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11.
Roman plasters sampled from different houses at the archaeological site of Herculaneum, Italy, (2010–12) were studied by means of petrography, thermal analysis and X‐ray fluorescence. Herculaneum plasters are composed by preparatory layers (arriccio) with a thickness of several centimetres and are based on a calcitic binder and volcanic scoriae as aggregates, covered by a thin final layer characterized by a low granulometry. Most of the sampled plasters can be placed into two groups based on the aggregate composition and classified as marmorino or intonachino. However, a similar aggregate composition did not induce superimposable thermal behaviour, thus suggesting that the samples underwent different ageing/weathering processes, with a consequent change of the ratio among the components.  相似文献   
12.
Zoos and aquariums are responding to the worldwide biodiversity crisis through major conservation initiatives like captive breeding for assurance populations and reintroduction programs. These institutions also fundraise, offer education programs, and provide critical research on biodiversity. Through a case study inside three accredited Canadian zoos, this paper illustrates that zoos and their staff members are being incorporated into many official species‐at‐risk recovery efforts on provincial, federal, and international levels. Specifically, the zoos studied are involved in every stage of the recovery process, from providing valuable research and habitat analyses, to captive breeding animals for reintroduction, to writing recovery strategies and creating recovery policy for multiple jurisdictional levels. Zoo staff indicate that zoos are uniquely suited to conservation because zoos have space, expertise, apolitical status, and the ability to connect with the public. Overall, the paper suggests that zoos can significantly contribute to species‐at‐risk protection and recovery in Canada and beyond.  相似文献   
13.
ABSTRACT

This special issue contains eight essays on the liturgy celebrated in the Latin East in the twelfth and thirteenth centuries. The papers as a whole demonstrate how the study of the liturgy can open up the religious and cultural history of the crusades and the Latin Kingdom of Jerusalem, reveal crusade spirituality and practice, and trace how the Latins of Outremer expressed through their liturgy their historical consciousness and awareness of contemporary realities.  相似文献   
14.
Since the early 1990s, nature conservation organizations in Eastern and Southern Africa have increasingly attempted to integrate their objectives with those of international development organizations, the land-use objectives of local communities and the commercial objectives of tourism businesses, in order to find new solutions for the protection of nature and wildlife outside state-protected areas. The increased inclusion of the market in conservation initiatives has led to diverse institutional arrangements involving various societal actors, such as private game reserves, conservancies and conservation enterprises. The Koija Starbeds ecolodge in Kenya – a partnership between communities, private investors and a non-governmental organization – serves as a case study for emerging institutional arrangements aimed at enabling value creation for communities from nature conservation. Based on a content analysis of data from individual semi-structured interviews and focus group interviews, as well as a document and literature review, this article reveals a range of benefits for community livelihood and conservation. It also identifies a range of longer term governance challenges, such as the need to address local political struggles, the relations between partners and transparency and accountability in the arrangement.  相似文献   
15.
旅游者对旅游目的地的形象认知是影响旅游活动的重要因素,对旅游目的地形象定位和市场营销策略的选择都具有重要的参考价值,逐渐成为旅游研究的新热点。本文选取了我国几个代表性的案例,逐步展开分析,提出若干个相应的假设,据此设计了调查问卷,在兰州、西安两地开展了抽样调查。本文应用国际通用的科学方法和规范模式对抽样调查结果进行分析,根据分析结果对旅游者对旅游目的地形象认知中的“先入为主”与“既成事实”效应进行了探讨,强调了旅游形象定位与市场营销中的先发优势。  相似文献   
16.
20世纪90年代以前美国环境史研究的特点   总被引:3,自引:0,他引:3  
高国荣 《史学月刊》2006,8(2):105-114
在20世纪90年代以前,美国环境史研究具有以下三个特点:就研究范围而言,研究的主要问题都属于自然保护和资源保护的范畴,荒野研究成为美国环境史研究最鲜明的特色,而城市及人工环境则未受到应有的重视。其次,从价值取向上说,环境史研究具有显著的环境保护主义的道德和政治诉求。环境保护主义既使环境史受益,使环境史具有鲜明的文化批判意识,同时,它也限制了环境史的未来发展。最后,环境史研究具有比较明显的时空特点:就时间而言,它研究的主要是近现代;就空间而言,美国环境史优先研究的地域首先是西部,其次是东北部,最后是南部。  相似文献   
17.
Rock art conservation has developed hand-in-hand with the increased pace of tourism, yet the two activities tend to remain in opposing camps. Policies and guidelines have been developed for cultural heritage and cultural tourism and there is a widely accepted range of principles in place, but a theory of sustainable rock art tourism is only in its infancy. To mature, the discipline needs research into the interaction of key elements that affect the long-term conservation of frequently visited rock paintings and engravings in their original setting, as well as consideration of social and economic factors that drive tourism and the public interest in rock art.  相似文献   
18.
Economic globalisation has led to a huge increase in demand for food, goods and services by expanding urban middle class populations. These demands cause environmental changes that in turn feed back upon the urban environment and human population. While the global changes are well researched, the cumulative significance of local environmental changes is less well known. Yet, the local changes may have greater impact on the decisions which individuals make that affect soil erosion and land degradation. People respond to family circumstances and to local economic opportunities in ways that most suit the needs of their families and households. Several demonstration projects that were not adopted offer lessons in understanding how people make their land‐use decisions. An understanding of people's past experiences, present needs and views of the future helps those seeking to improve environmental management to promote policies and actions that are likely to succeed by being acceptable to those involved.  相似文献   
19.
青海喇家遗址出土人骨的现场保护   总被引:4,自引:3,他引:1  
为保护青海省民和县喇家村史前灾难遗址现场,对4座房址中出土的21具人骨进行了原地的加固和保护。根据人骨的保存状况及其埋藏环境的调查情况,在加固材料对比实验的基础上,选取三甲树脂的二甲苯和丙酮(溶剂体积比6:4)的混合溶液,采用多次缓慢滴注的办法进行加固处理。结果表明,滴渗法对脆弱的骨头具有良好的加固效果。  相似文献   
20.
《宋太祖实录》前后经过四次编修,成书三部,至迟到元代时仍有传本存世。其纪事由于皇帝直接干预以及史臣避忌等原因,从而始终存在缺漏、原无后增以及与它史有异等问题,它直接促使私家通过著述欲辨明该段史事。  相似文献   
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