68 resultados para Soil ecology -- Queensland -- Case studies
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This paper studies the exclusion of potential competition as a motivating factor for international mergers. We propose a simple game-theoretic framework in order to discuss the conditions under which mergers that prevent reciprocal domestic competition will occur. Our analysis highlights the shortcomings of antitrust policies based on pre-merger/post-merger concentration comparisons. A review of several recent European cases suggests that actual merger policy often fails to consider potential competition.
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Grassland ecosystems comprise a major portion of the earth’s terrestrial surface, ranging from high-input cultivated monocultures or simple species mixtures to relatively unmanaged but dynamic systems. Plant pathogens are a component of these systems with their impact dependent on many interacting factors, including grassland species population dynamics and community composition, the topics covered in this paper. Plant pathogens are affected by these interactions and also act reciprocally by modifying their nature. We review these features of disease in grasslands and then introduce the 150-year long-term Park Grass Experiment (PGE) at Rothamsted Research in the UK. We then consider in detail two plant-pathogen systems present in the PGE, Tragopogon pratensis-Puccinia hysterium and Holcus lanata-Puccinia coronata. These two systems have very different life history characteristics: the first, a biennial member of the Asteraceae infected by its host-specific, systemic rust; the second, a perennial grass infected by a host-non-specific rust. We illustrate how observational, experimental and modelling studies can contribute to a better understanding of population dynamics, competitive interactions and evolutionary outcomes. With Tragopogon pratensis-Puccinia hysterium, characterised as an “outbreak” species in the PGE, we show that pathogen-induced mortality is unlikely to be involved in host population regulation; and that the presence of even a short-lived seed-bank can affect the qualitative outcomes of the host-pathogen dynamics. With Holcus lanata-Puccinia coronata, we show how nutrient conditions can affect adaptation in terms of host defence mechanisms, and that co-existence of competing species affected by a common generalist pathogen is unlikely.
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Education, especially higher education, is considered vital for maintaining national and individual competitiveness in the global knowledge economy. Following the introduction of its “Free Education Policy” as early as 1947, Sri Lanka is now the best performer in basic education in the South Asian region, with a remarkable record in terms of high literacy rates and the achievement of universal primary education. However, access to tertiary education is a bottleneck, due to an acute shortage of university places. In an attempt to address this problem, the government of Sri Lanka has invested heavily in information and communications technologies (ICTs) for distance education. Although this has resulted in some improvement, the authors of this article identify several barriers which are still impeding successful participation for the majority of Sri Lankans wanting to study at tertiary level. These impediments include the lack of infrastructure/resources, low English language proficiency, weak digital literacy, poor quality of materials and insufficient provision of student support. In the hope that future implementations of ICT-enabled education programmes can avoid repeating the mistakes identified by their research in this Sri Lankan case, the authors conclude their paper with a list of suggested policy options.
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Understanding farmer behaviour is needed for local agricultural systems to produce food sustainably while facing multiple pressures. We synthesize existing literature to identify three fundamental questions that correspond to three distinct areas of knowledge necessary to understand farmer behaviour: 1) decision-making model; 2) cross-scale and cross-level pressures; and 3) temporal dynamics. We use this framework to compare five interdisciplinary case studies of agricultural systems in distinct geographical contexts across the globe. We find that these three areas of knowledge are important to understanding farmer behaviour, and can be used to guide the interdisciplinary design and interpretation of studies in the future. Most importantly, we find that these three areas need to be addressed simultaneously in order to understand farmer behaviour. We also identify three methodological challenges hindering this understanding: the suitability of theoretical frameworks, the trade-offs among methods and the limited timeframe of typical research projects. We propose that a triangulation research strategy that makes use of mixed methods, or collaborations between researchers across mixed disciplines, can be used to successfully address all three areas simultaneously and show how this has been achieved in the case studies. The framework facilitates interdisciplinary research on farmer behaviour by opening up spaces of structured dialogue on assumptions, research questions and methods employed in investigation.
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This report provides case studies of Early Warning Systems (EWSs) and risk assessments encompassing three main hazard types: drought; flood and cyclone. The case studies are taken from ten countries across three continents (focusing on Africa, South Asia and the Caribbean). The case studies have been developed to assist the UK Department for International Development (DFID) to prioritise areas for Early Warning System (EWS) related research under their ‘Science for Humanitarian Emergencies and Resilience’ (SHEAR) programme. The aim of these case studies is to ensure that DFID SHEAR research is informed by the views of Non-Governmental Organisations (NGOs) and communities engaged with Early Warning Systems and risk assessments (including community-based Early Warning Systems). The case studies highlight a number of challenges facing Early Warning Systems (EWSs). These challenges relate to financing; integration; responsibilities; community interpretation; politics; dissemination; accuracy; capacity and focus. The case studies summarise a number of priority areas for EWS related research: • Priority 1: Contextualising and localising early warning information • Priority 2: Climate proofing current EWSs • Priority 3: How best to sustain effective EWSs between hazard events? • Priority 4: Optimising the dissemination of risk and warning information • Priority 5: Governance and financing of EWSs • Priority 6: How to support EWSs under challenging circumstances • Priority 7: Improving EWSs through monitoring and evaluating the impact and effectiveness of those systems
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This paper reports on exploratory work investigating how children with severe and profound learning difficulties register an awareness of small quantities and how they might use this information to inform their understanding. It draws on studies of typically developing children and investigates their application to pupils whose response to conventional mathematical tasks are often limited because they lack relevance and interest. The responses of the three pupils to individualized learning contexts mirror the progression suggested in the literature, namely from awareness of number to simple actions using number cues to problem-solving behaviour
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Requirements for research, practices and policies affecting soil management in relation to global food security are reviewed. Managing soil organic carbon (C) is central because soil organic matter influences numerous soil properties relevant to ecosystem functioning and crop growth. Even small changes in total C content can have disproportionately large impacts on key soil physical properties. Practices to encourage maintenance of soil C are important for ensuring sustainability of all soil functions. Soil is a major store of C within the biosphere – increases or decreases in this large stock can either mitigate or worsen climate change. Deforestation, conversion of grasslands to arable cropping and drainage of wetlands all cause emission of C; policies and international action to minimise these changes are urgently required. Sequestration of C in soil can contribute to climate change mitigation but the real impact of different options is often misunderstood. Some changes in management that are beneficial for soil C, increase emissions of nitrous oxide (a powerful greenhouse gas) thus cancelling the benefit. Research on soil physical processes and their interactions with roots can lead to improved and novel practices to improve crop access to water and nutrients. Increased understanding of root function has implications for selection and breeding of crops to maximise capture of water and nutrients. Roots are also a means of delivering natural plant-produced chemicals into soil with potentially beneficial impacts. These include biocontrol of soil-borne pests and diseases and inhibition of the nitrification process in soil (conversion of ammonium to nitrate) with possible benefits for improved nitrogen use efficiency and decreased nitrous oxide emission. The application of molecular methods to studies of soil organisms, and their interactions with roots, is providing new understanding of soil ecology and the basis for novel practical applications. Policy makers and those concerned with development of management approaches need to keep a watching brief on emerging possibilities from this fast-moving area of science. Nutrient management is a key challenge for global food production: there is an urgent need to increase nutrient availability to crops grown by smallholder farmers in developing countries. Many changes in practices including inter-cropping, inclusion of nitrogen-fixing crops, agroforestry and improved recycling have been clearly demonstrated to be beneficial: facilitating policies and practical strategies are needed to make these widely available, taking account of local economic and social conditions. In the longer term fertilizers will be essential for food security: policies and actions are needed to make these available and affordable to small farmers. In developed regions, and those developing rapidly such as China, strategies and policies to manage more precisely the necessarily large flows of nutrients in ways that minimise environmental damage are essential. A specific issue is to minimise emissions of nitrous oxide whilst ensuring sufficient nitrogen is available for adequate food production. Application of known strategies (through either regulation or education), technological developments, and continued research to improve understanding of basic processes will all play a part. Decreasing soil erosion is essential, both to maintain the soil resource and to minimise downstream damage such as sedimentation of rivers with adverse impacts on fisheries. Practical strategies are well known but often have financial implications for farmers. Examples of systems for paying one group of land users for ecosystem services affecting others exist in several parts of the world and serve as a model.
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Purpose – At the heart of knowledge management (KM) are the people – an organisation's important knowledge asset. Although this is widely acknowledged, businesses seldom understand this axiom in terms of the communities through which individuals develop and share the capacity to create and use knowledge. It is the collective learning that takes place within the social systems, i.e. communities of practice (CoP) that are of particular significance to an organisation from a KM perspective. This paper aims to review, critique, and raise some pertinent questions on the role of CoPs; and with the help of case studies shed light on the “goings-on” in construction practices. Design/methodology/approach – After critically reviewing the literature on CoPs and querying some underlying assertions, this research investigates how these issues are addressed in practice. A case study approach is adopted. Three organisations operating in the construction sector are interviewed for the purpose of this paper. Findings – Case study findings highlight the potential challenges and benefits of CoPs to a construction organisation, the role they play in generating and delivering value to the organisation and their contribution towards the collective organisational intelligence. From the findings, it is clear that the question is not whether communities exist within organisations, but how they deliver value to the organisation. From an organisational perspective, the key challenge is to provide an environment that is conducive to developing and nurturing such communities as opposed to merely creating them. Practical implications – Challenges and benefits demonstrated through the case studies should be taken in context. The findings are not intended to be prescriptive in nature, but are intentionally descriptive to provide contextual data that allow readers to draw their own inferences in the context of their organisations. They should be applied taking into account an organisation's unique characteristics and differentiators, the dynamics of the environment in which it operates and the culture it harbours within. Originality/value – Investigating the role of CoPs in the context of case study construction organisations forms the prime focus of this paper.
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A series of government initiatives has raised both the profile of ICT in the curriculum and the expectation that high quality teaching and learning resources will be accessible across electronic networks. In order for e-learning resources such as websites to have the maximum educational impact, teachers need to be involved in their design and development. Use-case analysis provides a means of defining user requirements and other constraints in such a way that software developers can produce e-learning resources which reflect teachers' professional knowledge and support their classroom practice. It has some features in common with the participatory action research used to develop other aspects of classroom practice. Two case-studies are presented: one involves the development of an on-line resource centred on transcripts of original historical documents; the other describes how 'Learning how to Learn', a major, distributed research project funded under the ESRC Teaching and Learning Research Programme is using use-case analysis to develop web resources and services.
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The aim of the article is to present and discuss a study in which Finnish, English and Swedish teachers and student teachers described the implications of being a teacher. It is cross-national and consists of multiple case studies. Data were collected through twenty-four focus group dialogues, and 110 teachers/student teachers participated in the study. According to the study, we have found that teachers and student teachers in all three countries promoted pupils’ development of critical thinking, which is another way of saying that they focused on ‘the attitudes and values’ aspect of citizenship education; however, this was most evident in the Finnish and the Swedish focus groups. In England there is a subject emphasis to the professional role, the three countries ranked the topics (the pupils; the subject; the organization; the society; teacher identity; parents) equally, in Finland the teacher role did not appear to be as post modern as in the two other countries.
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Global temperatures are expected to rise by between 1.1 and 6.4oC this century, depending, to a large extent, on the amount of carbon we emit to the atmosphere from now onwards. This warming is expected to have very negative effects on many peoples and ecosystems and, therefore, minimising our carbon emissions is a priority. Buildings are estimated to be responsible for around 50% of carbon emissions in the UK. Potential reductions involve both operational emissions, produced during use, and embodied emissions, produced during manufacture of materials and components, and during construction, refurbishments and demolition. To date the major effort has focused on reducing the, apparently, larger operational element, which is more readily quantifiable and reduction measures are relatively straightforward to identify and implement. Various studies have compared the magnitude of embodied and operational emissions, but have shown considerable variation in the relative values. This illustrates the difficulties in quantifying embodied, as it requires a detailed knowledge of the processes involved in the different life cycle phases, and requires the use of consistent system boundaries. However, other studies have established the interaction between operational and embodied, which demonstrates the importance of considering both elements together in order to maximise potential reductions. This is borne out in statements from both the Intergovernmental Panel on Climate Change and The Low Carbon Construction Innovation and Growth Team of the UK Government. In terms of meeting the 2020 and 2050 timeframes for carbon reductions it appears to be equally, if not more, important to consider early embodied carbon reductions, rather than just future operational reductions. Future decarbonisation of energy supply and more efficient lighting and M&E equipment installed in future refits is likely to significantly reduce operational emissions, lending further weight to this argument. A method of discounting to evaluate the present value of future carbon emissions would allow more realistic comparisons to be made on the relative importance of the embodied and operational elements. This paper describes the results of case studies on carbon emissions over the whole lifecycle of three buildings in the UK, compares four available software packages for determining embodied carbon and suggests a method of carbon discounting to obtain present values for future emissions. These form the initial stages of a research project aimed at producing information on embodied carbon for different types of building, components and forms of construction, in a simplified form, which can be readily used by building designers in optimising building design in terms of minimising overall carbon emissions. Keywords: Embodied carbon; carbon emission; building; operational carbon.
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Considered as one of the most available radionuclide in soileplant system, 36Cl is of potential concern for long-term management of radioactive wastes, due to its high mobility and its long half-life. To evaluate the risk of dispersion and accumulation of 36Cl in the biosphere as a consequence of a potential contamination, there is a need for an appropriate understanding of the chlorine cycling dynamics in the ecosystems. To date, a small number of studies have investigated the chlorine transfer in the ecosystem including the transformation of chloride to organic chlorine but, to our knowledge, none have modelled this cycle. In this study, a model involving inorganic as well as organic pools in soils has been developed and parameterised to describe the biogeochemical fate of chlorine in a pine forest. The model has been evaluated for stable chlorine by performing a range of sensitivity analyses and by comparing the simulated to the observed values. Finally a range of contamination scenarios, which differ in terms of external supply, exposure time and source, has been simulated to estimate the possible accumulation of 36Cl within the different compartments of the coniferous stand. The sensitivity study supports the relevancy of the model and its compartments, and has highlighted the chlorine transfers affecting the most the residence time of chlorine in the stand. Compared to observations, the model simulates realistic values for the chlorine content within the different forest compartments. For both atmospheric and underground contamination scenarios most of the chlorine can be found in its organic form in the soil. However, in case of an underground source, about two times less chlorine accumulates in the system and proportionally more chlorine leaves the system through drainage than through volatilisation.
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This is a comprehensive textbook for students of Television Studies, now updated for its third edition. The book provides students with a framework for understanding the key concepts and main approaches to Television Studies, including audience research, television history and broadcasting policy, and the analytical study of individual programmes. The book includes a glossary of key terms used in the television industry and in the academic study of television, there are suggestions for further reading at the end of each chapter, and chapters include suggested activities for use in class or as assignments. The case studies in the book include analysis of advertisements, approaches to news reporting, television scheduling, and challenges to television in new contexts of viewing on computers and mobile devices. The topics of individual chapters are: studying television, television histories, television cultures, television texts and narratives, television genres and formats, television production, television quality and value, television realities and representation, television censorship and regulation, television audiences, and the likely future for television.
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Europe has the greatest concentration of botanic gardens in the world, they cultivate extensive collections of plants that include samples of European threatened plant species. This study looks at the effectiveness of these collections in supporting species conservation. A three part study is presented: (1) the results of a survey and assessment of threatened plants in botanic gardens, as defined by the Bern Convention; (2) case studies illustrating current issues in the ex situ management of European threatened plant species; and (3) presentation of policy recommendations on further improving botanic garden contributions to European plant conservation. The survey indicated that of 119 European botanic gardens in 29 European countries, 105 are cultivating 308 of the 573 threatened plant species listed by the Bern Convention. The survey identified 25 botanic gardens in 14 countries undertaking 51 conservation projects focused on 27 Bern listed species. In particular this survey has established that the majority of taxa are held in a small number of collections, dominated by non-wild origin accessions, and are not adequately documented. The majority of specimens in botanic gardens are cultivated out of the range country and not contributing to a specific conservation project. We review the genetic representation and documentation of origin in collections. Existing plant collections contain representatives of populations, now lost in the wild and maintain samples of at least nine European plant taxa identified as 'Extinct in the Wild'. However, inadequate standards of record keeping has compromised the conservation value of many collections. We highlight the dangers of hybridisation and disease in ex situ collections. The results suggest that botanic garden collections are skewed towards horticulturally robust and ornamental species and do not fully reflect priorities as defined by the Bern Convention. Recognising the limitations of traditional botanic garden collections we propose that botanic gardens more effectively utilise their two core competencies, namely scientific horticulture and public display and interpretation. The unique horticultural skills resident in European botanic gardens could be more effectively utilised through the application of horticulture to the management of wild populations.