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1.
This paper analyses the spatial and temporal effects of a freshwater discharge (Canal Andreoni) on the macroinfauna community and its habitat in a sandy beach of Uruguay. Bimonthly, we examined 17 environmental variables plus macroinfauna abundance, biomass, richness, evenness and diversity of three sites: Andreoni, at the canal mouth, Coronilla, at 1 km, and Barra, at 13 km from the mouth. Both univariate and multivariate techniques showed an increasing degree of perturbation towards the canal. This was reflected by abiotic and biotic differences between sites and by a consistent two-dimensional ordination of the samples. A clear seasonal pattern was found, specially accentuated at Coronilla, where the effects of the canal were stronger in winter and weaker in summer. Multivariate linking between macroinfauna and its habitat highlighted the role of salinity as explanatory variable of the observed trends.  相似文献   
2.
地方认同是衡量人地情感、理解人与地方认知关系的重要概念,能够反映人地互动的复杂动态关系。企业社区作为重要的城市居住空间,理解居民地方认同对于科学开展城市社区更新、街区振兴与可持续发展具有重要意义。以西安市西北第一印染厂社区为例,采用扎根理论方法,分析社会环境变迁和社区重构影响下,居民个人身份与地方认同的变化及作用机理。研究发现:1)企业社区居民个人身份认同是从单位人向社会人,以及未来作为留守老年群体的转变。2)延续传承的集体记忆维系居民积极式认同,社会交往生疏化和社区管理社会化加剧地方认同弱化,破败的建筑环境和落后的配套设施带来消极式认同。3)居民在生活、成长的企业社区环境和社会互动中构建了自身及对地方的认同,随着外部社会环境与内部居民个体特征而变化。外部社会环境的国企改革、住房改革使企业转轨、社区社会空间转变,加以居住时间差异、个体特征、心理因素与个人经历变化等内部因素,共同塑造居民的地方认同及其变化过程。  相似文献   
3.
Communities of practice play an important role in innovation processes. It is, however, still unclear what their particular function is. In this article the authors seek first to develop further systematic differentiations between different types of knowing in practice to provide the conceptual ground for studying the influences of knowing in practice on innovation in a comparative way. Therefore, existing inductive approaches are complemented with deductive elements that highlight different impulses of reflexivity (push vs. pull) and different internal logics of reflexivity (rationalist vs. aesthetic). Second, in this article the authors introduce a dynamic approach which focuses on core ideas of innovation processes from a spatial perspective. In such a dynamic view types of knowing in practice have an impact as sources and resources of innovation. As sources of innovation they form a particular locus in which novel ideas emerge and subsequently take particular trajectories. As resources of innovation they intervene at subsequent stages of the process and propel further the translation process of a novel idea becoming eventually a valuable and practicable solution.  相似文献   
4.
为探索强烈地震的前兆,在欧洲共同体的支持下,中国和英国的地震学家共同在北京西北的延庆—怀来盆地建立了一个数字地震台网.延庆—怀来数字地震台网由5个野外台和一个中心台构成。研究工作的重点是探索强烈地震前地震横波分裂现象中的参数变化.1995年4月30日台网建成并投入运作.1995年7月下旬.怀来地区发生ML=4.0地震及其余震,延庆—怀来数字地震台网很好地记录了这一地震序列。初步的分析表明.这一地震序列表明了怀来县城以南6—8km处,怀来盆地南缘下部的断层活动,它与怀来地区地表有明显出露的主要断裂没有明显的直接联系。  相似文献   
5.
Official figures submitted in 2002 showing the trends of GH gases during the period 1990-2000 indicate that Spain is a long way from in attaining its commitments with the international and national programmes on climate change. Both structural and cultural factors are used to explain the evolution in climate politics and the growth of its emissions with particular emphasis given to the lack of public participation in this respect. It is also argued that Spain will have either to buy emission reductions abroad or/and find new ways to reduce GH in a more decentralised manner in tune with its current Autonomous Communities’ (ACs) political organisation.  相似文献   
6.
Fuelwood is the main source of the energy in mountainous regions.Hence,annual wood consumption is very high.Information on fuelwood resources,and their extraction and availability is very scanty.Therefore,present study was carried out to study the diversity of fuelwood species,annual collection,preference and availability of fuel species in the forests.Thirty four species(25 trees and 9 shrubs) were extracted for fuel by the inhabitants.Total collection and species preference was highest for Picea smithiana,Cedrus deodara,Indigofera heterantha,Pinus wallchiana and Sorbaria tomentosa,respectively.Resource use index indicating use pressure was highest for P.smithiana,C.deodara,I.heterantha and Abies pindrow,respectively.Besides native species,some non-native horticultural and agroforestry species such as Malus pumila,P.domestica,Celtis australis,etc.were also being used as fuel.Preferred species showed their availability in eight forest types whereas,population and regeneration status was poor.Therefore,immediate actions are suggested to sustain current and future demand of fuelwood.The afforestation of degraded,uncultivated and marginal lands through high quality and preferred fuel species might reduce pressure on wild and selective species.  相似文献   
7.
Rural Tourism: A case of lifestyle-led opportunities   总被引:1,自引:0,他引:1  
Tourism is often seen as a panacea for the ills of declining rural communities. The paper argues that there is an element of blind optimism in this view although a shift of focus from production to consumption within advanced economies like Australia's will undoubtedly provide opportunities for the development of the leisure, recreation and tourism industries, both in metropolitan and rural areas. The paper suggests that an increased focus on lifestyle will come to characterise Australia. Some rural communities will be able to capitalise on this, both for temporary visitors and for in-migration, but many will not. The well-established concepts of threshold and range, when coupled with the idea of specialisation, will have a large influence on which places 'win' and which 'lose' in any lifestyle-led and leisure-oriented society. 'Place marketing' will become increasingly important for towns competing against each other for the 'leisure and lifestyle dollar'.  相似文献   
8.
The South African squid fishery is based on a single species, Loligo reynaudi, locally referred to as chokka and commonly found around the Agulhas Bank and West Coast shelf of South Africa. The existing long term rights for participation in the fishery expire at the end of 2013 and a new set of rights will have to be issued. Progress made to date in achieving the objectives of the South African Marine Living Resources Act of 1998 (MLRA), including progress towards greater equity, will be an important consideration in allocation decisions. The draft Small-Scale Fisheries Policy, scheduled to be adopted in 2013, could also influence the criteria to be used. This study updates the information on the current structure and functioning of the squid jig sector and considers the likely performance of two alternative access allocation scenarios against the current and evolving policy goals. The study reaffirms that the squid fishery is an important contributor to human well-being in South Africa and particularly in the Eastern Cape Province but there is scope for improvement in the extent of transformation and equity. The study concludes that, as a result of a common lack of experience and capital amongst potential new entrants, the risks associated with transformation in this fishery are likely to be high, especially if the option of allocating rights to community-based legal entities was to be used. The risks could be reduced by ensuring that a number of pre-conditions were met. These include, amongst others, not allowing total effort in the fishery to increase; ensuring effective management by the responsible government authorities; adequate capacity building of new entrants, whether individuals or cooperatives; and ensuring new entrants have viable business plans.  相似文献   
9.
Increases in wildfire frequency and extent in rangelands pose a growing threat to private property and ecosystem health. The state of Idaho, USA, recently promoted rangeland fire protection associations (RFPAs)—nonprofit organizations of local citizens who contribute to firefighting efforts on public rangelands—as one way to mitigate rangeland wildfire risk. This study used in-depth interviews with RFPA members and land management professionals to explore the local circumstances that influenced the establishment and functioning of one RFPA. Results indicate that intergenerational ties to “working the land,” existing reciprocity among neighbors, a culture of self-reliance, and informal social networks all contributed to RFPA formation and functioning. Interaction between RFPA members and professionals improved their relationships and promoted shared understandings about wildfire response. We conclude by discussing conditions that might enable or inhibit RFPAs in other areas and how our findings advance research on adapting mitigation programs to local context.  相似文献   
10.
Fisheries management in the United States, the European Union, and other parts of the globe, increasingly reflects a burgeoning realization that fisheries management policies affect not only fishermen, but also the broader communities in which fishermen work and reside. Understanding fishing communities, however, is not a straightforward task. Researchers draw upon many methodologies across diverse disciplines in the attempt to better understand the needs of fishing communities and the ways in which fisheries management programs affect these communities. This special issue draws together international research on fishing communities, highlighting the diverse relationships between people, places and their fish and fisheries. Rather than attempting to consolidate these complex, multifarious relationships into simple metrics, the papers presented in this issue illuminate community needs and wants from a variety of frameworks highlighting the importance of meaningfully understanding local contexts. These papers represent novel frameworks and case studies, adding depth of scholarly knowledge to a relatively understudied segment of fisheries management. Specifically, the goal of this issue is to advance the inclusion of community considerations in fisheries management processes. While approaching the topic of fishing communities from diverse perspectives, the papers in this special issue work together to provide a broad view of the concerns and conflicts existent in these communities. They highlight the need for management endeavors to be flexible, broad, and inclusive, providing potential tools and frameworks to aid in management projects.  相似文献   
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