首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   21篇
  免费   0篇
  21篇
  2024年   1篇
  2018年   2篇
  2016年   1篇
  2015年   1篇
  2014年   2篇
  2013年   9篇
  2011年   1篇
  2010年   2篇
  2006年   1篇
  1992年   1篇
排序方式: 共有21条查询结果,搜索用时 0 毫秒
1.
The analysis of environmental archives from across the world has demonstrated that human perturbation of the geochemical cycles of trace metals and the resultant atmospheric metal contamination date back, at least, several millennia. However, an understanding of the local processes and timing of changes in trace metal deposition is also essential for a proper global interpretation. The Iberian Peninsula was a major mining area since prehistoric times and the analysis of environmental archives provides a good opportunity to improve our understanding of the history of mining and metallurgy in Europe. We present the results from three 14C dated peat cores from the Xistral Mountains (NW Iberia). These records are used to reconstruct past atmospheric deposition of Ni, Zn, As, and Cd. The chronology of the changes in concentrations and metal accumulation rates was found to be concordant in the three bogs, and showed great similarity to total Pb, Hg, and Pb isotope ratios as determined in previous investigations. They present a consistent view of changes in atmospheric pollution and the importance of metals in the development of human societies, especially: i) the first evidence of atmospheric metal pollution 3400 years ago, which is simultaneous with the expansion of the Atlantic Bronze Koine; ii) a pollution event between 2350 and 2150 years ago, associated to the development of so-called Celtic culture (local Late Iron Age); iii) a dramatic increase of metal fluxes in Roman times; iv) a severe and rapid increase in the last 250 years corresponding to the beginning of the industrial revolution in Europe, reflecting the emergence of the new dominant sources of pollution, and v) the increase of long range atmospheric transport of pollutants. Our data suggest that all detected ancient (until ca. 1450 cal BP) periods of enhanced Ni, Zn, As, and Cd accumulation may have had an anthropogenic origin, related to the onset and development of mining and metallurgy.  相似文献   
2.
Despite an increasing number of publications regarding the Pre-Columbian earthworks of the Llanos de Moxos, there have been no serious attempts to undertake a systematic survey of the archaeological remains of this lowland region in the Bolivian Amazon. Based on the GIS analysis of data gathered in the field and retrieved from satellite images, we discuss the spatial distribution of the Pre-Columbian settlements in a 4500 Km2 area of the Llanos de Moxos to the east of Trinidad, capital of the Beni Department, and their relationship with the geographical settings. Our findings shed new light on the prehistory of the region and bear important implications for our understanding of the impact of Pre-Columbian human occupation.  相似文献   
3.
Recent studies have shown that pre-Columbian societies in the Amazon undertook significant landscape modifications, including earthworks. Our fieldwork has revealed that pre-Columbian settlements in the Santarém Region, Lower Amazon, were not limited to the vicinities of permanent water courses, as formerly often assumed. Instead, numerous archaeological sites, dating from ca. a.d. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém. These upland sites have been found to be associated with particular features in the landscape: cavities or depressions, known locally as “Poços de Água”. LiDAR data shows that a pattern of non-randomly distributed depressions extends far into the densely forested Tapajós National Forest (Flona-Tapajós), allowing us to suggest that the expansion of inland settlement extended considerably farther to the south than what has previously been established through conventional archaeological fieldwork.  相似文献   
4.
    
Vikram Tamboli; 《对极》2024,56(1):299-327
This article enriches the narrative of ethno-racial politics in Guyana by analysing the lives and histories of people who live and work in the Guyanese Northwest. It narrates how histories of escape, freedom, and fortune—along with the associated development of the Guyanese interior as an extractive space—were essential to understanding the broader forces that shaped working peoples’ mobility in the region. Using a combined method of conducting oral history, memory analysis, ethnography, participant observation, and archival research, the article demonstrates how histories of mobility (or lack of) and notions of being Black produced—and were produced through—the gendered historical politics of socio-cultural mixture. The borderland space between the Caribbean and Amazonia, this article argues, helps deepen and recontextualise aspects of the divisive political history of Guyana.  相似文献   
5.
The Llanos de Moxos (LM), Beni, Bolivia, with its impressive number of pre-Columbian earthworks, is an ideal region for studying past human–environment interactions in the Amazonia. Agricultural raised fields are among the most striking of those earthworks. They can offer us valuable information about the region’s agricultural carrying capacity and the nature and extent of human occupation in pre-Columbian times and, therefore, help adopt better informed conservation and development strategies for Amazonia in the future. However, before tackling these issues we need to further our understanding of why pre-Columbian raised fields were built and how they were managed in the past. Published data on raised fields in the LM is contrasted with new data gathered from field and remote sensing images. Raised fields have been analysed in relation to the hydrology, soil, topography and paleoclimate of the areas where they are found. In light of this new data we believe that there are grounds to question the current model that suggests raised field agriculture provided high yields without the need of fallow periods, representing a kind of pre-Columbian green revolution. Our alternative proposal suggests that raised field agriculture allowed pre-Columbian peoples to mitigate the risk of more intense and frequent flooding than is experienced today in the LM. We show that raised fields were built only in those areas where there were no alternatives, which do not coincide with those areas where pre-Columbian societies seem to have flourished and reached high levels of social complexity.  相似文献   
6.
Carlorosi, J., Heredia, S. & Aceñolaza, G, 2013. Middle Ordovician (early Dapingian) conodonts in the Central Andean Basin of NW Argentina. Alcheringa 37, 1–13. ISSN 0311-5518.

This paper describes and analyzes the significance of a conodont fauna from the Alto del Cóndor Formation, exposed in the Los Colorados region of the Argentine Eastern Cordillera. Identified taxa are Baltoniodus triangularis, Baltoniodus sp. cf. B. triangularis, Drepanodus sp., Drepanoistodus basiovalis, Drepanoistodus sp. B., Erraticodon patu, Gothodus costulatus, Oistodus sp., Trapezognathus diprion, T. quadrangulum, Triangulodus sp. and Triangulodus? sp. The presence of Baltoniodus triangularis indicates the base of the Dapingian stage (Middle Ordovician). In addition, we report the coexistence of T. diprion and T. quadrangulum. The conodont association suggests a faunal affinity with Baltica and South China, both belonging to the Shallow-Sea Realm of the Temperate-Cold Domain.

Josefina Carlorosi [josefinacarlorosi77@gmail]com], INSUGEO—Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Guillermo F. Aceñolaza [acecha@webmail.unt.edu.ar], Universidad Nacional de Tucumán—CONICET, Miguel Lillo 205, (4000) Tucumán, Argentina; Susana Heredia [sheredia@unsj.edu.ar], CONICET–CIGEOBIO and Instituto de Investigaciones Mineras, Facultad de Ingeniería, Universidad Nacional de San Juan, Urquiza y Libertador, (5400) San Juan, Argentina. Received 22.8.2012; revised 18.10.2012; accepted 24.10.12.  相似文献   
7.
    
We describe an incomplete trunk vertebra of a snake attributable to the Viperidae, collected from a conglomerate facies in upper Pleistocene sediments at the Mississippi locality, Upper Juruá River, southwestern Brazilian Amazonia. It represents the first fossil snake record from the Pleistocene of this region. This specimen extends the fossil distribution of the Viperidae, representing the northernmost record of a snake in the Brazilian Pleistocene.  相似文献   
8.
Through multiple stories about Shajaó, an untold history of the Peruvian Amazon unfolds. This article, based on extensive archival research and fieldwork, brings together multivocal accounts about an Ese Eja man who allegedly killed a Catholic priest in 1932 and who, despite the large-scale expeditions sent out to capture him, was not apprehended until 1942. Through ongoing tales of Shajaó, the intersubjective ways in which memory is shaped and employed to influence and make sense of sociopoltical contexts is revealed in the exchanges between a notable “savage” and various economies in different historical settings—the rubber boom, extractivism upheld by debt-peonage, Catholic missionization and today's environmental service economy. This exploration questions the construction, reproduction and transformation of the multiple, though not always shared, experiential and interpretive frameworks that shape the historical consciousness of individual and collective memories over time. It also suggests that “disremembering”, in archival and oral accounts, reflects a critical political awareness of history's valid flexibility. Here, narratives are rewoven so that history continues to be told in ways that ensure that “Shajaó stories” never truly end.  相似文献   
9.
    
Terrestrial reptile remains are very rare in the Lower Cretaceous of South Australia, but include the holotype of the small theropod Kakuru. Here, we review this taxon and other archosaur specimens collected from the Bulldog Shale (Aptian) of Andamooka and Coober Pedy. Kakuru possesses no unique characters or character state combinations and is regarded as a nomen dubium, representing an indeterminate tetanuran theropod. Two other specimens (a left metatarsal and astragalus) can be referred to Dinosauria, but the identity of several other specimens (phalanges and a centrum) can only be resolved to the level of an indeterminate archosaur.  相似文献   
10.
    
This paper discusses the problems with sampling materials and sampled contexts in the framework of radiocarbon dating of Mesolithic sites situated in generally dry, acid and bioturbated coversand deposits within north‐western Europe. The case studies presented all relate to the coversand regions of northern Belgium and the Netherlands, two areas for which very large sets of radiocarbon dates performed on different organic components are currently available. The study points out that charred hazelnut shells from surface hearths and charcoal from hearth pits guarantee the most secure dating results, while the dating of calcined bones and food crusts from Final Mesolithic pottery so far remains problematic.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号