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11.
Questions of mobility, settlement pattern, and their relation to economic organization and resource use are central to ongoing work in central-western Argentina. Here we analyze geographic patterns in the distribution of 178 human bone carbonate δ18O samples, 46 human tooth enamel carbonate δ18O samples, and 48 water δ18O samples from throughout the Andean Cordillera and Monte Desert and evaluate their implications for prehistoric mobility and economy. We confirm and refine previous generalizations regarding a highland/lowland dichotomy in water δ18O values and show that the range of human carbonate δ18O values generally reflect available water sources. While there is little within-lifetime change in patterns of water use, we show that most individuals have stable isotope signatures consistent with water use from multiple areas or areas other than where they were ultimately interred. These data indicate high levels of residential mobility, and we conclude by discussing their implications for our understanding of regional prehistory.  相似文献   
12.
Organic fertilizers have the capacity to alter the nitrogen isotopic composition of plants. Camelid dung and seabird guano are two potentially important fertilizers in the agricultural systems of western South America, particularly Peru and Chile. This paper presents isotopic data (δ13C and δ15N) from field grown plants (maize, Zea mays) fertilized with the following four treatments: CO (control, no fertilizer applied), AS (ammonium sulfate, a chemical fertilizer), DU (camelid dung), and SG (seabird guano). Plants were grown in experimental plots in the Virú Valley, northern Peru. Plants fertilized with the chemical fertilizer presented very similar isotopic compositions compared to the control. Conversely, the camelid dung fertilized plants were characterized by higher δ15N values compared to the control plants (by 1.8 to 4.2‰ depending on the plant part). The seabird guano fertilized plants were greatly enriched in 15N in comparison to the control plants (by 11.3 to 20.0‰). The results of this study have important implications for the reconstruction of human diet using isotopic data derived from bone collagen and related tissues, particularly in the prehispanic Andes, but also in Europe and North America during the 19th century, when Peruvian seabird guano was used extensively. Specifically, the interpretation of the relative contributions of plant and animal protein to the diet on the basis of bulk isotopic compositions of bone collagen (or similar tissues) may be confounded by camelid dung fertilization if the carbon isotopic compositions of the two sources are similar. Likewise, the interpretation of the relative contributions of maize and marine protein may be confounded by seabird guano fertilization.  相似文献   
13.
The 12th-century depopulation of large villages in the Mimbres region of the US Southwest has been attributed to a number of causes, including resource stress. This study combines archaeological evidence and models of environmental conditions in the eastern Mimbres area of southwest New Mexico to assess the magnitude and timing of food stress from a combination of a period of reduced precipitation and the effects of prolonged hunting and farming activities on the landscape. Results indicate that large game in the area was quite sensitive to hunting pressure, and was locally depleted long before settlement reorganization occurred. Access to arable land was somewhat reduced around the time of settlement reorganization, but productive land remained locally plentiful. Although the settlement reorganization did not improve access to large game or arable land, farmers’ perceptions of below-average conditions for agriculture relative to their expectations and past experience would have contributed to decisions to move.  相似文献   
14.
Abstract

The results of an analysis on plant remains (fruit, seeds, pollen and wood) found in sediments in a Roman well in Vada Sabatia (Vado Ligure, Liguria, Italy), dated between the first and fourth centuries AD are presented. The remains are well preserved and constitute an exceptional record of the Ligurian area. Five layers have been recognised: three corresponding to the well when in use and two to the well when it was no longer in use. The vegetational cover of the area has been found to be similar to that observed in the coastal plain near Albingaunum (Albenga) pertaining to the same period. Moreover, the two superficial layers have cumulated a large amount of macroremains related to the period in which the well was no longer in use. The principal tree and vegetable crops and cereals of the coastal plain were present, due to the influence of maritime and mercantile trade, as were the prevailing ruderal and weed species and the tree cover. The presence of carpological remains of Castanea sativa, Secale cereale, Beta vulgaris and Cucumis sativus is reported for the first time in the Roman Age in Liguria. The influence of the arrival of the Romans can be seen from new crops, such as Prunus persica, and the introduction of exotic fruit like Phoenix dactylifera and Ziziphus jujuba. Several wooden artefacts, for example, a rack for drying lucerne and a tool handle, made of Cornus or Viburnum and Viburnum cf. lantana respectively, have been found. The well has proved to be an ideal location for the preservation of plant remains compared with other studied archaeological situations in Liguria and in Southern France, as it presents a higher variety of cultivated fruits, vegetables and cereals.  相似文献   
15.
Despite decades of efforts to curb the global supply of illicit drugs and significant shifts in how those efforts are designed and implemented, illicit crop cultivation persists. In this paper, we examine state and international development efforts to eradicate coca in Peru, opium poppies in Laos, and cannabis in California, USA and the ever-changing discourses used to justify and design these interventions. Scholarship in political geography frames eradication interventions as serving ongoing efforts to extend state and market power into the regions in which illicit crops are grown and to marginalize the people growing them. We find that environmental discourses are increasingly used to assert the need for continued illicit crop interventions, and that these discourses articulate with historical and ongoing portrayals of smallholders as environmentally destructive. Environmental harm narratives that justify enforcement and eradication efforts under the guise of protecting ecosystems from illicit crop farmers can become self-fulfilling prophecies when they disproportionately impact smallholders and push them into marginal geographic and economic positions. Our cases illustrate that environmentally-justified interventions drive cycles of marginalization for illicit crop smallholders, often conditioned by race or ethnicity, who are then portrayed as environmental criminals. Meanwhile, new state-sanctioned spaces of opportunity and profit are created for more powerful actors who are able to capitalize on the removal of illicit crop growers from the land.  相似文献   
16.
A review of archaeobotanical data, together with new, still unpublished data, from Roman sites in conventus Bracaraugustanus suggests the Romanization of the northwest Iberia brought little changes to the agricultural strategies of local communities in indigenous-type settlements. The main crops remain the same as in the Iron Age: Triticum aestivum/durum, Panicum miliaceum, Hordeum vulgare subsp. vulgare, Triticum turgidum subsp. dicoccum and T. aestivum subsp. spelta, Avena and Vicia faba. The first secure reference for the cultivation of Secale cereale in the region comes from a Roman context, suggesting that it was introduced in this period, although it probably remained a minor crop.  相似文献   
17.
中国最早的稻作与稻作农业起源中心   总被引:2,自引:0,他引:2  
产生最早稻作的地方未必一定能成为稻作起源的中心,中国最早的稻作可能在华南北部诞生,中国稻作农业起源的中心首先是在长江中游,长江下游和淮河上游也可能是另外的两个中心。  相似文献   
18.
闵小芳 《攀登》2006,25(3):68-70
本文对青海省农牧业现状以及在结构调整中存在的突出问题进行了初步分析,针对这些问题,围绕进一步加大结构调整力度,提出了一些建设性意见。  相似文献   
19.
Based on qualitative research conducted in Chikwawa and Phalombe in Malawi, this article discusses how gender relations shape men and women’s access to and participation in agricultural training. It also examines how men and women justify or challenge gender inequalities in relation to access to agricultural information and knowledge. Data on gender and recruitment to and participation in training, barriers to training and access to information as well as farmer to farmer extension models were collected and analysed. A gender relations approach, focusing on power and inequality, was used to analyse the data. The data shows that the perception of men as household heads and women as carers or helpers who are also illiterate and ignorant often has implications on women’s ability to access training and information. Negative stereotypical perceptions about women by their husbands and extension workers militate against women’s access to training and information. Institutional biases within extension systems reproduce gender inequality by reinforcing stereotypical gender norms. Extension officers should be targeted with training on gender responsive adult learning methodologies and gender awareness to help them be more inclusive and sensitive to women’s needs.  相似文献   
20.
Abstract

The global phenomenon of the birth of agriculture remains an enigma and challenges the role of food storage. Much has been written about their invention. A general explanation is needed for its progression in various parts of the world, which is both sociologically based and founded on the archaeological data. This task led Alain Testart to claim that it was by developing their existing skill sets (foraging, pottery, food storage and small-scale agriculture) that nomadic hunter-gatherers, burdened by an increasingly diverse set of tools and equipment, became sedentary. This sedentarism in turn allowed them to specialise in those activities, which had (literally) weighed them down: notably, breeding the first plant cultivars and, often, storing food.  相似文献   
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