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91.
92.
Igor V. Volvenko Andrey V. Gebruk Oleg N. Katugin Georgy M. Vinogradov Alexei M. Orlov 《Geographical Research》2023,61(4):503-511
Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach. 相似文献
93.
Sarah A. Bendall 《Gender & history》2023,35(1):42-67
This article examines the visual and material culture of sixteenth-century elite ceremonial armours and the paradoxes inherent in using images of women to decorate them between 1525 and 1550. It argues that foreign invading forces and their allies exploited or inverted traditional gender binaries associated with the classical and humanist iconography of the Italian Renaissance, particularly its female allegorical forms, to visually signify power relationships between combatants during the Italian Wars. Rather than simply embodying masculinity, elaborate ceremonial armours with images of women are revealing of both ideals of masculinity and femininity during times of war. These portrayals were part of wider conversations about gender and power, about the strength and weaknesses of women, and, ultimately, women's inferior status to men, which were utilised in allegorical forms to make claims to authority on these elite forms of male dress. 相似文献
94.
95.
In September 1968, one of the authors (P. Mayes), having been appointed Head of Mission by the British Ministry of Overseas Development to act as advisor to the Jamaica National Trust Commission, made recommendations which formed the basis for the establishment of the Port Royal Project. The Project is concerned with the excavation, conservation and presentation of 17th century Port Royal, which was founded in 1655 and destroyed by an earthquake in 1692 (see Fig. 1). For the purposes of archaeology the area was divided into three: the Archaeological-Historical Reserve, encompassing the protected underwater area and lands currently occupied by government facilities at the west end of Port Royal; the area in the centre of Port Royal which is protected archaeologically by modern housing and the area at the east end of Port Royal in which it was proposed that commercial expansion should be allowed on land held on lease from the Jamaican government. Work began early in 1969 in a section of this last area, which was threatened, at that time, by the construction of an hotel. This area was part of the shoal water section of sunken Port Royal (see below and Fig. 2). Since that date excavation headquarters and conservation laboratories have been established in the old naval hospital and the construction of a major museum, the first phase of the presentation programme, has begun. 相似文献
96.
V. MEJDAHL 《Archaeometry》1972,14(2):245-256
This article outlines the thermoluminescent dating technique employed at Risö. The intensity of beta and gamma radiation is determined by means of the TL phosphors CaSO4:Mn and CaSO4:Dy, and the determination of accumulated exposure is based on quartz and feldspar inclusions with a size of 0.3–0.5 mm. Results are presented of a dating programme comprising sherds, bricks, burned stones and burned clay (from kilns) from seventeen excavation sites. The age of the sites ranged from a.d. 1600 to 4000 b.c. 相似文献
97.
98.
In Search of Khayyam. By Ali Dashti (translated by L. P. Elwell‐Sutton). New York: Columbia University Press, 1972. 276pp. $11.00.
The Emergence of Modern Afghanistan: Politics of Reform and Modernization, 1880–1946. By Vartan Gregorian. Stanford: Stanford University Press, 1969. 398pp. $17.50. 相似文献
99.
A method is described for the identification of the origin of flint artefacts. The method is based on the variation in the trace element concentrations for different origins. The trace element concentrations were determined by non-destructive neutron activation analysis. The identification was obtained from a pattern recognition analysis. 相似文献
100.
RACIAL SEGREGATION: A COMMENT 总被引:1,自引:0,他引:1
Thomas A. Reiner 《Journal of regional science》1972,12(1):137-148