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中国建立国家公园的目的是保护自然生态系统的完整性和原真性, 促进生物多样性保护。国家公园的完整性和原真性评价是国家公园的布局规划、边界范围确定以及功能区划等研究的前提条件。为了评估国家公园自然生态系统完整性和原真性状态, 本文基于陆地自然生态系统的结构和功能, 通过指标筛选、专家咨询、指标量化和建立综合评价模型, 构建了陆地自然生态系统完整性与原真性的评价指标体系及其量化评价方法。该评价方法包括5个自然生态系统完整性指标、5个自然生态系统原真性指标和2个综合评价指标。以浙江省钱江源国家公园体制试点为例, 本文初步评估了其生态系统完整性与原真性状态, 并对评价结果进行了分级。按照本研究的评价方法, 钱江源国家公园体制试点的自然生态系统完整性评价结果为52.83%, 评价等级为较差; 自然生态系统原真性评价结果为87.06%, 评价等级为好。钱江源国家公园体制试点有待关注和提升的指标有保护区域完整性指数(27.00%)和旗舰种适宜生境完整性指数(53.04%)。最后, 本文结合研究区域评价结果对生态系统完整性和原真性领域应关注的问题进行了讨论。该自然生态系统完整性和原真性评价方法可提供一种评价指标覆盖较全面、数据易获取, 且评价结果易被决策者和管理者理解的评价思路。  相似文献   
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Background and Aims

Preservation of cultivar purity creates a particular challenge for plants that are self-incompatible, require insects for cross-pollination, and have easily germinating seeds and vigorously spreading rhizomes. As the fields must be planted with mixed populations, and a balance must be maintained between the cultivars to achieve effective pollination, methods for field monitoring of the relative density of different cultivars must be practical. Furthermore, a DNA-based method is needed for cultivar verification in the collections and outside of the growing season. The aim of this study was to develop both types of methods for Rubus arcticus (arctic bramble).

Methods

Morphological parameters were measured from six cultivars grown on three farms. Observations from the flowers and fruits included: petal and sepal number, flower diameter, arrangement of petals, size of calyx in relation to corolla, fruit weight, yield and soluble sugars. Observations from the leaves included: width and height of middle leaflet, shape of the base of terminal leaflet, shape of terminal leaflet, leaf margin serration and fingertip touch. The applicability of simple sequence repeat (SSR) or microsatellite DNA markers developed for red raspberry was tested on eight arctic bramble cultivars.

Key Results and Conclusions

Morphological and molecular identification methods were developed for R. arcticus. The best morphological characteristics were the length-to-width ratio of the middle leaflet and leaf margin serration. A particular characteristic, fingertip touch, was shown by electron microscopy to be related to the density and quality of the leaf hairs. Red raspberry SSR marker no. 126 proved to be applicable for differentiation of the eight arctic bramble cultivars tested. These identification methods are critical to secure the maintenance and management of R. arcticus. However, the challenges faced and approaches taken are equally applicable to other species with similar biology.  相似文献   
4.
A ‘new Irish’ American ethnicity surfaced in the 1980s – according to a number of scholars and journalists – and is comprised of what some consider to be more ‘authentic’ and ‘traditional’ Irish cultural attributes. Defining authentic and traditional Irishness is complicated, however, by the recent influx and highly visible forms of economic capital and media attention stemming from the Celtic Tiger – the surge of economic prosperity that began in Ireland in the 1990s – and the commercializing of Irish music and dance – such as Riverdance. In this paper, I propose, through my study involving Irish language enthusiasts, that this ‘new’ form of Irish ethnicity is more the result of rather than the reason for this surge in popularity. I use Pierre Bourdieu's ‘Forms of Capital’ in questioning the ‘new Irish’ American ethnicity, arguing instead that a deeply seated, less-visible reservoir of cultural and social capital form the basis for this perceived contemporary ethnicity.  相似文献   
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Anthropological accounts of Vanuatu's independence have emphasised both the materiality of land alienation and the importance of kastom (custom) as a symbol of cultural practice, political resistance and national unity in accounts of decolonisation and postcolonial nation‐making. For 74 years indigenous ni‐Vanuatu were stateless and lacked all forms of citizenship and nationality in the Anglo‐French Condominium of the New Hebrides (1906–1980). This article situates anthropological accounts of land, kastom and the state in Vanuatu's transition to independence in relation to statelessness, citizenship and hierarchies of ethnographic authenticity within the geo‐classificatory frameworks of colonial rule established by the condominium. The embodiment of citizenship and demands to end the cumulative humiliations of statelessness that ni‐Vanuatu experienced in the condominium illuminate both tensions and continuities in idealist and materialist accounts of Melanesian nationalisms evident in kastom and land as they were mediated by the emancipatory claims and promises of postcolonial citizenship.  相似文献   
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古代DNA研究实验技术   总被引:5,自引:1,他引:4  
杨淑娟  赖旭龙  唐先华  盛桂莲 《遗传》2002,24(5):551-554
现代分子生物技术的发展,使从古代样品中获取微量DNA成为现实。在过去的十多年里,古DNA研究取得了重大进展,但实验方案还需要加以改进,其结果的分析与推论也需要多方面的验证。本综述着重介绍了古DNA研究的实验技术及可靠性分析。 Experimental Techniques for Ancient DNA Research YANG Shu-juan1,LAI Xu-long1,2,TANG Xian-hua1,SHENG Gui-lian1,2 1.Faculty of Earth Sciences,China University of Geosciences,Wuhan,430074,China; 2.Institute of Life Sciences,China University of Geosciences,Wuhan,430074,China Abstract:The development of modern molecular biological techniques makes it possible to study minimum DNA from ancient materials.During past decade,a lot of significant achievements on ancient DNA research have been made in many fields especially in molecular evolutionary biology.The nature of degradation and contamination of ancient DNA from ancient biological materials pose a dominating problem in ancient DNA research.Therefore,the experiments should be modified based on the modern molecular techniques and more factors should be considered when the results are analyzed.In this paper,authors review the general experimental protocols on sampling,extraction and amplification as well as authenticity of ancient DNA. Key words:ancient DNA;authenticity;ancient DNA techniques  相似文献   
7.
This paper introduces the concept of strategic ethnic performance (SEP), when members of one ethnic group present themselves as members of a phenotypically similar ethnic group for economic gain. I use ethnographic and interview data focused on Sub-Saharan African merchants involved in the Hip Hop fashion boutique business in urban Japan to show how SEP develops from four interconnected areas: the opportunity structure for ethnic entrepreneurs, the physical presentation of sellers, the arrangement of the selling venue, and feedback loops between the seller and the consumer. By utilizing SEP, ethnic entrepreneurs enhance the perceived authenticity of their goods and themselves. A thorough analysis of this process illuminates the interactional nature of ethnic authenticity as it is understood by consumers within urban areas.  相似文献   
8.
Over the past 60 years, the phenomenal growth of international tourism has been paralleled by the phenomenal growth in festivals held across the world and the increasing academic attention given to understanding them. Performances of culture in tourist settings are often viewed as inauthentic, staged purely for the benefit of tourists. This article contests this enduring perspective, best known through the notion of ‘staged authenticity’. Drawing on research conducted in the diasporic Pacific festival space in New Zealand, this article focuses on how those from within Pacific communities view their performances. Giving agency to the actors allows them to define performances and festivals from an emic perspective, and this challenges the notion of staged authenticity. Rather than material performed purely for the festival and its cultural tourists, performances instead represent a movement of material from largely homogenous community contexts into the multicultural public sphere. Furthermore, the notion of nonlinear temporal relations shows how these performance traditions function contemporaneously, as an important component of the community repertoires from which they come. This in particular challenges the idea that touristic performances represent ‘staged authenticity’. Rather, traditional musics represent one way in which diasporic Pacific communities authentically stage themselves.  相似文献   
9.
Cyril Schafer 《Ethnos》2016,81(5):759-791
Current thanatology discourse details a new ethos of openness transforming death-related practices, accentuating a shift to personalised rituals, authenticity and expressive grief. Drawing on ethnographic interviews with mourners and funeral professionals, this article explores these putative post-mortem changes and critically assesses the claims and counterclaims concerning funerary arrangements in New Zealand. While underscoring the complexity of mortuary practices, this study explicates the varying notions of authenticity that pervade the funeral discourse. Although funeral professionals emphasised the significance of grief and bereavement processes characterised by a need for honesty and transparency, bereaved participants proffered an alternative interpretation of authenticity that privileged biographical coherence and the need to confer transcendence to the dead. These findings not only emphasise the inadequacies of the aforementioned representations of post-mortem change, but elucidate the context-specific conceptualisations of authenticity and the continuing relationships between the living and the dead in Aotearoa/New Zealand.  相似文献   
10.
百合远缘杂交育种及其真实性鉴定   总被引:3,自引:0,他引:3  
以5种野生百合与2个杂种系百合品种为亲本,设计6个杂交组合进行远缘杂交,通过子房与田间培养成功获得远缘杂交种并采用形态学与RAPD分子标记对其真实性进行综合鉴定。结果显示,杂交组合麝香百合?条叶百合通过子房培养获得杂交苗3株;条叶百合?王百合、条叶百合?‘雪皇后’、细叶百合(黑龙江种源)?‘雪皇后’、 细叶百合(黑龙江种源)?‘西伯利亚’与细叶百合(承德种源)?‘西伯利亚’各杂交组合均获杂交种子,结籽率分别为27.0 %、1.4 %、31.5 %、0.04 %与0.08 %。杂交种株型在苗期表现为偏母植株与中间型植株,其他形态学指标介于亲本之间或优于亲本;RAPD分子标记鉴定表明,杂种植株既扩增出相加性带型、单亲本带型,又扩增出融合双亲的特异性带型。获得杂交种为真杂种可用于百合品质育种。  相似文献   
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