基于孢粉记录研究长白山最近两次火山爆发后的植被演替特征

利用不同时期土壤孢粉组成推断长白山火山爆发后的植被演替规律,还原该区域植被群落变化过程,对于揭示该研究区不同时期植被演替规律具有重要意义.该研究通过对长白山最近两次火山爆发后形成的土壤剖面所含的孢粉组成进行分析,揭示火山爆发后高山带的植被变化特征.结果表明:(1)两次火山爆发后的植被演替具有相似的过程,即孢子植物阶段、...     

树轮数据揭示的强火山喷发对青藏高原地区气候的影响

强火山喷发是影响全球气候变化的重要因素。过去几十年,不同学者基于青藏高原地区树木年轮重建了多条气候变化序列,并依据这些序列研究了全球强火山喷发对青藏高原地区气候的影响。结果表明: 探讨强火山喷发对青藏高原气候影响的树轮序列主要分布在青藏高原东部。利用序列对比法和时序叠加法分析发现,中低纬度的强火山喷发对青藏高原地区温度和干湿变化影响显著,并在强火山喷发后的1～2年内出现降温或者发生干旱,而高纬度的强火山喷发影响较小。此外,连续的多次强火山喷发能导致该区出现年代际的冷期。影响强火山喷发气候效应的因素主要包括火山喷发位置、喷发强度、大气环流等。最后结合国内外研究现状,对未来需要开展的研究方向进行了展望。     

Mentawai’s endemic,relictual fauna: is it evidence for Pleistocene extinctions on Sumatra?

Aim The four Mentawai islands, south‐west of Sumatra, have long been isolated from the remainder of Sundaland, resulting in a high level of endemism. We examined the distribution of 151 species of the Mentawai Islands in Sundaland and assessed various processes that may have resulted in the various biogeographical patterns. Location Southeast Asia, particularly the Mentawai Islands and nearby large landmasses (Sumatra, Java, Borneo and Peninsular Malaysia). Methods We compared the faunal composition of the Mentawai Islands for selected taxa (43 mammals, 92 reptiles and 16 amphibians) with that of the four nearby large landmasses of Sundaland using morphological comparisons and the most recent molecular phylogenetic analyses available in the literature. These comparisons yielded sister taxa, which were used to simulate species absence data for the four Sundaland landmasses under several scenarios to investigate how patterns of species absence could have arisen. Results In contrast to our expectations, several Mentawai species did not have their closest relatives on neighbouring Sumatra, but rather on the more distant Borneo, Java or Peninsular Malaysia. For mammals, the similarity between species from Mentawai and Borneo was greater than that observed between species from Mentawai and Sumatra. We conclude that the relationships represent traces of species historically distributed throughout Sundaland that became extinct in Sumatra during the Pleistocene. For reptiles and amphibians the observed pattern of species absences generally resembled the simulated pattern expected under the scenario of absence rates increasing with landmass isolation, whereas for mammals we observed more species than expected missing from Java and Sumatra, and fewer than expected from Borneo. Main conclusions The potential extinctions on Sumatra probably had two causes: changes of climate and vegetation during the Pleistocene and environmental impacts from the Toba supervolcanic eruption.     

How catastrophic was the end‐Triassic mass extinction?

A review of marine and terrestrial animal and plant fossils fails to reveal convincing evidence of a global catastrophe at the Triassic-Jurassic boundary, although this time marked the final disappearance of ceratite ammonites and conodonts, together with the extinction of most calcareous demosponges; important groups of bivalves and brachiopods went extinct. Because of facies problems, however, there is no stratigraphic section that reveals a clear-cut disappearance over a short distance. Other marine animal groups except perhaps the radiolarians fail to reveal a notable extinction of global extent immediately across the boundary. On the other hand, there was a substantially higher extinction rate among marine animals in the Rhaetian as compared with the previous stage. On the land, the record is equivocal. Dramatic changes across the T-J boundary have been claimed for plants in particular areas, such as eastern North America and East Greenland, but only gradual change has been recognized elsewhere. Similarly, claims of a T-J boundary vertebrate mass extinction have not been supported by others. For the Rhaetian as a whole, however, the turnover rate of reptiles was high. Although much remains to be learned, it seems evident that the fossil record of the latest Triassic is more consistent with a gradual scenario extended over time than a 'geologically instantaneous' impact catastrophe.     

Coetzee on South Africa's Past: Remembering in the Time of Forgetting

As an intellectual figure in South Africa, J. M. Coetzee has consistently engaged with the politics of the past, particularly the contemporary ethical ramifications of the colonial past, alongside the more recent and bitter history of oppression under apartheid. As archaeologists, we aim to excavate these engagements through his novels and essays, particularly his long-standing concerns with the Khoekhoe communities of the Cape. In South Africa today, the tensions between remembering and forgetting are palpable and, in the aftermath of the Truth and Reconciliation Commission (TRC), we suggest that not all forgetting can be cast as therapeutic. Throughout his complex relationships with the nation's history, Coetzee foregrounds the colonial past and reiterates the ethical responsibilities of remembering so that the patterns of the past are not repeated.     

Contagion and Alterity: Kowoj Maya Appropriations of European Objects

ABSTRACT  From initial contact with the Europeans until their conquest (C.E. 1525–1697), the Itza and their political rivals, the Kowoj, dominated Petén, Guatemala. Colonial artifacts at Zacpetén record the initial appropriations of European objects by the Kowoj. All such objects rested in ceremonial contexts, indicating that the Kowoj considered them positive sources of sacred power. The Kowoj were in contact with the Spaniards and knew they were the source of the valued materials; hence, the materials also signified otherness. Social elites frequently retained objects obtained from long distances, even those of oppressive colonial groups, as positive contagion. I argue that the Kowoj incorporated colonial objects into their rites to harness the power of alterity.     

Negotiating Community and Landscape in the Peruvian Andes: A Transconquest View

This article explores how constructs of "community" and "landscape" mediate power relations between households and colonial states. I analyze archaeological and documentary data in a common spatial framework to reconstruct the local-scale negotiation of community and land-use organization during successive colonial occupations by the Inka and Spanish states in the Colca Valley of southern highland Peru. Using GIS-based analytical tools, I present a detailed reconstruction of the land-tenure patterns of Andean corporate descent groups ( ayllus ) registered in colonial visitas from the heartland of the Collagua Province. I then compare these land-tenure patterns to archaeological settlement patterns from the Inka occupation (C.E. 1450–C.E. 1532) and subsequent early Colonial Period occupation up to the forced resettlement of the local populace into compact, European-style reducción villages in the 1570s. This analysis reveals how both Inka and Spanish colonialist projects for reordering and rationalizing local community and land-use organization were met by local understandings and interests that emerged from patterns of land tenure, residence, and the features of the built environment.     

Pattern of dental eruption,skeletal maturation and stress in a Medieval Population from Sudanese Nubia

The present research represents a comparison of dental and skeletal development as a means for determining nutritional stress in a Medieval Christian population from Nubia’sBatn el Hajar. The sample consists of 21 individuals from an early Christian (c 550–750) and 23 individuals from a late Christian cemetery (c mid-16th century) excavated from the site of Kulubnarti, Sudan. Ages at death ranged from 12 to 23 years. For the combined sample, a large majority (70.5%) of individuals had skeletal ages younger than their dental ages. However, a comparison of those individuals that could be sexed revealed that the pattern was not consistent for males and females. Females showed no difference between skeletal and dental age while males showed significant skeletal retardation. This pattern of sex differences is consistent with that observed for modern living children and subadults experiencing nutritional stress. A comparison by cemetry also suggests a reduction in stress from early to late Christian times with later Christians showing a closer correspondence between skeletal and dental ages. While not statistically significant, this apparent reduction is consistent with previous research on the subadult remains.     

Money in Colonial Transition: Cowries and Francs in West Africa

For about five decades, the French colonial government in the Volta region of West Africa failed in its repeated attempts to replace the local monetary form of cowry shells with its own monetary system of francs, largely because of local opposition. This article provides an account of these events and explores the reasons for the opposition and why the opposition was successful. Despite government prohibition, the cowries even acquired increased vitality as they became the main money in the emerging urban market. Government measures were partly motivated by practical difficulties that stemmed from the conflicts that the colonial system and monetary policy generated. The article ends with a critical discussion of how money and the colonial transition are treated in anthropology.