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581.
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A pollen diagram was prepared from Lake Almalou, a volcanic crater wetland located on the eastern flanks of the Sahand Volcanic Complex in NW Iran. The core provides a 3700-year record of human activity and environmental change in an upland region. We attempt to relate vegetation changes to both climatic change and historical events. Variations of anthropogenic pollen indicators suggest several phases of intensified human activities. Two strongly expressed agricultural phases are dated at about 2450–2220 cal BP (Achaemenid Empire) and 230–30 cal BP (collapse of Safavid Dynasty to the modern period). Historical rather than climatic events appear to be the main controlling factors for upland land-use dynamics. Fruticulture has been practiced in the region at least since the Iron Age, reaching its maximum importance 1500–1250 cal BP during the reign of Sassanid Empire; it declined by the time of Islamic conquest of Iran (651 AD). The Little Ice Age is tangibly recorded by higher lake water levels most probably due to both lower summer temperatures and higher annual precipitations. Low values of cereal-type and cultivated tree pollen during this period may indicate a change in the lifestyle from the cultivation of fields and orchards to a more nomadic life dominated by summer pasture. The modern period (1850 AD onwards) is characterized by expansion of agricultural activities to upland areas and intensified pastoralism.  相似文献   
585.
This article examines the manner in which the Grosses vollständiges Universal-Lexikon published by Johann Heinrich Zedler from 1732 to 1750 and considered as the most important german language encyclopedia of its time, welcomes and restructures the classical doctrine of the reason of State. Contrary to the interpretation in which the concept of the State developed by the Lexikon would fit into a pure jusnaturalistic logic, it shows the permanence, parallel to wolffian natural law, of a prudential tradition of political thought. The Lexikon, a contemporary of the Anti-Machiavel of Frederic II, thus appears to be the faithful mirror of the heterogeneous tendencies which then illustrate the field of the problems in the reason of State.  相似文献   
586.
Carbon and oxygen isotope values reveal resource partitioning among the large mammal fauna from three contemporaneous Middle Pleistocene hominid-bearing localities within the Sierra de Atapuerca (northern Spain). Carbon isotope values sampled from the tooth enamel of fauna present during Atapuerca Faunal Unit 6 show that a C3-dominated ecosystem surrounded the area where fossils were preserved during this time. For the herbivores, Fallow deer isotope values are significantly different from Red deer and horses and show that this species did not forage in open environments at this locality. Red deer and horses show similar feeding strategies with less negative carbon values implying use of more open environments for these taxa. For the carnivores, carbon isotope values for Ursus deningeri are significantly different from either lions (Panthera leo) or foxes (Vulpes vulpes) and support the contention that this species is herbivorous. Special metabolic mechanisms involved in hibernation in U. deningeri might also have influenced its isotope values. The carbon isotope values of remaining carnivores were similar and suggest that each was typically a generalist carnivore, eating a wide variety of prey items. While the isotopic results generally correspond to ecology indicated by previous techniques, this study shows that isotope analyses can provide further insights that alternate techniques do not provide. Isotope analyses can help elucidate the ancient ecology of taxa present in the Sierra de Atapuerca during the Middle Pleistocene allowing for an accurate portrayal of the setting in which humans lived.  相似文献   
587.
The east Arabian settlements in antiquity were never large urban sites. However, they were the main centres of the communities that inhabited that area, interfacing between the nomadic and sedentary societies. A study of the distribution and characteristics of these sites reveals different, complementary functions. They were organized in local networks forming the essential structure of the settlement pattern and delineating the territories of communities having their own political identity.  相似文献   
588.
Statistical regression models are presented that explain the observed variations, across urban areas, in the concentrations of two major pollutants, ozone and carbon monoxide. Model specification and estimation are based on an explicit and new spatial framework derived from the theoretical concept of well‐mixed cells, whereby the basic Fickian system of diffusion equations is integrated over the regional space partitioned into a grid of large cells. The concentration in each cell results from the balance of pollutant flows into and out of this cell and of pollutant emissions and removal within that cell, and is expressed as the sum of two concentration contributions: (1) the local effect, dependent upon pollution‐related factors around the measuring station, and (2) the regional effect, dependent upon pollutant flows originating outside the local area. A large database is developed, making extensive use of GIS technology, to spatially relate such data as pollution measurements, meteorological factors, land‐use characteristics, census socioeconomic data, and major highway network characteristics. The results confirm the appropriateness of the well‐mixed cell framework, are in line with general knowledge regarding the determinants of ozone and carbon monoxide concentrations, and clarify the role of transportation, residential fuel use, economic activities, natural environments, and meteorological factors such as temperature and solar radiation. About SO percent of the variations in concentrations are explained by these models. Several areas of further research are outlined.  相似文献   
589.
试论拉丁美洲现代化步履维艰的文化根源   总被引:3,自引:0,他引:3  
天主教伦理是拉丁美洲文化体系的主要基础 ,这是西班牙和葡萄牙对美洲征服和殖民化过程中所留下的遗产。这套伦理观对拉美人的思想意识和行为方式产生了非常重要的影响 ,成为具有伊比利亚传统的拉丁美洲经济长期难以走出不发达的主要根源之一。拉美地区走出不发达的状态首先在于走出文化精神上的“不发达”。  相似文献   
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