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排序方式: 共有133条查询结果,搜索用时 2 毫秒
1.
Brooke Kapeller Ryan Plummer Julia Baird Marilyne Jollineau 《The Canadian geographer》2023,67(3):337-351
Environmental stewardship—a concept that describes the relationships between humans and the environment—is gaining increased attention as an approach that can address planetary sustainability issues. In-depth empirical investigations of local environmental stewardship are needed to understand how social-ecological context influences stewardship, as well as the arrangement of conceptual elements in applied settings. This study addresses these needs by conducting an in-depth exploration of environmental stewardship in the Niagara Region of Canada. A single embedded case study design is employed, with environmental stewardship initiatives constituting the individual units of analysis with the case. Analysis of the spatial arrangement of a total of 89 initiatives indicated that initiatives tended to cluster closer to the Niagara River and in more populous municipalities. The significance of collaboration, tensions between the environment and economic development, and concerns about political impacts emerged as themes across contextual factors. The configuration of stewardship elements reveals interesting discrepancies between initiatives and previous stewardship research focused on larger scales, individuals, and organizations. Further analysis is encouraged to illuminate environmental stewardship in other settings as well as advance relational understanding of conceptual elements. 相似文献
2.
古铜矿遗址围岩表层有害生物的防治 总被引:3,自引:0,他引:3
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。 相似文献
3.
Mauro F. La Russa Michela Ricca Anna Maria Cerioni Maria Grazia Chilosi Valeria Comite Marina De Santis 《International Journal of Architectural Heritage》2018,12(1):114-124
During the last restoration of the Fontana di Trevi -Rome (2014–2015), it has been performed a diagnostic investigation to characterize the materials used to build and obtain the colors of the surfaces of some architectural elements of this fountain. According to the restoration teamwork needs, we focussed our efforts on the dome over the central statue of Oceanus, on the bas-relieves on the sides of the dome, and on the cliff where the water flows. Several samples were collected from these elements and therefore, they were subjected to an analytical approach including infrared spectroscopy, optical and scanning electron microscopy. The achieved results indicated the use of red earth pigments on the dome. The same pigment has been revealed on the bas-relieves, although their colors have an additional contribution due to degraded layers. Samples taken from the cliff showed a complex stratigraphy, although a white scialbo has been identified as original layer, testifying the intentions of the authors in term of color rendering. This information was essential for the restores in order to choose the proper intervention procedure for each investigated surface. The research testified the importance of an integrated diagnostic analysis to preserve the original colours of monuments and building. 相似文献
4.
旅游体验是游客情感价值的累积。旅游体验质量评价是对游客心理累积情感的测度,科学、准确的核算游客体验质量是旅游景区、旅游企业等可持续发展及竞争力提升的重要保障。本文通过对1980-2015年发表于国内外旅游及管理领域重要期刊文献的梳理,从服务质量研究的历史、科学视角及与旅游融合的角度对旅游体验质量评价的研究进展、理论基础等进行系统的回顾,并从体验质量评价的理论视角、思路、特征、类型与准确性、可操作性、应用范围等中观层面,对所梳理出的4类国外主流质量评价范式进行旅游体验哲学视角下的解读、比较分析和总评,最后对该领域未来研究重点进行展望。 相似文献
5.
大营子冶炼遗址位于赤峰市翁牛特旗五分地镇大营子村南侧的大山的北坡上,包含东西两区冶炼遗存。东区冶炼遗存年代较早,至迟在公元前1 400年已开始冶炼活动。铅同位素、微量元素示踪研究显示大营子冶炼遗址东西两区均使用了来自林西县大井古铜矿的多金属共生矿石,直接冶炼铜砷锡三元青铜合金。大营子冶炼遗址东区冶炼遗存的年代测定,获得了迄今为止最早的夏家店上层文化年代测定结果,为探讨辽西地区青铜时代考古学文化的演变提供了新的科学证据。 相似文献
6.
The mensuration of multi‐elemental concentrations from assorted archaeological materials has always required great care and attention to detail to ensure good‐quality data and their ensuing interpretations. Although most suspect data were generated before the wide use of computers, error‐free data are not still a certainty. This paper presents the geochemical rationale for a proposed chemical data‐assessment process, using a globally dispersed collection of ceramic, sediment and lithic data. It is argued that this process can allow archaeologists and archaeometrists to investigate systematically older and current data sets and, if need be, alter them to the reliable values they were originally intended to include. 相似文献
7.
Simon Dalby 《The Canadian geographer》2019,63(1):100-111
Considering recent formulations of geopolitical culture in combination with concerns that environmental change be included in contemporary geopolitical analysis, this paper examines the implicit geopolitical formulations in recent Canadian federal political discourse both in Stephen Harper's Conservative government and the subsequent Liberal administration. Contrasting earth system science ideas about global transformations with Canadian nationalist rhetoric concerning petroleum production and notions of unlimited resource extraction as parts of national identity sharply highlights the contours of Canadian identity. If sustainability is to be taken seriously, the official nationalist formulation will have to be drastically changed, but as the widespread rejection of the LEAP manifesto suggests, such ideas of a sustainable mode of globalization have yet to substantially influence Canadian political discourse, despite the rhetorical support offered to the Paris Agreement on Climate Change by the Liberal government of Justin Trudeau. 相似文献
8.
国家恐怖主义是由政府实施的恐怖主义,法西斯主义则是国家恐怖主义发展到登峰造极的产物.国家恐怖主义具有制度化、公开性和社会化的特点,并具有独裁政治,庞大的镇压机器,镇压性的特务机关,非人道的人身迫害,非战争状态下对大量人口的集体收监、屠杀或迫使其流亡,针对社会知名人士的暴力行为等构成要素. 相似文献
9.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model. 相似文献
10.
C. de la Rúa J. P. Baraybar F. Etxeberria 《International Journal of Osteoarchaeology》1995,5(3):254-264
The remains of the fragmented skeleton of a mature male individual from a Neolithic mass burial (ca. 5000 years BP) are presented. The lesions consist of osteoblastic proliferation and replacement of previously normal haematopoietic tissue. The most affected area seems to have been the iliac blade. So-called ‘seeding’ of tumour tissue has been found in different loci in the femoral neck, sacrum, L4 and scapula. Differential diagnosis points to metastatic carcinoma, most likely from the prostrate gland. In order to support the observations, radiological and histological analyses have been performed. Trace element analyses of tumour and control samples have shown the limited contribution of these data to ascertain the aetiology of secondary neoplasias in buried material. 相似文献