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331.
David Alexander 《The Professional geographer》2000,52(3):553-566
Pasta is as much an institution as a food in Italy, where it has made a significant contribution to national culture. Its historical geography is one of strong regional variations based on climate, social factors, and diffusion patterns. These are considered herein; a taxonomy of pasta types is presented and illustrated in a series of maps that show regional variations. The classification scheme divides pasta into eight classes based on morphology and, where appropriate, filling. These include the spaghetti and tubular families, pasta shells, ribbon forms, short pasta, very small or “micropasta” types, the ravioli family of filled pasta, and the dumpling family, which includes gnocchi. Three patterns of diffusion of pasta types are identified: by sea, usually from the Mezzogiorno and Sicily, locally through adjacent regions, and outwards from the main centers of adoption. Many dry pasta forms are native to the south and center of Italy, while filled pasta of the ravioli family predominates north of the Apennines. Changes in the geography of pasta are reviewed and analyzed in terms of the modern duality of culture and commercialism. 相似文献
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333.
Hydraulic pathways in the crystalline rock of the KTB 总被引:1,自引:0,他引:1
334.
青藏高原东缘活动构造 总被引:74,自引:0,他引:74
青藏高原东缘由岷山断块和龙门山构造带构成。以活动构造地貌学为主线,在解析该地区主干断裂晚第四纪以来活动的地质地貌表现的基础上,对一批断裂运动学和史前强震活动的定量数据进行分析研究,结果表明:在岷山断块中,虎牙断裂的平均左旋滑动速率为1.4 mm/a,垂直滑动速率为0.3 mm/a。岷江断裂的平均垂直滑动速率介于0.37 mm/a~0.53 mm/a之间,左旋位错量与垂直位错量大致相当;在龙门山构造带中,茂汶-汶川断裂、北川-映秀断裂和彭县-灌县断裂的平均垂直滑动速率均在1 mm/a左右,且几条主干断裂的右旋位错量与垂直位错量相当。结合震源机制解结果和GPS测量资料,建立晚新生代以来青藏高原东缘向南东方向逸出的构造变形模式。 相似文献
335.
Currently used and newly proposed calculation techniques for the heightof the stable boundary layer (SBL), including the bulk-Richardson-numbermethod, diagnostic equations for the equilibrium SBL height, and a relaxation-typeprognostic equation, are discussed from the point of view of their physical basis andrelevance to experimental data. Among diagnostic equations, the best fit to data exhibits an advanced Ekman-layer height model derived recently with due regard to the role of the free-flow stability. Its extension to non-steady regimes provides a prognostic equation recommended for use in practical applications. 相似文献
336.
RESEARCH ON THE RELATIONSHIP BETWEEN FRACTAL FACTORS AND TECTONIC ACTIVITY——A CASE STUDY OF SOUTHWESTERN YUNNAN BLOCK
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Geomorphology could record long-term accumulation of tectonic movement and quantify it by relevant parameters.But because the influences of other factors such as climate and lithology,how to use the relevant parameters to reveal the relationship between geomorphology and tectonics is a research hot spot.In this paper,we utilize the variogram method and the cellular fractal model to estimate parameters such as the fractal dimension (D) and ordinate intercept (γ) from the SRTM3 DEM using a moving window operation.We compare the distribution characteristics of the parameters in different climate and lithology.The results indicate that the correlation between the parameters and lithology or climate is very poor.The fractal dimension (D) reveals a very good correlation with tectonics,which is low in tectonically inactive areas and high in active areas.It implies that fractal dimension (D) may be a new method for research of regional tectonic movement. 相似文献
337.
Yuri D. Zakharov Yasunari Shiget Kazushige Tanabe Yasuhiro I Olga P. Smyshlyaev Ekaterina A. Sokolov Alexer M. Popov Tatiana A. Velivetskay Tamara B. Afanasyeva 《《地质学报》英文版》2007,81(6):1049-1069
Paleoclimatic settings have been reconstructed for the Campanian using original oxygen-isotopic analyses of well-preserved molluskan and foraminifera shells from Russian Far East, Hokkaido, USA, Belgium and some DSDP holes (95, 98, 102, 390A, and 392A) in North Atlantic. Early Early Campanian climatic optimum has been recognized from data on high bottom shelf water paleotemperatures in middle latitudes of both the western circum-Pacific (to 24.2°C) and the eastern circum-Pacific (to 26.4°C) areas and high bottom shallow water paleotemperatures in high latitudes of the Koryak Upland (22.4–25.5°C), which agrees with the data on the Campanian Barykovskaya flora in high latitudes (Golovneva and Herman, 1998) and Jonker flora and its equivalents in middle latitudes. Judging from the data on comparatively high bottom shallow water paleotemperature values in high latitudes, South Alaska (19.4°C) and the Koryak Upland (22.4–25.5°C), we also expect Latest Campanian temperature maximum, which has not been confirmed, however, for low and middle latitudes by neither of isotopic nor paleobotanic data now. Main climatic tendency during the Campanian (with the exception of Latest Campanian) has been learned from isotopic composition of Campanian aragonitic ammonoid shells from the Hokkaido-South Sakhalin (Krilyon) marine basin. In contrary to Huber’s et al. (2002) assumption, we expect warm greenhouse conditions during the most part of the Campanian. 相似文献
338.
Anthropogenic nitrogen deposition induces rapid ecological changes in alpine lakes of the Colorado Front Range (USA) 总被引:7,自引:3,他引:7
Recent sediments from two alpine lakes (> 3300 m asl) in the Colorado Front Range (USA) register marked and near-synchronous changes that are believed to represent ecological responses to enhanced atmospheric deposition of fixed nitrogen from anthropogenic sources. Directional shifts in sediment proxies include greater representations of mesotrophic diatoms and increasingly depleted 15N values. These trends are particularly pronounced since ~ 1950, and appear to chronicle lake responses to excess N derived from agricultural and industrial sources to the east. The rate and magnitude of recent ecological changes far exceed the context of natural variability, as inferred from comparative analyses of a long core capturingthe entire 14,000-year postglacial history of one of the lakes. Nitrogen deposition to these seemingly pristine natural areas has resulted in subtle but detectable limnological changes that likely represent the beginning of a stronger response to nitrogen enrichment. 相似文献
339.
340.
A system of equations has been derived for the modes of free oscillation of the magnetosphere when it is regarded as an adiabatic magnetic dipole trap filled with cold inhomogeneous plasma. The limiting case of infinite longitudinal conductivity corresponding to the assumption that the electric field is orthogonal to the geomagnetic field has been studied. The boundary at the ionosphere is supposed to be perfectly conducting.The eigenmode spectrum has been found to have discrete and continuous components. The eigenmodes of the discrete component correspond to quasi-magnetosonic modes and the eigenmodes of the continuous component to quasi-Alfvén modes.Assuming the magnetosphere to be axisymmetric, a general expression in the form of a Frobenius series has been derived for quasi-Alfvén oscillations of magnetic shells near resonant magnetic surfaces. 相似文献