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1.
The environmental impact of smelter gases of the nickel-copper complexes of Sudbury, Ont., and Monchegorsk, in the Soviet Union's Kola Peninsula, is compared. Despite the larger volume of production and of emissions from the Sudbury smelters, exceeding those of Monchegorsk by one order of magnitude, a relatively smaller area around the Sudbury smelter is affected by pollutants. The greater vulnerability of the biotic environment around Monchegorsk is related to the fact that the Soviet smelter complex lies in the northern tayga, with smaller biomass and biological productivity, while the Sudbury complex is situated in a richer forest region of mixed broadleaf and needle species, corresponding to the southern tayga in the Soviet Union.  相似文献   

2.
A development strategy is proposed for the Nonchernozem zone of the European RSFSR, which is now the object of a major program of rural modernization (see S.G., March, April 1975). The principal factors affecting future strategy are geographical situation and physical setting, resource potential, level of economic development and settlement, availability of skilled labor and technical progress. The proposed strategy calls for focusing northern development on resource exploitation, fostering manufacturing development in the central oblasts outside the major industrial nodes, where industrial expansion should be restricted, and limiting industrial construction in the southern grain-growing oblasts to avoid diverting valuable agricultural land to nonfarm uses. The Nonchernozem zone will continue to be the nation's research and development center and aim at economic growth through intensive methods in view of a labor shortage.  相似文献   

3.
A continuing critique of the Soviet school of anthropogenic landscape science (see Soviet Geography, October 1974) questions whether man is, in fact, capable of creating “new” landscapes or his intervention in the natural environment simply tends to “modify” existing natural landscapes. The author rejects the view that significant modification of anyone of the components of landscape (including flora and fauna) is sufficient to produce an anthropogenic landscape or that a cutover forest area or a cattle trail, for example, represents a newly created landscape. A genuine modification of landscape requires an alteration of the basic structure of landscape, and this can be achieved only through modification of primary landscape components, such as the geomorphic foundation and climate. These are precisely the components that are less susceptible to human intervention than secondary components like plant and animal communities. Another criterion of basic landscape modification is stability; most anthropogenic landscapes turn out to be unstable when abandoned. Man achieves the most stable results in landscape modification by acting in concert with natural dynamic tendencies in the landscape.  相似文献   

4.
Eastern Sicily (southern Italy) is characterised by the presence of many natural gas emissions (mofettes, mud volcanoes). These gases are mostly carbon dioxide and methane, with minor amounts of helium, hydrogen, carbon monoxide and hydrocarbons. In this study, the extent and orientation of soil gas anomalies (He and CO2) were investigated on a wide area (approximately 110 km2) located just SW of Mt. Etna. From a structural point of view, this area lays on a typical foredeep–foreland system that marks the boundary between the southern part of the Eurasian plate and the northern part of the African plate in the central Mediterranean. No tectonic structure was revealed in this area by surface geological surveys. Very high soil emissions were found, and their spatial pattern reveals the existence of some active faults all directed about N50°E. This direction coincides with that of two major fault systems that cut eastern Sicily and are evident, respectively, NE and SW of the study area. Soil gas data suggest that these fault systems are the expression of a single continuous structural line which is probably responsible for the past and present magma uprise in eastern Sicily. Isotopic values of carbon of CO2 suggest a minor contribution of organic carbon. Moreover, in the highest degassing sites the isotopic values of He found in association with CO2 (He abundance = 11–70 p.p.m.; R/Ra between 6.0 and 6.2) suggest that both gases are mantle derived. The extent of the areas affected by high gas emissions and the amounts of deep CO2 emitted in the investigated area (several hundred tonnes per day) may provide additional supporting evidence of a mantle upwelling taking place beneath this region.  相似文献   

5.
The graphical and linguistic interpretation of the first six Etruscan numerals has long been confronted with the ambiguous assignment of the words huth and sa to either 4 or 6. Here, we show how the systematic combinatorial analysis of the numerals appearing on ancient southern Etrurian dice dated from the eighth to the third centuries bc , together with the careful comparison of the results with the only two existing dice carrying the alphabetical translations of the numerals conserved at the Bibliothèque Nationale de France, Paris, finally allows unambiguous mathematical resolution of the linguistic riddle, allowing the firm attribution of the numeral 6 to the graphical value huth and 4 to sa. Combinatorial analysis of the numerals distribution on the six faces of the die shows that only two of the 15 possible numerical combinations were actually in use in southern Etruria, and that during the fifth century bc there was a marked shift from the typical (1–2, 3–4, 5–6) combination used in the early seventh‐ to fifth‐century bc dice to the (1–6, 2–5, 3–4) combination used at later times and still largely adopted today. The largest body of archaeometric data on dice specimens from Etruria is presented, based on macroscopic examination, X‐ray diffraction, DRIFT spectroscopy and density measurements.  相似文献   

6.
The various types of natural landscapes of West Siberia are analyzed in terms of the environmental impacts of the more common forms of human activity. These are natural gas extraction and reindeer herding in the northern tundra; oil extraction and logging in the middle taiga, and agriculture as well as manufacturing in the southern wooded steppe and steppe. The impacts of human activity on specific natural processes (cryogenesis, bog formation, salinization) are discussed. The territory of West Siberia is broken down into three types of environmental impact regions: regions of significant impacts (from oil and gas extraction and agriculture); regions of moderate impacts (from logging and reindeer herding); and a region in which natural landscape structures have remained virtually unaffected by human activity.  相似文献   

7.
Micromammalian bone assemblages from modern pellets of the strigiform Bubo virginianus magellanicus, from the upper Atuel River (southern Mendoza, Argentina), were taphonomically analysed. The results allow us to place B. v. magellanicus in the category of intermediate modification (Category 2). This sample has also been compared with results from other members of this genus, in order to classify B. v. magellanicus as a taphonomic agent. The participation of the Bubo species in archaeological accumulations has been documented, but in Argentina, the role of B. v. magellanicus has been reported up to the present. It is partly because of the sequence of one archaeological site in the south of Mendoza Province called Laguna El Sosneado‐3 (LS‐3). However, considering the absence of a current taphonomic model of this owl, this participation was mentioned as a hypothesis. In the current investigation, archaeological and modern samples have been compared. The results indicate that the skeletal element assemblages recovered from LS‐3 were accumulated by strigiform birds. Taphonomical evidence of light modifications on units I and IV indicates that Tyto alba (Category 1) was probably the main species involved in these units, whereas the taphonomical evidence on skeletal element assemblages recovered from units II and III suggests the action of a strigiform with a major category of modification such as B. v. magellanicus. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

8.
The distribution of foraminiferids within Aptian-Albian marine deposits of the Laura, Carpentaria, Eromanga, and Surat Basins in Queensland is described. The foraminiferal distribution patterns are largely a reflection of environmental differences which existed within the basins. Among the benthonic foraminiferids, two major faunal associations are recognized: the Ammobaculites association reflecting hyposaline, cool, shallow water conditions; and the Marssonella association indicating normal marine, open continental shelf environments. As the faunal content of these associations is markedly different, separate time-stratigraphic zonations are proposed: the Ammobaculites association is divided into the Textularia cushmani zone (early Aptian), T. cushmani-Bigenerina pitmani zone (late Aptian), B. pitmani zone (late Aptian), B. pitmani-Riyadhella crespinae zone (early Albian), and R. crespinae zone (early-late Albian); the Marssonella association contains the Anomalinoides intermedia zone (early-middle Albian in Queensland), and the A. cenomanica zone (late Albian in Queensland). Planktonic foraminiferids, which occur with both benthonic associations, are used to correlate the benthonic zonal schemes, and are themselves zoned separately: Hedbergella planispira zone (early-middle Albian), H. infracretacea zone (middle-early late Albian), and the H. delrioensis zone (late Albian). International stage correlations are based on certain foraminiferids and associated ammonites.

The distribution of foraminiferids in Queensland during the late Early Cretaceous suggests that 1, climate exerted a uniform influence over the region; 2, cool, hyposaline, shallow water conditions prevailed over much of Queensland; 3, open marine shelf conditions (of normal salinity) existed during the Albian in the Laura and northeastern Carpentaria Basins; and 4, during the Albian, at least, there was a northern seaway to the open ocean.  相似文献   

9.
We report overprinting stable isotope evidence of fluid–rock interaction below two detachment faults along which mantle rocks were exhumed to the seafloor, between the respective landward and seaward limits of oceanic and continental crust, at a Tethyan ocean–continent transition (OCT). This OCT, which is presently exposed in the Tasna nappe (south‐eastern Switzerland) is considered an on‐land analogue of the well‐studied Iberian OCT. We compare our results with the fault architecture (fault core–damage zone–protolith) described by Caine et al. [Geology (1996) Vol. 24, pp. 1025–1028]. We confirm the existence of a sharp boundary between the fault core and damage zone based on isotopic data, but the boundary between the damage zone and protolith is gradational. We identify evidence for: (1) pervasive isotopic modification to 8.4 ± 0.1‰ which accompanied or post‐dated serpentinization of these mantle rocks at an estimated temperature of 67–109°C, (2) either (i) partial isolation of some highly strained regions [fault core(s) and mylonite] from this pervasive isotopic modification, because of permeability reduction (Caine et al.) or (ii) subsequent isotopic modification caused by structurally channelled flow of warm fluids within these highly strained regions, because of permeability enhancement, and (3) isotopic modification, which is associated with extensive calcification at T = 54–100°C, primarily beneath the younger of the two detachment faults and post‐dating initial serpentinization. By comparing the volumetric extent of calcification with an experimentally verified model for calcite precipitation in veins, we conclude that calcification could have occurred in response to seawater infiltration, with a calculated flux rate of 0.1–0.2 m year?1 and a minimum duration of 0.2–4.0 × 104 years. The associated time‐averaged uptake flux of carbon during this period was 8–120 mol m?2 year?1. By comparison with the estimated area of exhumed mantle rocks at the Iberian OCT, we calculate a maximum annual uptake flux for carbon of 2–30 Tg year?1. This is an order of magnitude greater than that for carbon exchange at the mid‐ocean ridges and 0.1–1.4% of the global oceanic uptake flux for carbon.  相似文献   

10.
Iron finds from the Celtic oppidum of Manching in southern Bavaria (Germany) are analysed in view of their possible provenance. The exceptional size and the location of Manching are usually attributed to the presence of abundant iron ores in its vicinity. After a review of previous approaches for source determination of iron artefacts, we introduce lead isotope analysis as a new approach. However, only by combining the trace element patterns of slag inclusions and iron metal with lead isotope ratios in the metal is it possible to distinguish various iron ore formations near Manching. As a result, it turns out that, indeed, the most obvious ones—namely, bog ores near the Danube—constituted the main resources for iron production at Manching. It was even possible to select one occurrence as the most likely ore source.  相似文献   

11.
12.
The paper focuses on the seismic response of steel pin-jointed frames braced by lightweight cladding panels. In particular, with the aim to investigate the performance of such a structural scheme when acting as a dissipative system, a wide numerical study has been developed. It is based upon available shear tests on screwed sandwich panels, whose experimental cyclic responses are properly incorporated into a scope-oriented, computer program. The goal is firstly to check the possibility of using cladding panels as shear diaphragms in seismic areas and then to assess an appropriate design behaviour factor, accounting for their actual hysteretic response. Key findings from the nonlinear dynamic analyses are: (1) a portal frame steel building in a low-medium seismicity zone may be braced by common cladding panels, completely avoiding the use of other bracing systems; (2) this structural solution, if compared with a conventional one, appears to be more efficient and cost-effective, giving rise to a weight saving which, in the case under examination, reaches a value of about 20%; (3) on the basis of the numerical study a design behaviour factor q d =2 seems to be realistic for such a structural typology.  相似文献   

13.
This work illustrates the possible connections between the phenomenon of the seasonal emigration of lake masters and the production of artistic artefacts. Within the ambit of these dynamics, a stucco mantelpiece was taken into consideration. Nothing was known about the object: neither its origin, nor the artist who produced it, nor the period of execution. Historical, stylistic and formal analyses of the materials and of the technique with which the work was executed allow us to verify that the mantelpiece was produced using the stucco technique in the 17th century, in Rovio (southern Switzerland, Ticino), and that it comes from one of the exponents of the Carlone workshop, whose representatives were important in the tradition of itinerant artistic workers. Due to their good technical and professional specialization, the Carlone workshop served both public and private buyers. Tommaso Carlone is the principal representative artist of the Carlone workshop; it is certain that his workshop produced the stucco mantelpiece. The migrations of the artists were seasonal and they maintained a close bond with their country of origin. When they returned to the country of origin, they produced works of great artistic value, of which the mantelpiece represents a splendid example. Through the employment of conventional analytical techniques (optical and electron microscopy, infrared spectroscopy and porosity measurements), it has been possible to study the technique with which the work was executed, the materials used and the decay. The mantelpiece was produced using the stucco technique by means of a body layer (slaked lime and silicate and carbonate aggregates) and a marmorino finishing layer (slaked lime and pointed calcite crystals). Above this layer, whose thickness varies in relation to the executed result, there is a thin lime plaster whitewash, pigmented with the dispersion of yellow ochre particles; chromatic alterations are an oxalate patina caused by firm adhesion to the marmorino layer, due to the denaturation of the proteic substances employed. The final treatment was made with beeswax, which increased the marmoreal effect. Several additional layers of lime plaster whitewash have also been applied over the centuries. The figurative central square of the plastic decoration was made using red ochre.  相似文献   

14.
The evolution of littoral palaeoenvironments in the southern Pampas region of Argentina towards the end of the early Holocene and the beginning of the mid Holocene is discussed, and the formation processes of the archaeological site of La Olla are analysed. This site is located in the intertidal zone of the present beach and is remarkably well-preserved. The human occupation at the site has been dated at between 7400 and 6480 yrs BP, and is interpreted as a place for the processing and consumption of the southern fur seal (Arctocephalus australis) and southern sea-lion (Otaria flavescens). It is concluded that biostabilization by microbial mats of the sedimentary structures and archaeological remains that developed and are present on the tidal flat prevented their erosion by wind, turbulence currents and waves. This is what has permitted the exceptional preservation of the site. On the basis of the analyses of one of the sectors of the site it can be concluded that the sedimentary succession of the La Olla site is the result of the coastal environmental changes during the early–mid Holocene in the pre-maximum transgressive episode. During this interval a tidal flat developed on the Pleistocene abrasion platform. Human occupation occurred during the formation of mixohaline marsh, an upper intertidal–lower supratidal zone ecosystem.  相似文献   

15.
Intra‐tooth sequential analysis of enamel δ18O is currently used to investigate birth seasonality in past animal populations, offering new insights into seasonal availability of animal resources, herd management and seasonality of site occupation. Reference data sets are still required to address two major difficulties: (1) that inter‐individual variability in the record of the seasonal cycle is affected by tooth size; and (2) that the season of birth cannot be directly estimated from the timing of tooth growth, because of a delay in enamel mineralization. We present a data set acquired on the lower second molar of 10 modern sheep from Rousay (Orkney) born within a few weeks of each other in April/May and submitted to the same environmental conditions until death. All sheep have recorded a sinusoidal pattern of δ18O variation spanning approximately a year. From the difference between the expected and the measured time sequence, the delay of enamel mineralization is estimated to be 5–6 months. The data set is then described using a model mainly based on a cosine function. The period, corresponding to the length of the M2 crown formed over a year, averaged 35.8 mm. A very slight variation of tooth growth rate with time and no attenuation of the isotopic signal towards the cervical margin of the crown could be detected in this data set. The lowest δ18O values, corresponding to the sheep's first winter, were tracked at a distance from the enamel/root junction that varied between 23.0 and 30.3 mm (xmin mean = 27.6 mm); the highest δ18O values, corresponding to the sheep's second summer, were between 6.3 and 11.6 mm (xmax mean = 9.9 mm). Most of the variability can be attributed to tooth size. When normalized on the period, xmin and xmax are 0.28 (± 0.05) and 0.78 (± 0.05) on average, meaning that the Rousay sheep have recorded the minimum and maximum δ18O values on average at 78% and 28%, respectively, of the end of the periodic cycle recorded in the second molar.  相似文献   

16.
In December 1998, during excavation for the construction of a new building near San Rossore railway station in Pisa, the remains of ancient ships were discovered. These findings have been dated (radiocarbon) to between the end of the 10th century bc and the fifth century ad ( Belluomini et al. 2002 ). Several transport amphorae belonging to the Hellenistic ship, samples of rocks (stone ballast) belonging to ships B, D and the Hellenistic ship, and stowage materials belonging only to ship B have been analysed. The mineralogical and petrographic data of the investigated samples provided information on the possible provenance of the raw materials utilized in the manufacture of the ceramic amphorae, as well as on the provenance of the rock materials found in the ships as ballast and stowage. The compositional data (obtained through XRD, XRF, OM and EPMA) and their statistical analyses suggest that the provenance of the Dressel amphorae belonging to the Hellenistic ship was the Middle Tyrrhenian coast of Italy, and more precisely the area between Tarquinia and Naples, according to the numerous kilns and wine production sites found in this area. The provenance of the volcanic rocks was from southern Tuscany, northern Latium and possibly the Pontine Islands, whereas the intrusive rock possibly comes from the Calabrian–Tyrrhenian coast and/or the Peloritani area. The impure limestones and the dolostone come from southern Tuscany and the Latium coast; the semi‐metamorphic rocks could come from the coast of southern Tuscany, the Tuscan Archipelago or possibly also from the Ligurian coast; only the sample of mylonitized granitoid possibly comes from either the Calabria–Peloritani arc or the Tuscan Archipelago. The stowage materials, consisting of lapilli and scoria of a pyroclastic nature, are sourced from the Neapolitan area. These data might shed some light on the centres of production of the amphorae and of the trading routes followed by the ships, according to the ports of call.  相似文献   

17.
Cranial series from the Ust-Ishim burial grounds represent the medieval population of the southern taiga zone of the Middle Irtysh. Indirect data suggests that in the 5th–8th centuries AD, the area was populated by people akin to the low-faced Mongoloids who had lived in the Western Siberian forest steppe in the Early Iron Age. Apart from that, a very small Southern Siberian Mongoloid admixture is present. Generally, the Ust-Ishim people are similar to the Tobol–Irtysh group of populations belonging to the Ob–Irtysh variety of the Western Siberian race. Among the modern populations, those closest to the Ust-Ishim people are the Tobol-Irtysh Tatars, implying genetic continuity with the medieval groups studied by us.  相似文献   

18.
A program for forecasting the possible environmental consequences of industrial development in the Kansk-Achinsk Fuel and Energy Complex (KATEK) is described, the resulting forecasts providing the basis for recommendations for future resource development. Attention is focused on the projected impacts of the location of two state regional power stations (GRES) and one large strip mine in the Sharypovo area, the authors recommending that this represent the maximum capacity to be concentrated at any one location for environmental reasons. [Apparently, planners took this into consideration, as recently announced plans for the basin have been scaled back to include only two stations (see S.G., April 1988)—Ed., S.G.] One variant calls for the resiting of one of the GRES units to the eastern part of the KATEK area (translated by Natalia B. Barbash, Brooklyn, NY 11209).  相似文献   

19.
《Southeastern Archaeology》2013,32(1):134-147
Abstract

The Toqua site (40MR6) is one of the most thoroughly excavated Late Mississippian mound sites in East Tennessee. The site has been a focal point of research on late prehistory in southern Appalachia, but there are issues surrounding its chronological placement. The radiometric dates obtained for the site in the 1970s and the archaeomagnetic dates reported in 1999 have large standard deviations. These dates are too imprecise to be useful for a temporal placement of the site that is clear enough for current discussions of the development of Mississippian culture. A newly obtained Accelerator Mass Spectrometry (AMS) date from the large platform mound (Mound A) allows a reevaluation of the occupation sequence of the Toqua site. This date provides an anchor for a refined chronology for Mound A. In addition to the new AMS date, this refined chronology is based on complementary lines of evidence, including architectural evidence, mortuary practices, pottery traditions, and shell gorget styles.  相似文献   

20.
ABSTRACT

This investigation aggregates intact or reconstructed Gahagan bifaces from the southern Caddo area and central Texas to test the hypothesis that Gahagan biface morphology differs between the regions. The Gahagan bifaces (n=102) were scanned, then analyzed using a novel landmarking protocol and the tools of geometric morphometrics. Results provide a preview of the significant differences in Gahagan biface morphology expressed between the southern Caddo area and central Texas regions. The size discrepancy represents an inversion of current theoretical constructs that posit a decrease in tool size thought to articulate with an increase in distance from the raw material source. It is posited that the contrasting morphologies represent two discrete communities of practice; one (emergent Caddo horticulturalists) where Gahagan bifaces were enlisted primarily for burial and ritualistic activities, and the other (central Texas hunter-gatherers) where Gahagan bifaces were utilized over a longer time span in more practical and utilitarian contexts.  相似文献   

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