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971.
Markus Egli Luciano Gristina Guido L.B. Wiesenberg Jose María Martín Civantos Antonio Rotolo Agata Novara Dagmar Brandová Salvatore Raimondi 《Journal of archaeological science》2013
The aim of this work was to detect imprints on soil properties from former Islamic land use (9th to 11th century) using a multi-method, soil-chemical approach. Four soil profiles (with buried horizons) found in the vicinities of former Islamic settlements in Sicily were analysed for phosphorus (total, organic and inorganic), nitrogen (total, NO3− and NH4+), carbon compounds (δ13C, lipids, polycyclic aromatic hydrocarbons (PAH) and functional groups), physical and chemical C-fractions and the state of soil weathering. Two soil profiles contained ceramic sherds from the Islamic period. Inorganic nitrogen forms, phosphorous and the PAH content indicated strong impacts from traditional agriculture and/or burning. Radiocarbon dating of soil organic carbon (SOC) fractions from buried horizons showed that distinct changes must have occurred during the Islamic epoch. The isotopic composition of SOC indicated that land use was probably different in earlier times. C4 plant cultivation was expected but surprisingly lipid analyses did not confirm this. A high amount of aliphates and low C/N ratio indicated a good, long-term SOC stabilisation under the native conditions combined with Islamic land use. The irrigation of the soils probably increased the production of weakly-crystalline Fe forms that helped to stabilise SOC. 相似文献
972.
A. Simonneau E. Doyen E. Chapron L. Millet B. Vannière C. Di Giovanni N. Bossard K. Tachikawa E. Bard P. Albéric M. Desmet G. Roux P. Lajeunesse J.F. Berger F. Arnaud 《Journal of archaeological science》2013
A source-to-sink multi-proxy approach has been performed within Lake Paladru (492 m a.s.l., French Prealps) catchment and a 6-m long sediment sequence retrieved from the central lacustrine basin. The combination of minerogenic signal, specific organic markers of autochthonous and allochthonous supply and archaeological data allows the reconstruction of a continuous record of past human disturbances. Over the last 10,000 years, the lacustrine sedimentation was dominated by autochthonous carbonates and the watershed was mostly forest-covered. However, seven phases of higher accumulation rate, soil erosion, algal productivity and landscape disturbances have been identified and dated from 8400 to 7900, 6000 to 4800, 4500 to 3200, 2700 to 2050 cal BP as well as AD 350–850, AD 1250–1850 and after AD 1970. Before 5200 cal BP, soil erosion is interpreted as resulting from climatic deterioration phases towards cooler and wetter conditions. During the Mid-Late Holocene period, erosion fluxes and landscape disturbances are always associated with prehistorical and historical human activities and amplified by climatic oscillations. Such changes in human land-used led to increasing minerogenic supply and nutrients loading that affected lacustrine trophic levels, especially during the last 1600 years. In addition, organic and molecular markers document previously unknown human settlements around Lake Paladru during the Bronze and the Iron Ages. 相似文献
973.
974.
975.
A new genus and species of dasyurid is described on the basis of P3, M1–M3 and M2–3 collected from the middle Pliocene Chinchilla Local Fauna of south-eastern Queensland. Character analysis supports the placement of this new taxon within the dasyurid subfamily Dasyurinae. Derived dasyuromorphian features common to A. chinchillaensis and most dasyurines include: reduction of P3, reduction of stylar cusp B on M1; reduction of metaconids; approximation of stylar cusp B and the metacone on M1; alignment of the postmetacrista on M1 with the long axis of the maxilla and an oblique orientation of the hypocristids with respect to the long axis of the teeth. However in most instances, A. chinchillaensis is less specialised than other members of the subfamily for characters considered. One derived dental feature, reduction of the entoconid, may indicate a special relationship with ‘parantechinines’, Dasyuroides and/or Dasycercus. Additionally, the presence of this feature is suggestive of an open woodland/seasonal habitat. Autapomorphic P3 morphology compounds difficulties with the phylogenetic placement of this taxon. 相似文献
976.
Agustín G. Martinelli Sergio Bogan Federico L. Agnolin Luiz C. B. Ribeiro Camila L. Cavellani Mara L. F. Ferraz 《Alcheringa: An Australasian Journal of Paleontology》2013,37(1):105-113
Martinelli, A.G., Bogan, S., Agnolin, F.L., Ribeiro, L.C.B., Cavellani, C.L., Ferraz, M.L.F. & Teixeira, V.P.A., iFirst article. First fossil record of amiid fishes (Halecomorphi, Amiiformes, Amiidae) from the Late Cretaceous of Uberaba, Minas Gerais State, Brazil. Alcheringa, 1–9. ISSN 0311-5518. The first fossil amiid fishes (Halecomorphi, Amiiformes) from the Late Cretaceous Marília Formation (Bauru Group) at Uberaba County, Triângulo Mineiro region (Minas Gerais State, Brazil), are described. The material includes some partial maxillae, a dermopterotic, a cleithrum, several vertebral centra and teeth. Features such as the absence of a supramaxillary notch on the dorsal edge of the maxilla, a wide and deep pit on the maxilla for the articulation of the premaxilla, anterior portion of the maxilla with a sub-circular cross-section, teeth with acrodine cup with strong mesial and distal keels, among others, permit confident referral of the material to the Subfamily Vidalamiine (Amiidae), previously recognized in Lower Cretaceous strata of northeasthern Brazil. These specimens constitute the first Late Cretaceous record of this group in Brazil and one of the few in South America. Agustín G. Martinelli [agustín_martinelli@yahoo.com.ar], Centro de Pesquisas Paleontológicas Llewellyn Ivor Price, Complexo Cultural e Científico Peirópolis (CCCP/UFTM), BR-262, Km 784, Bairro Peirópolis, Uberaba, Minas Gerais, Brazil; Sergio Bogan [sergiobogan@yahoo.com.ar], Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, CEBBAD—Universidad Maimónides, Hidalgo 775 piso 7 (1405BDB), Buenos Aires, Argentina. Federico Agnolín* [fedeagnolin@yahoo.com.ar], Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo 470 (C1405BDB), Buenos Aires, Argentina. Luiz Carlos Borges Ribeiro [lcbrmg@terra.com.br], Camila Lourencini Cavellani [camila@patge.uftm.edu.br], Mara Lúcia da Fonseca Ferraz [mara@patge.uftm.edu.br] and Vicente de Paula Antunes Teixeira [vicente@patge.uftm.edu.br], Centro de Pesquisas Paleontológicas Llewellyn Ivor Price, Complexo Cultural e Científico Peirópolis (CCCP/UFTM), BR-262, Km 784, Bairro Peirópolis, Uberaba, Minas Gerais, Brazil. *Also affiliated with: Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, CEBBAD—Universidad Maimónides, Valentín Virasoro 732 (C1405BDB), Buenos Aires, Argentina. Received 15.4.2012; revised 11.6.2012; accepted 20.6.2012. 相似文献
977.
John B. Dunlop 《Eurasian Geography and Economics》2013,54(4):204-215
A prominent American Sovietologist examines a range of issues surrounding the involuntary migration of Russian populations from the non-Russian republics of the former USSR. Among the questions addressed are possible magnitudes of in-migration into Russia (with special attention paid to conditions in one of the major source regions, Central Asia), attitudes in Russia regarding appropriate policy with respect to treatment of co-nationals in the near abroad and whether their return to Russia would have a positive or negative impact, and conditions in areas of Russia that presently are absorbing the greatest numbers of migrants. The assertion that Russian policy should seek aggressively to prevent the out-migration of Russian populations in the near abroad is assessed critically. 1 table, 1 figure, 10 references. 相似文献
978.
The authors survey settlement in suburban zones of major cities as an important component of spatial and socioeconomic planning of settlement systems. “Inner” and “outer” suburban zones are identified—the former on the fringes of the built-up area of an agglomeration and the latter comprising exurban sites in oblasts adjoining the agglomeration. The substantial desire for and widespread use of second homes by city dwellers, particularly near sites of collective gardening, is viewed as a key component to be incorporated into future planning as a tool for regulating the influx of urbanites into the countryside (translated by H. L. Haslett, Leamington Spa, UK). 相似文献
979.
Denis J. B. Shaw 《Eurasian Geography and Economics》2013,54(3):207-228
This paper compares and contrasts Russian frontier experiences on the northern and southern parts of the European plain during the Romanov era (1613-1917). Both were “open” frontiers, in Turner's sense of a frontier as the “hither edge of free land,” but their environments and the settlement processes which affected them were very different. It is suggested that the character of a frontier society is decisively influenced by the process whereby settlers must adapt to their new environment, the features which attract them to that environment, and the character of the pre-existing inhabitants. The northern frontier formed part of what Meinig has called a “boreal riverine empire” with a harsh environment, to which paradoxically the Russians found it relatively easy to adapt, the great attraction of fur-bearing animals and reasonably benign relations with native peoples. By contrast, the southern frontier was a “frontier of exclusion,” following Lattimore's phrase, with hostile indigenes, a natural environment demanding special methods of adaptation, but with many more attractions than the north. Such contrasts gave rise to considerable differences in the settlement process, in the character of land allocation and in the type of society evolving subsequently, with long-term consequences for emerging human landscapes. 相似文献
980.
During a geo‐sequestration process, CO2 injection causes an increase in reservoir pore pressure, which in turn decreases the reservoir net effective stress. Changes in effective stress can change all the reservoir and cap‐rock properties including residual saturations. This article presents the results of an experimental work carried out to understand the potential change in the volumes of residually trapped CO2, while the porous medium tested underwent change in the net effective stress under in‐situ reservoir conditions of pore pressure and temperature. The experimental results obtained show that an initial 1725 psi (11.9 MPa) decrease in the net effective pressure caused 1.4% reduction in the volumes of residually trapped CO2, while another 1500 psi (10.3 MPa) reduction caused a further 3.2% drop in the residual saturation of CO2. 相似文献