 5 and 13. A complete, rebuilt epidermal layer over the wound area was first detectable in a 5-day-old wound, while all wounds of more than 18 days duration contained a completely reepithelialized wound area. Between 5 and 18 days the basal layer of keratinocytes showed — in contrast to normal skin — only some cells positive for cytokeratin 5. In some, but not all lesions with a wound age of 13 days or more, a basal cell layer completely staining for cytokeratin 5 was demonstrable. This staining pattern was found in all skin wounds with a wound age of more than 23 days. The immunohistochemical detection of cytokeratin 13 which can be observed regularly in non-cornifying squamous epithelia provides no information for the time-estimation of human skin wounds, since no significant temporary expression of this polypeptide seems to occur during the healing of human skin wounds
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