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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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David Jacoby 《Journal of Medieval History》1977,3(3):225-264
This case-study is the first attempt to examine a commercial outpost in the Crusader Levant within the context of the commercial and colonial expansion of its mother-city and in direct relation to its particular features. The Venetian quarter in Acre in the second half of the thirteenth century provided the physical setting for the exercise of authority by the state and a solid base for the expansion of its dominion. The Venetian administration there implemented the strict regulation of commerce and shipping enacted in Venice in this period, including several rules stemming from the particular needs of Acre. Various families of settlers from Venice, nobles as well as popolani, can be traced for several generations; the grant of Venetian status to natives of the Latin kingdom of Jerusalem, Latins oriental Christians, and Jews, enlarged the size of the Venetian population in Acre. The fate of the refugees who escaped from the city in 1291 is the last topic to be examined. 相似文献
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David Shankland 《Anthropology today》2012,28(2):3-4
This editorial anticipates the conference Anthropology in the World by reflecting upon the influence of anthropology, and its limits, arguing that it is only by knowing where these limits are that we can be sure where and how it can best be judged. It is too, a call for unity, suggesting that in seeking to influence the external world, anthropology should unite across its sub‐disciplines, and in doing so a mutually‐beneficial exchange of practice, ideas and methodology will emerge. 相似文献
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Jennifer G. Kahn John Sinton Peter R. Mills Steven P. Lundblad 《Journal of archaeological science》2013,40(2):1194-1202
We apply X-ray fluorescence (XRF) geochemical analysis to a collection of 'Opunohu Valley lithic artifacts from Mo'orea island to investigate the local scale of raw material procurement, adze production, use, and exchange within the Society Island archipelago. We use these data to document the distribution of non-local versus local volcanic artifacts in 'Opunohu Valley house sites, ritual sites, and specialized sites, as a means for establishing intra-site production and consumption patterns, and access to exotic, possibly superior, stone resources, and how these two themes correlate with site function or household wealth and status. Overall, 30% of the artifacts analyzed via WDXRF derive from non-local sources, notably two other islands in the archipelago outside of the political boundaries of Moorean chiefdoms. Our case study thus provides the first direct material evidence of intra-archipelago trade and exchange in the Society Islands. Intra-archipelago trade in adzes was certainly in place by as early as A.D. 1350, if not earlier, and continued up until the time of European contact. In addition, our analyses have identified a local adze production locale in the Afareaitu district of Mo'orea island. The patterns of local versus non-local adze production and exchange strongly suggest that dual interaction spheres were involved. The correlation between adzes and adze-related debris produced from off-island sources and sites with specialized use, which were often reserved for the social, ritual, and political elites in Ma'ohi society suggests that some of the exotic adzes derived from gift exchange between Mo'orea and ruling elites in Tahiti and the Leeward Islands. These adzes from afar would have solidified socio-political and ideological alliances between elites in the Windward and Leeward sectors of the archipelago. 相似文献
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