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1.
Emily Dix, the Coal Measures palaeobotanist, was born on 21 May 1904. She was one of four daughters in a family of five children brought up in Penclawdd – a South Welsh cockling port then surrounded by coal and copper smelting industries near Swansea. Emily was a bright and gregarious girl, gaining at the age of 18 the Central Welsh Board Higher Certificate in History, Botany and Geography with distinctions in history and botany. Her success was an indication of what was to come.  相似文献   
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Continental break-up: The East African perspective   总被引:1,自引:0,他引:1  
Cynthia Ebinger discusses the evolution of continental rifts through the example of the East African Rift system, in the Bullerwell Lecture, given at the European Union of Geosciences meeting in Nice, April 2004.  相似文献   
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Abstract

Multi‐temporal ERS‐1 SAR data acquired over a large agricultural region in West Bengal was used to classify kharif crops like rice, jute and sugarcane. Rice crop grown under lowland management practice showed a temporal characteristic. The dynamic range of backscatter was highest for this crop in temporal SAR data. This was used to classify rice using temporal SAR data. Such temporal character was not observed for the other study crops, which may be due to the difference in cultivation practice and crop calendar. Significant increase in backscatter from the ploughed fields was used to derive information on onset and duration of land preparations. Synergistic use of optical remote sensing data and SAR data increased the separability of rice crop from homesteads and permanent vegetation classes.  相似文献   
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Cynthia 《地图》2006,(2):24-25
风花雪月诗酒花,柴米油盐酱醋茶,无论是自诩为文人骚客还是自嘲为下里巴人,生活的方式也许不一样,自由的精神却是一致的,选择的权利也是平等的,于是,面对同样的物什,有人狂喜,有人远离,有人理智地分析,有人感性地沉迷。  相似文献   
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Commercial fishers report finding their lobster traps often great distances from their original location following major hurricanes. But traps also move during lesser wind events, such as during winter cold fronts. To assess trap impact on coral communities following winter storms, lobster traps were placed in hardbottom and reef habitats commonly used by commercial fishers in the Florida Keys, United States. Trap movement, percentage benthic faunal cover, and benthic faunal damage were assessed after 26 wind events occuring over three winters. Traps moved when storms with sustained winds greater than 15 knots (27.8 km/h) persisted for more than 2 days. Winter storms above this threshold moved buoyed traps a mean (±SE) distance of 3.63 ± 0.62 m, 3.21 ± 0.36 m, and 0.73 ± 0.15 m per trap and affected a mean area of 4.66 ± 0.76 m2, 2.88 ± 0.29 m2, and 1.06 ± 0.17 m2, per trap at 4‐m, 8‐m, and 12‐m depths, respectively. Unbuoyed traps, simulating derelict traps, moved a mean distance of 0.43 ± 0.08 m and 0.44 ± 0.02 m, and affected a mean area of 0.77 ± 0.06 m2 and 0.90 ± 0.08 m2 per trap at 4‐m and 8‐m depths, respectively. Injuries caused by trap movement included scraped, fragmented, and dislodged sessile fauna, resulting in significant damage to stony coral, octocoral, and sponges. Overall, sessile fauna cover along the trap movement path was reduced from 45% to 31%, 51% to 41%, and 41% to 35% at the 4‐m, 8‐m, and 12‐m sites, respectively. Because of the large numbers of traps deployed and reported lost each season, damage to sessile fauna and loss of benthic faunal cover caused by traps needs to be considered to effectively protect coral reefs and manage essential fishery habitat in the future.  相似文献   
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This paper examines the relationship between local institutions and adaptation to climate variability in four semi-arid villages in India. Based on a qualitative survey, it draws attention to the constraints that farming households face, the role of institutions, and the implications for their capacities to adapt. Using an institutional framework, the study examines the role of local institutions in facilitating community adaptation to perceived climate variability. It was found that at the institutional and community level farmers rely on government schemes that provide social safety nets and the private sector such as moneylenders as sources of adaptation options regarding access to credit. Serious constraints emerged, however, in terms of adaptation to what may be a more challenging future. These constraints were further explored by means of grounded theory. The lack of collective feeling and action has hindered bargaining for better market prices and the development of alternate livelihood options. The need for better financial inclusion and access to more formal systems of finance is necessary to increase the overall adaptive capacity of households. During crisis situations or climatic shocks, the absence of these systems means the sale of household assets and resources especially among small and landless groups of farmers. Overall, rural households perceive that public, civic, and private institutions play a significant role in shielding them against the adverse effects of climate variability. The perceived importance of different institutions is, however, different across different categories of farmers, women, and labourers.  相似文献   
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The presence of decapod crustaceans in the Pliocene and Pleistocene (MIS 5e) fossil record of Santa Maria Island (Azores Archipelago) is herein reviewed. Our study raises the number of fossil decapods from this island from one species to 10 taxa (three for the Pliocene and seven for the Last Interglacial). Four of these 10 taxa are reported for the first time in the fossil record, worldwide. A new species of a mud shrimp is also described (Upogebia azorensis n. sp.). Our study suggests that the Plio–Pleistocene decapod assemblages of the Azores did not differ significantly from modern ones, being dominated by species that are today widespread across the Webbnesia ecoregion, the Mediterranean Sea, and the eastern Atlantic shores, including the Azores. As far as can be judged from the limited fossil record, apparently no tropical crab species with a Cabo Verdean/Senegalese provenance reached the Azores during windows of opportunity associated with Glacial Termination 2 or with the initial setting of the Last Interglacial period. This contribution increases the total number of marine taxa reported for the Pliocene and Pleistocene outcrops of Santa Maria Island to 218 and 155, respectively, highlighting the scientific relevance of its palaeontological heritage.  相似文献   
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