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1.
东太平洋柱状沉积物的古气候和古环境记录   总被引:1,自引:2,他引:1  
太平洋深海盆地的远洋沉积物在物质组成和来源上远较大陆边缘简单.由于远离大陆,又有海沟与周边大陆分隔,太平洋深海沉积物中通常不包含由河流水系搬运而来的悬浮物,因此从深海沉积物中提取古气候、古环境信息可以避免诸多地质因素相互叠加和干扰[1].深海远洋沉积物中的主要组分是风成陆源碎屑(包括火山碎屑)和来自上层海水的生源组分(降落到洋底的生物壳体)以及由海解作用形成的自生矿物[2],其中陆源碎屑的相对含量、粒度及矿物成分可以反映大气环流的强度及物源区的气候环境[1],生源组分的组成、相对含量和丰度以及种属含量变化则与表层海水的生产力和溶解作用有关.  相似文献   
2.
Alex Hughes   《Geoforum》2006,37(6):1008-1020
This paper explores what happens when corporations engage explicitly in practices of organisational learning not only to become better capitalists by generating ever more innovative ways of maintaining profitability, improving competitiveness and maximising shareholder value, but also to become more responsible corporate citizens in their business practices. In particular, I evaluate the ways in which UK food and clothing retailers are learning to develop their ethical trading programmes in response to political calls for more responsible trading. Thrift’s [Thrift, N., 2005. Knowing Capitalism. Sage, London] notion of ‘knowledgeable, or soft, capitalism’ is adopted to understand the creative and experimental ways in which retailers and their mentors (ethical consultancies, social auditors and multi-stakeholder organisations) are learning to trade ethically. Two specific examples of formal learning spaces experienced by UK food and clothing retailers are examined: (i) training courses on social auditing and (ii) corporate awareness-raising courses on ethical trade. These courses are shown to encompass various participative and affective practices of learning. And while particular limits to the success of these courses are argued to exist, ethical learning practices discussed in this paper are nonetheless suggested to play a role in the making of new, albeit moderate, forms of responsible capitalism.  相似文献   
3.
The article analyzes patterns in the distribution of manufacturing job losses that have been certified as trade‐induced by the U.S. Department of Labor. Spatial patterns in the likelihood of job loss are examined in the United States for the period from 1994 to 2002, with particular emphasis on county‐level patterns in New England. The findings demonstrate that the pattern of losses was correlated with measures of economic vitality and competitiveness including per capita income, educational attainment, occupational structure, and inventiveness. These results suggest that trade‐induced deindustrialization is borne most heavily by places ill‐equipped to compete in a more open, integrated international economy.  相似文献   
4.
Alpine medicinal plant trade and Himalayan mountain livelihood strategies   总被引:5,自引:0,他引:5  
Commercial alpine medicinal plants are collected from the wild by local rural households throughout the Himalaya and sold in order to increase household incomes. Recent studies indicate that this annual trade amounts to thousands of tonnes of roots, rhizomes, tubers, leaves, etc., worth millions of US dollars. The main market is in India. Based on a national survey, including the most commonly traded species, and a village study this paper investigates the importance of the alpine medicinal plant trade at national and local levels in Nepal. The national survey included standardized open-ended interviews with 232 harvesters, 64 local traders, 66 central wholesalers, 47 regional wholesalers, and 16 production companies. The village survey is based on the daily records of household activities in 15 households in a one-year period. The annual Nepalese alpine and sub-alpine medicinal plant trade is conservatively estimated to vary from 480 to 2500 t with a total harvester value of US$0.8–3.3 million; the average harvester value is estimated at US$66.0 ± 99.0. The trade in 1997/98 amounted to 1600 t with a harvester value of US$2.3 million and an export value equivalent to 2.5% of total export from Nepal. Medicinal plant harvesting was found to constitute an integrated part of local livelihood strategies, contributing from 3 to 44% (average of 12%) of the annual household income. Importance at household level depended on land and animal holdings, and the availability of adult male labour. The validity and reliability of methods and analyses is evaluated, and issues of conservation and management of alpine medicinal plant species under the community forestry scheme are discussed.  相似文献   
5.
文章总结了以往国内学者对城市功能区域的数量化方法研究,认为在层次分析法等方法中对指标权重的确定存在主观因素过多等不足,严重影响了研究的科学性和准确性,文章为了克服上述不足,将多属性效用理论的代理价值法与博弈论的方法应用于城市功能区的布局与研究,并以深圳市南山区物流中心的选址为例,阐述了代理价值法与博弈论在城市功能区域中的具体实践操作。  相似文献   
6.
Becky Mansfield 《Geoforum》2003,34(3):329-342
This paper addresses the cultural economy of nature and the material culture of economic practice. Attending to ways that cultural notions about the biophysical world play key roles in political economic conflicts, discussion centers on two recent debates involving the cultural economy of seafood production and trade. The first debate is over whether the label “catfish” should include catfish imported from Vietnam into the United States; the second deals with whether fish and shellfish should be eligible to be certified “organic” under new US regulations. Analysis reveals that the key dynamic in these debates is not necessarily how people think about “nature”, but instead is how people make distinctions about the world. Rather than focusing on what is natural or not, key actors make distinctions among both organisms and environments. The ways that different groups define and enclose the biophysical world works to distinguish places as either appropriate or not for certain kinds of production activities. The overall argument is that significance and meaning of the biophysical become implicated in economic geographies by making distinctions about the world that then become important for how economic activity can work. As such, cultural economic approaches should attend to the ways that the biophysical is involved in relations such as competition and international trade, while nature-society approaches should shift focus from Nature to specific aspects of the biophysical world.  相似文献   
7.
陈斐 《干旱区地理》1997,20(4):54-60
本文在分析新疆对中亚五国的外贸结构基础上,阐述了目前在与中亚五国的贸易中存在的一些问题,提出相应的对策建议,以推动新疆与中亚五国外贸发展的良性循环。  相似文献   
8.
90年代世界贸易发展及空间格局变化的新特点   总被引:3,自引:0,他引:3  
在世界贸易组织、日趋强烈的开放的区域主义倾向、跨国公司强劲的直接投资影响下,世界贸易正在经历着巨大变化,处在一个新的转换时期。本文从影响当今世界贸易发展的多重因素分析,揭示90年代世界贸易增长、内容结构以及空间格局发展变化的新特征,并展望世界贸易的未来发展。  相似文献   
9.
South Africa’s cities have experienced dramatic changes over the past decade. Cities are now home to a multiracial population, and have been transformed by new forms of economic and social interaction. For some, these changes have become a significant source of fear and anxiety. In this paper, we examine reactions to urban spatial change in the city of Durban, as expressed in local newspapers and interviews with suburban residents. We describe how the discourses of urban change in Durban have centred on the increased presence of street traders within the city’s public spaces, and the various ways in which the activity of street trade has disrupted long-established modernist norms governing the occupation and use of the urban space. Specifically, we offer a detailed reading of three prominent narratives within the discussion of street traders in Durban--chaos, congestion and pollution. We argue that street traders have come to embody a wide range of more deeply seated cultural anxieties, which have been brought to the fore in the context of South Africa’s transition. These anxieties arise from the ways in which modern understandings of order, agency and subjectivity have been called into question by material changes in the city, and have implications for the nature of citizenship and civic engagement in post-apartheid South Africa.  相似文献   
10.
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