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In New Zealand environmental management is essentially the responsibility of land managers. Management decisions affect both production/productivity and the environment. However, responsibility for ensuring positive environmental outcomes falls on both local (Regional) and Central Government, and both they and international agencies such as the OECD would wish to monitor and report on changes. In terms of policy, strong links have been established via Central and Regional Government to land managers. Consumers in the market place are also, increasingly, requiring responsibility for positive environmental outcomes of those who purchase and process primary products. Strong links for responsibility have been established between our international markets and processing businesses and there is a noticeable strengthening of the links from the processors to the land manager/producer. In New Zealand a range of initiatives has been developed and implemented over recent times, whereby land managers are taking increasing responsibility for accounting for the environmental outcomes of their production activities. The range covers the spectrum from voluntary to compulsory (e.g., in order to meet market requirements) and from those initiated by customers to processor and/or producer initiatives. This paper follows the evolution of the principles that drove the predominant activities of the period and the processes that initiated the changes in environmental management. As the focus of agriculturalists changed from pioneering in a new world, to establishing a production base, to economic reality, and finally to environmental responsibility, the processes of extension adapted to meet the new challenge.  相似文献   
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Summary The nature and evidence of the gaia and geochemical hypotheses describing the dynamics of the ecosphere are reviewed. In particular, the ways in which the unorthodox gaia hypothesis challenges the orthodox global models of geochemistry are discussed in the context of the logic and sociology of science. It is argued that the gaia hypothesis offers environmental scientists a working hypothesis of unusual promise, especially for understanding the processes underlying the long-term dynamics of the global environmental system.Dr Ian Moffatt is a member of the staff of the Department of Environmental Science at the University of Stirling.  相似文献   
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A review is presented on trace gas exchange of CH4, CO, N2O, and NOx arising from agriculture and natural sources in the world's semiarid and arid zones due to soil processes. These gases are important contributors to the radiative forcing and the chemistry of the atmosphere. Quantitative information is summarized from the available studies. Between 5 and 40% of the global soil-atmosphere exchange for these gases (CH4, CO, N2O, and NOx) may occur in semiarid and arid zones, but for each of these gases there are fewer than a dozen studies to support the individual estimates, and these are from a limited number of locations. Significant differences in the biophysical and chemical processes controlling these trace gas exchanges are identified through the comparison of semiarid and arid zones with the moist temperate or wet/dry savanna land regions. Therefore, there is a poorly quantified understanding of the contribution of these regions to the global trace gas cycles and atmospheric chemistry. More importantly, there is a poor understanding of the feedback between these exchanges, global change, and regional land use and air pollution issues. A set of research issues is presented.  相似文献   
55.
Two paradigms of professional development in environmental education   总被引:3,自引:0,他引:3  
Summary In environmental education in this information age, it is particularly important to adopt the approach of enquiring critically into the environmental, educational and social values informing environmental, educational and social actions when and where required, rather than to simply adopt the approach of emphasising the acquisition and retention of information of an alleged universal type — information drawn from the stockpile of objective knowledge collected by others. This paper argues that to achieve this aim, environmental education in an information age requires aparadigm shift in the areas of professional development — a shift from a paradigm of information technology to a paradigm of information critique. A perspective on the form of this paradigm shift in the particular field of professional development in environmental education is the subject of this paper.Dr Ian Robottom is Senior Lecturer in the Curriculum Studies Centre of the School of Education, at Deakin University, Australia. His main interests lie in teacher education, educational enquiry, and environmental education. He conducts an off-campus environmental education course (B.Ed level) for practising teachers studying at a distance, is a member of the Council of the Australian Association for Environmental Education., and Editor of theAustralian Journal of Environmental Education.  相似文献   
56.
The EEC Shellfish Directive is a policy designed to protect and, where necessary, improve the quality of designated shellfish waters. Its implementation within the UK, however, has had no effect upon water quality for two reasons. First, the policy has important defects, having ambiguities concerning public health provisions and lacking designation criteria. Second, UK government has sought to achieve formal compliance, while at the same time ensuring that its full financial impact on public expenditure has been contained. Consequently, only those fisheries which already comply with water quality standards have been designated. Within Wales, one fishery has been designated, while other, commercially more important, but grossly contaminated shellfisheries have not.  相似文献   
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Applications of in situ agrobiodiversity conservation practices within agricultural production systems have the potential to reduce the risks of agricultural modernisation and enhance sustainable development. The aims and approaches for in situ conservation differ according to the requirements of communities and nations. Approaches to in situ conservation in the decade after the Convention of Biological Diversity are reviewed within the contexts of marginal agricultural systems in Nepal, Turkey and Switzerland. Numerous approaches are currently utilised, including: the informal de facto retention of agrobiodiversity; the provision of state assistance; the marketing of agrobiodiversity products; the use of technological innovations to develop local diversity; the establishment of conservation reserves; community assistance programmes and the raising of awareness of the issue amongst all sectors of societies. Emerging complementary in situ approaches applicable in the rural margins suggest a framework for effectively conserving agrobiodiversity by working with local people.  相似文献   
59.
We are exploiting materials and concepts from food science to create functionalized, environmentally friendly derivatives of the biopolymer chitosan, a byproduct of seafood processing. Functional groups are grafted onto chitosan using tyrosinase, the enzyme responsible for food browning. The functionalizing groups studied include low-molecular-weight phenols derived from natural sources and high-molecular-weight proteins. The approach of using low-molecular-weight phenols to functionalize chitosan is illustrated with arbutin, a natural phenol found in pears. Results demonstrate that tyrosinase initiates reactions that lead to the conversion of arbutin–chitosan solutions into gels. These gels can be rapidly broken by treatment with the chitosan-hydrolyzing enzyme chitosanase, demonstrating that the chitosan derivatives remain biodegradable. We briefly review other studies in which low-molecular-weight natural phenols are enzymatically grafted onto chitosan to confer functional properties. The creation of co-polymers is illustrated by results in which tyrosinase is used to couple gelatin onto chitosan. Gelatin is a proteinaceous byproduct of meat production. The tyrosinase-generated gelatin–chitosan conjugates have been observed to offer interesting rheological and thermal properties. These results demonstrate the potential for using renewable resources and enzymatic processing to create environmentally friendly polymers with useful functional properties.  相似文献   
60.
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