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South Korea experienced below replacement fertility for the first time in 1983, which also marked the point from which fertility rates continued to decline over the next 20 years to reach a low of 1.2 in 2003. In spite of recent pronatalist policies, the fertility rate has remained near this level and has not increased appreciably. The reasons for sustained low fertility in South Korea are complex and solutions remain elusive. One option that has been suggested is reunification with North Korea, which could address the eventual decline in the population and mitigate the increasing proportion of the elderly. Although the conditions surrounding the German reunification experience were vastly different than what Korea will likely undergo, it is informative to look at Germany as a guide to the demographic parameters of reunification. Three projection models for 2015–2050 are presented; even the highest fertility models show that reunification will not be the answer to population restructuring already underway in South Korea as a result of sustained low fertility.  相似文献   
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This paper investigates evidence for subsistence and settlement activities in the Levantine Middle Epipalaeolithic through the application of stable isotope analysis to human and non-human remains from the site of 'Uyun al-Hammam, northern Jordan. In general, bone from the site suffers a high degree of diagenesis and collagen could not be extracted for analysis here. Carbon and oxygen isotopic values from human tooth enamel samples were variable, but within expected values for the Middle Epipalaeolithic, whereas animal carbon and oxygen isotopic values varied widely, most likely due to hydrological and climatological factors. Carbon and isotopic values for the human samples indicated a predominantly C3 plant dietary input, while animal samples appeared to have varying amounts of C4 inputs into their diet. This is the first isotopic analysis conducted on material from the Middle Epipalaeolithic of the southern Levant and, as such, even results constrained by temporal and climatological variants within the region contribute to the overall knowledge of settlement and subsistence strategies during this cultural period.  相似文献   
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This paper uses remote sensing data to document a raised field, chinampa system adjacent to the Postclassic kingdom of Xaltocan in the northern Basin of Mexico. Various forms of landscape information; historic records and maps as well as remote sensing; are considered to understand the chinampa system. The remote sensing data examined include 1950s aerial photographs, Landsat 7 data, and Quickbird VHR, multi-spectral imagery. This article evaluates the utility of each of these forms of data to identify buried chinampa features and integrates them in a GIS to produce a map of Xaltocan's chinampa landscape. Canals of various sizes and hydrological positions comprised the chinampas and integrated the system together. Occupying at least 1500–2000 ha, Xaltocan's chinampa system represents the largest pre-Aztec, chinampa system in the Basin of Mexico.  相似文献   
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Results of analyses of the photoperiod response gene (PPD-H1) and simple sequence repeats (SSRs) in modern landraces of cultivated barley were used as evidence for the mechanism of agricultural spread in Neolithic Europe. In particular, we explored the usefulness of considering adaptive genes as indicators of past selective pressures acting on crops, during their spread through Europe. In some areas, such as the Alpine region, Britain and Scandinavia, we have evidence to suggest that the adaptation of crops to certain climatic conditions may have contributed to the timing of agricultural spread. At the northern fringes of Europe, and in higher altitude locations in central Europe, the introduction of more suitably adapted cereals may have facilitated successful agriculture to trigger agricultural expansion. This research opens up the possibility of investigating other genetic adaptations to climate, which would permit a fuller evaluation of the relative contributions of climate/crop and forager/farmer interactions in the process of agricultural spread.  相似文献   
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This paper presents and tests a model designed to investigate how off-site herd management developed in settled pre-historic societies. The model is constructed from data collected from traditionally raised local sheep, acting as an interpretive link to published data. The modern comparator was small, but plausible results allow modelling of the archaeological data to be explored. Birth seasonality and herding location are identified through modelled patterns in oxygen isotope data in tooth enamel, and diet just before death by microwear in the same tooth. In combination, these allow aspects of seasonal management of breeding, fallow and slaughter herd sections to be interpreted. Novel practices are discussed in comparison local wild sheep ethology. The case study is Neolithic Çatalhöyük (7400–6200 cal BC) in central Anatolia. Its location provided the opportunity for different parts of the landscape to be used for herding, although choice might have been socially constrained. Data are taken from 72 specimens; the results suggest settlement-wide preference for a suite of practices that kept herds within a day of the settlement and that maintained breeding cycle synchrony with optimal resource availability. Chronological analysis suggests birth season manipulation was tried but rejected, whilst hay or cereal fodder was introduced and became increasingly important. It is argued that herding was probably on dedicated pasture on the arable fringes rather than in closer integration on ‘garden plots’, as there is no evidence of field-edge weed diets and little evidence of adjusting the birth season to accommodate the crop cycle.  相似文献   
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