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41.
In the late 1980s, a collaborative effort between Harvard University’s Lower Mississippi Survey and Tulane University’s Center for Archaeology launched a study examining the causes and consequences of subsistence change in the Lower Mississippi Valley. The Osceola Project contributed the first formal study of late prehistoric faunal remains within the Alluvial Plain, becoming the standard against which all subsequent Coles Creek faunal assemblages have been measured. Recent evidence recovered from three sites located in the Eastern Uplands presented the opportunity to compare and contrast vertebrate subsistence in these two distinct physiographic regions. We hypothesize that a clear distinction exists between lowland and upland Coles Creek procurement strategies. This article evaluates this claim by examining species diversity, spatial patterns, and temporal trends evident within an eight-site sample. The results suggest that the primary factor influencing Coles Creek fauna procurement was the immediate environment, and that the composition of Late Woodland period diets may be a reflection of efficiency of effort rather than food access or scarcity. 相似文献
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Daniel J. Mahoney 《Perspectives on Political Science》2017,46(2):87-92
The French statesman Charles de Gaulle was, and remains, something of an enigma. A genuinely great man, at first glance, he seems to tower above mere humanity. In studying de Gaulle's biographies and writings, the statesman and military man eclipses the human being without leaving his human bearing wholly behind. De Gaulle himself emphasized the solitude and sadness that accompanied the burden of human greatness. Yet de Gaulle, the self-described “man of character,” “the born protector,” was also a loving husband, a not terribly demanding or severe father, a faithful Christian, and a French patriot. There were profound limits to his solitude and self-sufficiency. His austere magnanimity coincided with moderation, even benevolence. He loved his country, strove for greatness, and sacrificed something of his private happiness for the public good. He was a complex man and soul, and perhaps a conflicted one. 相似文献
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Daniel Loponte Mirian Carbonera María José Corriale Alejandro Acosta 《Environmental Archaeology》2017,22(3):247-267
We analyse the isotopic values (δ13C, δ15N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ13Cco?=??15.5?±?1.8‰; δ13Cap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ13Cco ?18.2?±?1.7‰; δ13Cap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ15N 11.1?±?0.6‰) compared to the Taquara samples (δ15N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ18O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ18O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ18O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ13C, δ15N and δ18O) suggest human movements between these two ecozones. 相似文献
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Since Marshall (1890), it has been widely held in urban economic theory that cities insure workers against the risk of unemployment by offering a larger pool of potential jobs. Using a large administrative panel data set on workers displaced as a result of plant closures, we examine whether positive effects from a higher urban job density are offset by more intense competition between workers. When controlling for the sorting of workers between regions, we find robust evidence that the effect of job competition on unemployment duration exceeds that of job opportunities in absolute value. Our results put the idea of urban risk-sharing into perspective and provide an explanation for observed longer unemployment durations in cities. 相似文献
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David M. Kennedy Teresa Konlechner Elisa Zavadil Michela Mariani Vanessa Wong Daniel Ierodiaconou Peter Macreadie 《Geographical Research》2018,56(1):80-91
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments. 相似文献
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