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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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