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921.
This article deals with women's use of public space and sense of place in El Raval, a neighbourhood located in the historical
center of Barcelona. Attention will be paid to discover to what degree the existence of a quality public space fosters the
creation of socially meaningful places, thus contributing to the construction of womens sense of place and urban identities.
A qualitative approach, based on direct observation and in-depth interviews with women living in the neighbourhood, has allowed
us to capture the main aspects of the building of a sense of place and belonging, that is the use of public space and facilities,
the attitude towards living in the neighbourhood, etc.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
922.
Ninad R. Bondre Raymond A. Duraiswami Gauri Dole 《Journal of Earth System Science》2004,113(4):809-817
The nature and style of emplacement of Continental Flood Basalt (CFB) lava flows has been a matter of great interest as well
as considerable controversy in the recent past. However, even a cursory review of published literature reveals that the Columbia
River Basalt Group (CRBG) and Hawaiian volcanoes provide most of the data relevant to this topic. It is interesting to note,
however, that the CRBG lava flows and their palaeotopographic control is atypical of other CFB provinces in the world. In
this paper, we first present a short overview of important studies pertaining to the emplacement of flood basalt flows. We
then briefly review the morphology of lava flows from the Deccan Volcanic Province (DVP) and the Columbia-Oregon Plateau flood
basalts. The review underscores the existence of significant variations in lava flow morphology between different provinces,
and even within the same province. It is quite likely that there were more than one way of emplacing the voluminous and extensive
CFB lava flows. We argue that the establishment of general models of emplacement must be based on a comprehensive documentation
of lava flow morphology from all CFB provinces. 相似文献
923.
Helen Ruth Aspaas 《GeoJournal》2004,61(3):281-289
Women in many rural areas of the US often engage in small-scale businesses as one of several avenues for contributing to household
incomes. In those geographical areas that contain a significant minority population, many of the women's businesses display
the cultural diversity of the regions in which they live. Likewise, women's roles as economic providers as well as wives and
mothers are reflected in the manner in which they operate their businesses. Candida Brush suggests that women's strategies
for operating their businesses are highly integrative because women's business decisions are intertwined with familial responsibilities,
household economic demands and desires to contribute to their communities. Hispanic and Native American women in the Four
Corners region of southwestern US and African American women in central Virginia participated in interviews in which they
responded to numerous short answer and open-ended questions about their businesses and decision-making strategies. From these
interviews an image emerges of rural minority business women who are operating their businesses at the nexus of family obligations,
economic necessities, cultural ties and with a commitment for serving their communities.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
924.
925.
ZHAO Pengda 《中国地质大学学报(英文版)》2004,15(3):245-252
“Three-component” method consists of three clase-connected aspects: geological anomaly,diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, oreexisting symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a “digital model“ for mineral resources prediction andassessment. 相似文献
926.
Asynchronous Holocene climatic change across China 总被引:1,自引:0,他引:1
A review of Holocene climatic variations in different parts of China shows that they were asynchronous. Proxy data from ice cores, pollen, loess, lacustrine sediments, and changes of sea and lake levels demonstrate that many warm and cold oscillations have occurred in China during the Holocene, including a most important climatic event known as the “Holocene optimum,” a milder and wetter period, and that the duration and amplitude of the optimum period, as well as its start and end times, differed in different parts of China. Uplift of the Tibetan plateau over the past millions of years led to the development of the monsoon climate and to complex atmospheric circulation over continental China during the Holocene. As a result, the Holocene optimum began and terminated earlier in high-altitude regions of western China than at lower elevations in eastern China, and the amplitude of the variations was lower in the east. This suggests that the western higher-altitude areas were more sensitive to climatic change than were the eastern lower-altitude areas. Holocene climatic records in the Dunde and Guliya ice cores do not correspond. Inverse δ18O variations between the two cores indicate that the effects of climate and atmospheric processes on the stable isotopes at the two sites differed. The correlation between the isotopic composition of carbonates in lake deposits in western China and climatic variations is similar to that in the ice cores. The climatic resolution in ice cores and lake sediments is higher than that in other media. The lack of precise correspondence of climatic records constructed on the basis of proxy data from different parts of China is a result of the different locations and elevations of the sampling sites, the different resolutions of the source material, and the varied climatic conditions within China. Further work is needed to confirm both the conclusions and the inferences presented here. 相似文献
927.
Chen-Tung Arthur Chen Jiunn-Tzong Wu Bing-Jye Wang Kuo-Ming Huang 《Aquatic Geochemistry》2004,10(1-2):33-57
One hundred and eighty lakes, ponds and reservoirs in Taiwan, and the offshore islands have been investigated since 1985. Effects such as warming/cooling, mixing, photosynthesis and respiration on pH have been identified. These effects were found to be less profound than those resulting from the geology. Since there is little rain or lake water pH data available prior to 1970, it was necessary to use proxy data in order to ascertain the history of lake acidification. In this study, we present data based on diatoms in a sediment core collected from a lake in the remote subalpine region of southern Taiwan. The acidity of this lake water was found to have increased since 1900. We measured the concentrations of 55 chemical species in lake water samples. In addition, concentrations of 26 chemical species were obtained from sediments. Conductivity, alkalinity (HCO3 ?), most other major and minor chemical species, as well as the non sea-salt SO4/Na ratio in lake water clearly decrease with elevation. Distribution of pH is similar, although the trend is less clear. Distribution of trace metals, however, shows a different trend as anthropogenic pollution, diagenetic reduction and lake acidification are at play. 相似文献
928.
Evidence for focused hot fluid flow within the Britannia Field, offshore Scotland, UK 总被引:1,自引:0,他引:1
S. G. Archer H. L. Wycherley G. R. Watt M. L. Baron J. Parnell H. Chen 《Basin Research》2004,16(3):377-395
Fluid inclusion and scanning electron microscope‐cathodoluminescence evidence indicates focused hot, saline, diagenetic fluid flow within the Eastern Flank of the Britannia Field, offshore Scotland, UK. The fluid was sourced from the Andrew Salt Dome, 10 km to the east. The fluids, which promoted quartz cementation of the upper zones within the field, were up to ~30°C hotter and had salinities up to ~10 wt% NaCl equivalent higher than fluids from lower in the reservoir section. During diagenesis hot saline fluids migrated westwards as part of a radiating ‘diagenetic front’ from the Andrew Salt Dome. Structural dip associated with the Eastern Flank of the Fladen Ground Spur impeded the westward movement of the diagenetic fluid. The quartz cements from the upper and lower reservoir zones can be distinguished by morphology. In the upper zones the quartz cements have well‐developed macro‐crystalline zoning and heterogeneous luminescence across the grain. In the lower zones, the cements are much less developed, unzoned and very weakly luminescent. The diagenetic fluids were primarily focused into Zone 45 within the upper reservoir. Furthermore, within the Main Platform Area the most prolific producing zone is Zone 45, indicating the importance of this interval as a permeable flow unit during both diagenetic and production timescales. Within the Eastern Flank, the quartz overgrowths have a major impact on reservoir permeability and thus well productivity. The overgrowths are most extensive in the originally clean sandstones with low clay content. Clay in optimum volumes (5–10%) can inhibit nucleation of the damaging quartz overgrowths without having a detrimental effect on pore connectivity. These observations provide a predictive concept for use in the search for relative reservoir sweetspots within the degraded Eastern Flank. 相似文献
929.
930.
Pollution history and recovery of a boreal lake exposed to a heavy bleached pulping effluent load 总被引:4,自引:0,他引:4
Juhani Hynynen Arja Palomäki Jarmo J. Meriläinen Allan Witick Keijo Mäntykoski 《Journal of Paleolimnology》2004,32(4):351-374
We examined the effects of heavy pulp mill discharges on the Lake Lievestuoreenjärvi ecosystem and the later recovery of diatom and chironomid communities from age-dated short core samples. Beginning in 1927 the lake received a heavy effluent load from a sulphite pulp mill. Except for the recession during the Second World War and the temporary closure of the mill from 1967 to 1971, the industrial load, containing large quantities of nutrients, organic matter and toxic compounds, increased continuously. In the early 1980s, laboratory documents were falsified by the directors of the mill and the systematic illegal effluent overload led to a collapse of the whole lake ecosystem. In 1985, the outdated plant was finally closed down. Based on the assessment of chemical properties and biological remains of the sediment, we distinguished five developmental phases in the ecological state of the lake. In the pre-industrial phase, the pelagic and profundal benthic communities were dominated by species preferring ultraoligotrophic or oligotrophic lakes. Concomitant with the increasing discharge and deposition of chlorine compounds, resin acids, and mercury, as well as strong acidity and hypolimnetic and epilimnetic anoxia, the ecological status changed in a short period from excellent to bad. Finally, in the early 1960s, the majority of the lake was virtually dead and the aquatic life survived only in the uppermost littoral zone. Since 1985, a fast recovery in the water quality has led to a strong, but temporary eutrophy in pelagic communities. The main peak of eutrophication was caused by the invasion of a species new to the lake,Aulacoseira granulata var.angustissima. Later, the pelagic communities shifted towards oligotrophy, but the original, pre-industrial status has not been re-established. The profundal benthic communities have not achieved the pre-industrial structure, but at present indicate mesotrophy. 相似文献