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The River Murray is a highly regulated, low gradient stream. Prior to barrage construction near the Murray Mouth saline water was present sporadically far upstream. Barrage completion by 1940 has had geo-morphic and ecological impacts. Estuarine Lakes Albert and Alexandrina became permanent freshwater bodies with elevated water levels. Exposed lake margins have eroded by up to 10 m yr', whereas along sheltered shorelines, sedimentation has accompanied reed growth. Upstream weirs have inhibited coarse sediment from reaching the lakes. In the Goolwa Channel, sedimentation changed from bioclas-tic sands to muds, accumulating at up to 4.5 mm yr' over the past 50 years. Regulation has also transformed a migrating flood tidal delta at the Murray Mouth into a permanently vegetated island. 相似文献
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James M. Edmonson 《Journal of the history of the neurosciences》2019,28(2):277-284
ABSTRACTMedical museums and collections care for important artifacts relating to the history of the neurosciences across the United States, the United Kingdom, and Europe. This essay highlights the collections and galleries of greatest interest and worth a visit. It also provides a list of online directories of medical museums and bibliography of related publications. 相似文献
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‘They call ’im Crowie’: an investigation of the Aboriginal significance attributed to a wrecked River Murray barge in South Australia
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Amy Roberts Wendy van Duivenvoorde Michael Morrison Ian Moffat Heather Burke Jarrad Kowlessar John Naumann 《International Journal of Nautical Archaeology》2017,46(1):132-148
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位于长江入海口的“长江口二号”清代沉船是中国目前发现的保存最为完整的古代木制沉船之一,已于2022年11月完成整体打捞。在进行水下考古调查时,沉船出水的部分青花瓷出现的病害现象引起了考古工作者的关注,特别是裂纹中黑色污染物及表面铁锈状污染物对文物的外观产生了很大影响。本工作选取了三件具有典型被污染特征的青花瓷标本作为代表,使用能量色散X射线荧光分析(EDXRF)、光学显微镜(OM)、X射线衍射分析(XRD)、拉曼光谱分析(Raman)和扫描电子显微镜-能谱分析(SEM-EDS)等方法,对污染物进行了研究,探讨了其形成原因以及环境的影响作用,并对其潜在危害进行了分析。研究表明,污染物主要以方解石、菱铁矿等碳酸盐以及铁的氧化物、氢氧化物和硫化物为主。长期处于河口淤泥中的还原性环境是导致菱铁矿和亚稳的铁硫化物形成的原因,船体中铁质构件腐蚀对局部环境的污染是重要的影响因素,这也反映出被污染的青花瓷所处位置和环境的特殊性。出水的部分青花瓷釉中裂纹的形态表明其形成是由物理撞击造成,而釉中硅灰石晶体的选择性腐蚀会导致腐蚀坑的形成,裂纹和腐蚀坑均为外部污染物进入釉层内部提供了通道,导致瓷器劣化。出水后... 相似文献
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There is a widespread perception amongst the community of Ingham and surrounding areas that the Herbert River in tropical Queensland has aggraded since the time of European settlement. Yet this perception is not supported by such evidence as historical accounts of the river and river trade, changes at the Ingham gauging station since 1940 and comparison of channel cross-sections surveyed since 1968. No reason has been identified for this divergence, but experience elsewhere teaches us that ignoring local perception is likely to result in an incomplete understanding of environmental issues. Unless the challenge of reconciling popular perception and deductive interpretation of the evidence is met, the potential for conflict will remain. Community proposals for strategies will struggle for support from the ‘rationalists’ and the community will oppose ‘rational’ strategies if they are not seen to be addressing the ‘real’ problems. 相似文献
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杨伟兵 《中国历史地理论丛》2001,16(1):16-22
重庆至湖北宜昌段川江水系的分布与变迁对长江上游航运、沿岸聚落环境等社会经济均有一定的影响,也是现今三峡库区建设需要认真考察的课题。文章着重对该区域内主要水系的历史名称、河道变化进行考证与辨识,并相应地分析部分河流在航运、灾害方面发生变化的自然因素和人文因素。 相似文献
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泉州湾宋代海船的保护是我国上海洋出水大型古沉船保护的先例,具有自己的特点。泉州宋船使用先复原再经4年多缓慢自然阴干脱水的方式成功地保存了船体,而早期保护未脱盐及复原时使用大量铁钉给后期保存带来了严重破坏性后果。目前,船体经过40年的保护,整体结构基本稳定,但由于难以彻底解决早期保护遗留的问题,在开放式的保存条件下,其长期稳定保存难以实现。因此,综合现状与保护分析,从控制船体保存环境入手,尽可能抑制或延缓各种物理、化学与生物作用,是当前阻止船木继续劣变,延长船体寿命的最有效可行的途径。 相似文献
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Francisco Alves Paulo Rodrigues Miguel Aleluia Ricardo Rodrigo Catarina Garcia Eric Rieth Eduardo Riccardi 《International Journal of Nautical Archaeology》2001,30(1):12-36
The remains of a coasting vessel were found in a lagoon close to the coast. Four radiocarbon determinations provided a date in the mid-15th century and it has been the subject of several seasons of excavation of CNANS. The excavation strategy is described, as are its surviving constructional details which are analysed with reference to early sources for Portuguese naval architecture. This coaster has constructional features found in ocean-going ships of the Iberian-Atlantic tradition. Its cargo of pottery is one of the most extensive and closely dated from the Age of Discovery and includes 18 forms. 相似文献
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Regional development in a resource production system: long distance commuting,population growth,and wealth redistribution in the Western Australia Goldfields
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Kirsten Martinus 《Geographical Research》2016,54(4):420-432
Resource towns often exist on a knife‐edge, largely depending upon global demand for their resource/s and, at the same time, playing a critical role in the development of a nation. The transition from single resource towns to diversified economies has been modelled on several occasions, but their application to other resource locales is difficult given the unique interplay of geographic, political, social, and economic factors. Nonetheless, Innis' Canadian staples theory may explain the political motivations of resource extraction and exportation, not least in relation to the Western Australia Goldfields. This paper seeks to explore the theory's potential in this context by examining the implications of high labour mobility. It employs a two‐step process using, first, a social network analysis to map the entire Australian labour commuting network and, second, a regression analysis of commuting, regional wealth, and population size against population change. While the Goldfields historically grew in line with processes described by Innis' theory, contemporary high labour mobility has created a variegated landscape of different development dynamics and trajectories. This finding carries implications for network patterns of residence and work. Labour acts to extend the distribution of wealth by sending incomes to the metropolitan core and to amenity‐rich regional towns across the State and nation. In such light, regional development scholars must view the resource town in its broader urban system of distinct but interlocked, and sometimes overlapping, activity nodes. 相似文献
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The Akko 1 shipwreck was discovered inside the harbour of the old walled city of Akko (Acre, St. Jean d'Acre, Akka), Israel. The ship's hull was built mainly of oak, with closely-set framing timbers that created a solid side. The shipwreck was apparently a result of the naval bombardment of the town in 1840. 相似文献
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《Journal of Field Archaeology》2013,38(2):134-150
AbstractWell preserved ancient shipwrecks are rare in the archaeological record, but when discovered, they can provide valuable information on a wide range of research issues if analyzed and documented properly. In this paper we discuss the significance, potential, and constraints of mapping methods applied during the underwater excavation of shipwreck sites with special emphasis on stratigraphy, documentation of finds, and reconstruction of site formation processes. As a case study, we present the digital photogrammetry and computer vision software programs used in the excavation of the 4th-century b.c. shipwreck at Mazotos, Cyprus. Our goal is to develop a targeted documentation and mapping method of ongoing shipwreck excavations so that others can address complex research questions concerning this unique discipline of archaeology. 相似文献
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Mick Hillman 《Geographical Research》2005,43(2):152-161
Dealing with differing and sometimes conflicting criteria for priority‐setting is an essential part of sustainable natural resource management. However, all too often, these ethical and political considerations are neglected within a planning regime based upon apparently ‘objective’ biophysical assessment techniques. Input into associated decision‐making processes is also frequently restricted to a narrow range of ‘stakes’ based upon historical and geographic circumstances. This paper reports on the findings of interviews and discussion groups in the Hunter Valley, New South Wales, which aimed to canvass the diversity of perceptions of distributive and procedural justice in river rehabilitation. A range of biophysical and social criteria for setting priorities in rehabilitation work was identified. Participants also had differing ideas on the composition of decision‐making bodies and on decision‐making processes. The key implications of these findings are that sustainable river management policy needs to openly address differing conceptions of justice and that rehabilitation practice should be holistic, transdisciplinary and concerned with both outcome and process. 相似文献
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《Journal of archaeological science》2005,32(2):167-181
We analyse archaeobotanical remains from three excavated rockshelter sites, Jinmium, Granilpi and Punipunil, in the Keep River region, northwestern Australia. The record is dominated by burnt fragmented seed remains from the fruit trees Persoonia falcata and Buchanania obovata, consistent with ethnographic records of whole fruits being pounded into pastes and cakes at the beginning of the summer wet season. Surface seed samples of non-cultural origin are mostly whole and unburnt, and contain higher proportions of grass seeds. Sustained processing of fruit seeds is first visible in the archaeological record about 3500 years ago. Spatial and temporal variation in its intensity is evident since that time until it declines following European colonisation. The decline does not represent total site abandonment, but a reorientation of activities following the ecological and social changes that came with pastoralism. The former included the local decline of P. falcata with more intense fire regimes. 相似文献
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E.D. Mentovich D.S. Schreiber Y. Goren Y. Kahanov H. Goren D. Cvikel D. Ashkenazi 《Journal of archaeological science》2010
The Akko 1 shipwreck constitutes the remains of a small Mediterranean naval vessel, discovered in Akko harbour, Israel, and excavated over three seasons between 2006 and 2008. Among the finds at the shipwreck site were eleven cannonballs. Two of them, a 9-pdr and a 24-pdr, were retrieved and studied using metallurgical and petrographic methods. The examination of the cast-iron was performed with optical microscopy, SEM–EDS, XRF and microhardness tests. The remains of the casting sand from within the voids in both cannonballs were studied by petrography. Combined with the archaeological evidence and the historical background, the metallurgical and petrographic testing may suggest that Akko 1 was a warship or an auxiliary naval vessel of similar size to, or slightly smaller than, sixth rate, and was in Akko harbour circa 1840. 相似文献