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Evidence from several disciplines supports the proposition that following the Wisconsinan and an initial but brief moist phase of the Holocene, there was a gradual drying trend in the mid-continent Prairie Peninsula that peaked about 7000 years ago, a pattern that was not reversed until about 4000 years ago. Except for minor perturbations, conditions during the past four millennia have essentially been similar to those of the present. Studies in palynology and geomorphology have shown that the climatic regimes of the early/mid Post-glacial had a marked influence on both the biota and landscape erosional patterns, especially along the margins of the Prairie Peninsula. Measurable changes in the landscape and attendant biota show a time-transgressive pattern of drought related phenomena recorded palaeo-ecologically from west to east.Few studies of archaeological sites in the Prairie Peninsula have examined the evidence in and around the sites themselves for data reflecting local environmental dynamics. In fact, earlier models proposed for explaining the evolution of food-procuring systems in eastern North America virtually ignored potential changes in the natural environment. This paper examines data from two archaeological sites along the prairie-forest border in Missouri that contain long cultural sequences. Evidence is presented that pronounced changes in the natural environment occurred and that these biophysical variables are indeed critical for understanding the evolution of food-procuring societies in the American Midwest. 相似文献
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Keith Manchester 《Journal of archaeological science》1981,8(2):205-209
A male skeleton of 7th century date from the Anglo-Saxon cemetery at Eccles, Kent, is described. Certain skeletal changes associated with leprosy are manifest. The disease is discussed in its palaeopathological context and this case in relation to the few other cases of the disease hitherto diagnosed in Great Britain. 相似文献
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Keith D Lilley 《Journal of Historical Geography》2000,26(4):517
By playing on the Classical belief that urbanity is a sign of civility, urbanism has often been used by Europeans to characterize the «other» as uncivilized. In the twelfth century, contemporary chroniclers in England made much use of the myth that Wales and Ireland were unurbanized and therefore uncivilized. This conviction provided, in their view, a justification for colonizing lands in Wales and Ireland, at the western edge of the Anglo-Norman kingdom. Throughout the twelfth and thirteenth centuries, the process of this colonization was intimately linked with urbanization. This paper examines the spatial dimensions of this process and proposes two views of how urbanization facilitated colonization. First, English domination was extended geographically by the use of particular Anglo-Norman urban laws, and by the foundation of chartered towns. These laws spread English legal practices into Wales and Ireland, reinforcing the myth that these areas lacked urbanity before colonization, whilst at the same time placing them under the watchful eye of Anglo-Norman lordship. Secondly, in the creation of chartered «new» towns, Anglo-Norman lords used exclusionary devices to structure the internal spaces of towns, separating English townspeople from Welsh and Irish and in the process marking them as «outsiders» in a «colonial» society. 相似文献
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Trigger levels for fine suspended sediment (FSS) load in streams are required to identify rainfall-runoff events that have significantly elevated FSS loads, compared with expected background loads, as a result of catchment disturbance. Stream FSS load data collected in the mine-impacted Magela Creek catchment in the wet-dry tropics were used to derive water quality management trigger levels for two approaches – a Before-After-Control-Impact Paired difference design (BACIP) and a regression relationship between observed FSS load and corresponding event discharge characteristics. The results indicate that both the BACIP and regression relationship approaches behave similarly, with similar FSS load events elevated above trigger levels. Notwithstanding this, it is recommended that in order to reliably assess the location and magnitude of a catchment disturbance on FSS load, a combination of BACIP and regression relationship approaches must be adopted. In this study, an event with a FSS load above trigger levels associated with both BACIP and the regression relationship fitted for the downstream site is considered to be significantly elevated as a result of a disturbance within the mine-impacted region. While this technique cannot conclusively determine whether the cause of the disturbance is mine-related or natural (such as fire or bank erosion), it is an efficient statistical method of identifying events that warrant further investigation and management action, if required. 相似文献
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