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121.
This paper examines the differing modes of insertion of the Australian and New Zealand apple industries into world apple markets, part of the evolving global fresh fruit complex. It is argued that the mix and behaviours of key actors in the global apple industry are realigning market links and production systems. Industry actors in Australia and New Zealand are confronting issues of quality and sustainability as a result of pressures from consumers, regulatory measures in traditional and emerging markets, and new technologies of production and distribution. Governments are laying the foundations of national, regional and industry sustainability policies. An examination of the detailed structure and adjustments of the apple industry in Hawkes Bay and Tasmania reveals considerable differences in local responses, institutions and degree of restructuring of markets. The preferences and quality control requirements of export markets are increasingly important, to the extent that cultural dimensions appear to be altering the commodification process.  相似文献   
122.
This paper develops a decision support system for evaluation of wetland ecosystem management strategy and examines its, so far partial, application in a case study of an important complex coastal wetland known as the Norfolk and Suffolk Broads, in the east of England, UK. Most managed ecosystems are complex and often poorly understood hierarchically organized systems. Capturing the range of relevant impacts on natural and human systems under different management options will be a formidable challenge. Biodiversity has a hierarchical structure which ranges from the ecosystem and landscape level, through the community level and down to the population and genetic level. There is a need to develop methodologies for the practicable detection of ecosystem change, as well as the evaluation of different ecological functions. What is also required is a set of indicators (environmental, social and economic) which facilitate the detection of change in ecosystems suffering stress and shock and highlight possible drivers of the change process. A hierarchical classification of ecological indicators of sustainability would need to take into account existing interactions between different organization levels, from species to ecosystems. Effects of environmental stress are expressed in different ways at different levels of biological organization and effects at one level can be expected to impact other levels, often in unpredictable ways. The management strategy, evaluation methodologies and indicators adopted should also assess on sustainability grounds whether any given management option is supporting, or reducing, the diversity of functions which are providing stakeholders with the welfare benefits they require.  相似文献   
123.
Tunisia is a marginal country hydrologically and it has adopted a number of distinctive methods of water management for agriculture. The central region supports modern dam irrigation, whilst traditional rainwater harvesting is practiced in the south. These contrasting techniques are described and evaluated in terms of sustainability using empirical field data and secondary literature for two study sites. Research focuses primarily on the physical environment, but socio-cultural and economic viability are also examined. Analysis indicates that traditional water management advantageously partitions the continuum dividing hazards and resources through subtle manipulation of the environment. A potentially hazardous environment is rendered secure by resourceful water management based on community action and cumulative knowledge. This practice minimizes community dependency and local economic imbalance. With dam irrigation, carrying capacity is established more forcibly by centralized control in order to place society within world markets. An almost total break from environmental variability is made in the short term, but this can lead to disequilibrium over longer durations. Additionally, the spatial and social distributions of development are uneven. In Tunisia, maintenance of traditional methods can reduce the negative impacts caused by modern programmes and support their positive characteristics. A mix of both methods offers a foundation to sustainable water supply in the new millennium.  相似文献   
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125.
黄河流域环境对水资源开发承受力的思考   总被引:8,自引:0,他引:8  
尹国康 《地理学报》2002,57(2):224-231
根据黄河1919-1999年系列水沙资料,系统分析了其下游水沙变化时空过程,揭示了其发生断流原因及由此引发的环境问题,模拟了不同历史时期水情条件下环境用水需求量,并对如何提高黄河水资源开发承受能力,如何满足其环境用水提出看法。  相似文献   
126.
可持续性转型地理研究综述与展望   总被引:3,自引:0,他引:3  
可持续性转型是近20 a欧洲学界的新兴研究领域,它关注既有社会技术系统向更加可持续的生产与消费模式的根本性转变,对不少国家和地区的绿色转型政策实践已经产生了重要的影响。近年来,越来越多学者开始关注可持续性转型与经济地理的交叉融合,可持续性转型地理逐渐发展成为一个新兴的研究议题,着重从空间根植性与多尺度交互2个维度回答“可持续性转型在哪里发生”的问题。论文在简要总结可持续转型理论与分析框架的基础上,系统回顾和评述了转型地理研究进展与不足,并着重从中国的情境提出未来该议题的几个重点方向:① 基于中国语境下的的转型地理概念化和理论框架构建;② 后发地区可持续性转型与绿色产业追赶;③ 城市可持续性转型差异与联系;④ 多尺度交互下转型主体能动性与权力博弈;⑤ 人工智能等新兴技术对可持续转型的影响。  相似文献   
127.
Based on the basic selection criteria of Globally Important Agricultural Heritage Systems (GIAHS) and food and livelihood security research trends, this paper established an evaluation framework and indicator system for food and livelihood security in GIAHS and selected the first GIAHS site in the Qinghai-Tibet Plateau as a case for empirical evaluation. The results demonstrate that the food and livelihood security of farmers at this site was at a medium level, with an average evaluation value of 2.91, which still lagged behind the level of better food and livelihood security. Specifically, the average values of farmers’ evaluation of food security and livelihood security were 1.43 and 1.48, respectively, which show that farmers’ food security in the study area was at a medium level and that of livelihood security was relatively good. Simultaneously, the more simple a farmers’ economic activities (i.e., agriculture-oriented economic activities or non-agriculture-oriented economic activities), the worse their food and livelihood security; while the more diversified the economic activities (i.e., engaged in part-time economic activities), the better the food and livelihood security.  相似文献   
128.
Conservation-compatible development of rural communities is an important part of nature conservation objectives. Understanding the role of agriculture, which is often practiced in or bordering the protected areas in rural China, is critical for managing conservation networks considering that limited spatial areas are available for enclosed protected areas. Important Agricultural Heritage Systems stand out for their multi-functionality, and some of their values are compatible with nature conservation. This paper examined the concept, management objectives and resource management characteristics of the Important Agricultural Heritage Systems (IAHS) by analysing their interactions with national parks in terms of community development. The results reveal that management strategies of dynamic conservation, integrated protection and adaptive management of the IAHS can contribute to those national park management objectives concerning conservation-compatible livelihood. However, the typology of the protected area system, including the traditional agricultural system as a new type, needs further consideration.  相似文献   
129.
Large-scale, sustainable urban development projects can transform surrounding neighborhoods. Without precautionary policies, environmental amenities produced by these projects, such as parks, trails, walkability, and higher-density development, tend to result in higher land and housing costs. This will make it harder for a low- and moderate-income households to live near the projects, and neighborhoods are likely to become increasingly affluent. The Atlanta Beltline will ultimately connect 45 Atlanta neighborhoods via a 22-mile loop of trails, parks, and eventually a streetcar, all of which follow abandoned railroad tracks. This paper examines the effect of the Beltline on housing values within one half mile. From 2011 to 2015, depending on the segment of the Beltline, values rose between 17.9 percent and 26.6 percent more for homes within a half-mile of the Beltline than elsewhere. The implications for housing affordability and neighborhood change of projects like the Beltline, and associated policy questions, are addressed.  相似文献   
130.
ABSTRACT

Air travel has become central to Australian academic practice, with flying increasingly seen as crucial to the progression of successful academic careers. This paper seeks to understand why academic air travel has come to be perceived as so necessary, particularly given its significant environmental, social, and economic implications. Drawing on the mobilities paradigm and social practice theory, we seek to understand how air travel practices are a key part of contemporary academic careers. We conducted an online survey of 301 academics and 24 in depth semi-structured interviews to understand academic air travel in Australia, finding that it is seen as a means to connect and collaborate within and between academic communities, and to counteract the effects of ‘remoteness'. This remoteness is experienced domestically and internationally, by Australian academics who feel they must travel to perceived centres of knowledge production to further their careers. Academics often frame their ‘need' for connections as necessarily involving physical co-presence. Air travel offers career benefits for those who can take advantage of it, and corresponding drawbacks for those ‘stuck on the ground’. We conclude by discussing the need for valuing localised forms of collaboration as markers of success, and developing imaginative alternatives to academic flying.  相似文献   
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