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1.
The management of the sea has increased exponentially in the last half-century, and different academic disciplines have been vital in shaping this management. Human geography, despite its explicit focus on the human–environment nexus, has so far had little impact on human relations with the sea. Based on empirical research conducted in England and Scotland, we argue that human geography is uniquely placed to offer effective solutions to marine resource management problems, and that geographers have the potential to offer key insights into how human populations can best interact with the living seas. Three of the most important current scholarly ‘imaginations’ of the sea, and the policies they inform (economics and market-based management, conservation biology and area based protection, and anthropology and community management), are outlined. A potential ‘geographical imagination’ of the sea, drawing on key themes in contemporary scholarship is then presented, and grounded in empirical research. It is argued that human–ocean relations should be a key feature of geographical research agendas. 相似文献
3.
Recently a few Japanese geographers became aware that the concept of nature in modern geography differs from that of traditional Japanese thought. As modern geography in Japan was formed by the influence of European geography, most academic geographers in Japan have followed the occidental view that proposed an opposition between cultural and natural landscapes and that, due to the belief in man's power, sees the former as superior to the latter. From an economic view point, in fact, the European concept of nature which is opposed to culture has contributed to land exploitation that caused the destruction of Japan's natural landscape.The time has come to consider the traditional Japanese idea of nature as Kami (gods) in comparison with the binary opposition of nature/culture which derives from modern rationalism. Kami who represent elements of nature belonged to a Pantheon in ancient Japan. Some examples of the Kami's names and their English explanations are as follows: Amaterasuomikami (godess of sun), Oyamatsumi-no-kami (god of the mountain's spirit), Nozuchi-no-kami (god of the field's spirit). In ancient Japan people believed that natural landscapes were created and inhabited by these Kami, and that the will of these Kami controlled the cultural domain. However, people provided shrines for Kami to placate their reckless domination. In this context, culture is in the hands of nature. This idea of nature's superiority to culture can explain the Japanese geographical concept of landscape. 相似文献
4.
We use the crystallographic orientations of quartz crystals, as determined with EBSD, to provide new evidence for the formation of clustered quartz crystals during magma crystallization. Vinalhaven is dominated by granite, with minor porphyry that formed when granite remelted during input of coeval basalt. CL zoning suggests that most quartz clusters in granite and porphyry formed by synneusis, the “swimming together” of preformed crystals. In granite, most quartz pairs in clusters have random orientations—only about 10% have parallel or Esterel twin orientations. Porphyry has fewer quartz clusters, and all pairs have approximately parallel or Esterel twin orientations. CL zoning of quartz pairs in porphyry indicates that they attached prior to a major remelting event. Interpretation of the Vinalhaven quartz clusters leads us to propose that oriented synneusis occurs during crystal accumulation on a magma chamber floor. During hindered settling, some quartz crystals should have come into contact along their dipyramidal faces. Once in contact, continued settling and loss of interstitial melt may have rotated some quartz crystals such that lattices on their dipyramidal faces matched—producing parallel and Esterel twin orientations and creating strong bonds between pairs. Only a small proportion of pairs with matched dipyramidal faces formed in the granite and, during rejuvenation to produce porphyry, only these oriented pairs survived. Hence, the presence of oriented synneusis in a plutonic rock may demonstrate a history of crystal accumulation. 相似文献
5.
Round sky and square earth is a basic concept in the tradition of ancient Chinese geography. It appeared at least two thousand years ago and has influenced Chinese geography significantly — both for good and for ill. As an academic subject in China, the history of geographical thought is new. It has become the center of geographical history (Yang 1989, p. 7; Wang 1982, p. 4). This transformation began in the 1980s. Earlier studies of the history of ancient Chinese geography paid more attention to the history of exploration, cartography, and geographers themselves. It neglected serious study of the concept and influence of the idea of round sky and square earth. This paper discusses this concept, its influence on ancient Chinese cartography, and its significance in early geographical literature, specifically the Geographical Society Yu Gong (Tribute of Yu). 相似文献
6.
In this paper, we reflect on an emerging community-based partnership rooted in place-based reparative research. Braiding knowledges (Atalay, 2012) from Nbisiing Anishinaabeg communities, northern Ontario universities, and multi-scalar museums, the partnership focuses on repatriation, reparative environmental histories, and action-based research in the context of settler colonialism and climate change. We reflect on ongoing projects that attempt to put Anishinaabe gikendaasowin (knowledge) into action alongside historical geographical research. We discuss how the partnership resonates with community geography values of relationship, collaboration, equity, and reciprocity, and urge non-Indigenous geographers to acknowledge how Indigenous knowledges and approaches have shaped these ideas long before geography became a discipline. We contend that historical geographers have a deeper role to play in community geography scholarship, citing examples of two projects related to (1) repatriation of Anishinaabeg cultural heritage and (2) storymapping through historical Geographic Information Systems (HGIS). However, we argue, geographers must continue to acknowledge their own positionality in a discipline that was built through settler colonial violence and knowledge production. Finally, we reflect on the role of academic institutions in facilitating First Nation-university-museum partnerships through access to funding, space, and databases, while addressing the challenges of relying on institutional support for reparatory and decolonizing projects. 相似文献
7.
Conclusion This review must be seen alongside others which have attempted to explore the relationship between geography (and geographers) and the study of leisure and recreation (Coppock 1980, 1982a). It serves to confirm the wide-ranging and diverse contribution that geographers have made in this field and the ways in which the study of tourism has reflected developments in the wider discipline. It also confirms the very close and intimate connection between studies of tourism and social and economic policy in Britain and indicates the way in which geographers have attempted to shape policy and have in turn been influenced by the needs and demands of policymakers. The rewards of such interaction are clear and yet costs have also been incurred by the academic geographic community. Not the least of these costs is that tourism studies have been predominantly of an empirical nature and conceptual and theoretical advance has inevitably tended to lag behind these empirical investigations. It is to be hoped that the study of the geography of tourism, having now demonstrated its credentials to policymakers and decision-makers alike, can secure for itself a more central place within geographic teaching and research so that these lacunae can be remedied. 相似文献
8.
The new `geographical economics' introduced by Paul Krugman and others has been dismissed by geographers for a number of reasons, ranging from (mis)treatment of externalities to reliance on formal modelling. These criticisms may be appropriate, but they miss some underlying unit assumptions that cause geographical economics to deal poorly with issues of scale and space. The theories produced by Krugman and others rely on the economic units of the firm, industry and economy for analysis. In contrast, geographers often use spatial units which not only reveal different processes, but can also delimit the economic units. Acknowledgement of the difference in the assumed units of analysis between geographical economics and economic geography is necessary before any useful discourse between the two fields can occur. 相似文献
9.
Geographic knowledge is usually understood as the knowledge produced by geographers. Yet, it is also produced by people outside
of the academia. But as Western science claimed for its exclusive self the status of ‘knowledge’, others have long been denied
the production and possession of a true knowledge, and recognised merely the mastering of practical skills. The binary opposition
between scientific and other forms of knowledge has been central to the construction of academic geography until the late
1980s, when postmodern thought cast some doubt on the universality of scientific knowledge. This led to critical analyses
of academic geography, revealing its situatedness, as well as to a new interest for the geographies of the ‘Others’. Examining
how geographers have dealt with other knowledge sets so far, and how they have labelled them, this paper argues that other
geographies should be given more attention. This means focusing on the knowledges themselves, and considering implementing
a true dialogue between these and academic geography.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Possible paths for the formation of Ap/Bp stars—massive main-sequence stars with strong magnetic fields—are analyzed based
on modern theories for the evolution of single and binary stars. Assuming that the strong magnetic fields of these stars are
the main reason for their comparatively slow axial rotation and the observed anomalies in the chemical compositions of their
atmospheres, possible origins for these high magnetic fields are considered. Analysis of several possible scenarios for the
formation of these stars leads to the conclusion that their surface magnetic fields are probably generated in the convective
envelopes of the precursor stars. These precursors may be young, single stars with masses 1.5–3 M
⊙ that formed at the peripheries of forming star clusters and ended their accretion at the Hayashi boundary, or alternatively
close binaries whose components have convective envelopes, whose merger leads to the formation of an Ap/Bp star. Arguments
are presented supporting the view that the merger of close binaries is the main channel for the formation of Ap/Bp stars,
and a detailed analysis of this scenario is presented. The initial major axes of the merging binary systems must be in the
range 6–12 R
⊙, and the masses of their components in the range 0.7–1.5 M
⊙. When the merging components possess developed convective envelopes and fairly strong initial magnetic fields, these can
generate powerful magnetic fields “inherited” by the products of the merger—Ap/Bp stars. The reason the components of the
close binaries merge is a loss of angular momentum via the magnetic stellar winds of the components. 相似文献
12.
Of the many diverse sources of naturalistic thinking in early modern geography, the penetration of Darwinian evolution is conventionally regarded as one of the most influential. In its application to social processes, the term ‘Social Darwinism’, as it is generally designated, has been used to describe almost any evolutionary perspective on human society. In its most common form, ‘Social Darwinism’ (or ‘Business Darwinism’, as some have designated it) has been portrayed as an attempt to provide ‘scientific’ justification for the cut-throat ethics of late nineteenth century capitalism. The main contention of this essay is that the widespread use of the term ‘Social Darwinism’, has obscured the variety of other ways in which biological analogies were applied to society, and that one of the most influential of these was the social model erected on the Lamarckian evolutionary alternative — a version of evolutionary biology widely espoused by geographers in Britain and America. Social Lamarckism, by emphasizing the cumulation of social improvements, repudiated the non-interventionism of ‘Social Darwinism’ and was used by many geographers to underpin their support for numerous educational, eugenic and environmental movements to improve the condition of humanity. And while biologically bankrupt, the Lamarckian social schema continues to be invoked as a viable model of society's evolution. 相似文献
13.
We present images of the star-forming regionG23.01–0.41 at 6.7GHz in the Class II methanol maser transition 5 1–6 0
A
+, produced from archival observations on the European VLBI Network. Our map of the source and its maser spots contains 24
maser components. The data for each spot—absolute coordinates, coordinates relative to the calibration feature, peak flux
and flux integrated over the spot, size, position angle, velocity along the line of sight, and line full width at half-maximum—are
collected in tabular form. The spatial region occupied by the maser spots is approximated by a 200×130 milliarcsec ellipse
in position angle PA = −0.40°, centered on the absolute coordinates α
0 = 18 h34 m40.282 s, δ
0 = −09°00′38.27″ (J2000). If the source is a protoplanetary disk, then, for the distance estimate derived from trigonometric
parallax, its diameter is 1800 AU, and the mass of the central protostar is 23.5 M
⊙. 相似文献
14.
Graphite-bearing rocks and graphites from the Precambrian metamorphic sequence of the Pestpaksha ore occurrence, Murmansk
district, have been studied by the X-ray method. It was determined that the rocks have a complex polycomponent composition.
Graphite is associated with garnet-quartz, pyroxene-amphibole, and biotite-quartz with an admixture of pyrrhotite, kyanite,
chlorite, and other minerals. In terms of mineral composition, the studied samples are subdivided into five groups. The structural
characteristics of graphite—parameters a
0 and c
0, the degree of structural perfection (U), the content of rhombohedral phase (R), and others—were found to be different for
each group. The U value varies from 1.04 to 1.56 (with predominant values from 1.4 to 1.5), while the content of rhombohedral
phase in samples is no more than 18%. This fact indicates a relatively high 3D order, which is typical of graphites from metamorphic
rocks. Graphites from metasomatites have the lowest U value, while those from weathering zones are characterized by a small
value of the coherent scattering domain (CSD). It was established that interplanar spacing d
002 of graphite correlates with depth, while the degree of ductility and flexibility of the graphite is defined by conditions
of its retrograde metamorphism. 相似文献
15.
The dependence of iron and europium partitioning between plagioclase and melt on oxygen fugacity was studied in the system
SiO 2(Qz)—NaAlSi 3O 8(Ab)—CaAl 2Si 2O 8(An)—H 2O. Experiments were performed at 500 MPa and 850 °C/750 °C under water saturated conditions. The oxygen fugacity was varied
in the log f
O2-range from −7.27 to −15.78. To work at the most reducing conditions the classical double-capsule technique was modified.
The sample and a C—O—H bearing sensor capsule were placed next to each other within a BN jacket to minimise loss of hydrogen
to the vessel atmosphere. By this setup redox conditions slightly more reducing than the FeO—Fe 3O 4 buffer could be maintained even in 96 h runs. Raman spectra showed that the BN was modified by reaction with hydrogen resulting
in a low hydrogen permeability. The partition coefficients determined for Eu at 850 °C and 500 MPa vary from 0.095 at conditions
of the Cu—Cu 2O buffer to 1.81 at the most reducing conditions (C—O—H sensor). In the same f
O2 interval the partition coefficient for Fe varies from 0.55 at oxidising conditions to 0.08 at the most reducing conditions.
The partitioning of Sm, which was added as a reference for a trivalent REE, does not vary with the oxygen fugacity, yielding
an average value for D = 0.07. Lowering the temperature to 750 °C for a given f
O2 decreases the partition coefficient of Eu and increases that of Fe. Comparison with published data at 1 atm and at higher
temperatures shows that both temperature and composition of the melt have strong effects on the partitioning behaviour. As
the change of the partition coefficients in the geologically relevant f
O2 range is quite strong, element partitioning of Eu and Fe might be used to estimate redox conditions for the genesis of igneous
rocks. Furthermore, by modelling the partitioning data it is possible to extract information about the redox state of the
melt. Resulting ferric-ferrous ratios show significant differences from those predicted by empirical models.
Received: 14 October 1998 / Received: 5 March 1999 相似文献
16.
Diatoms from surface sediment samples collected from Enderby Basin of Indian Sector of Southern Ocean were analyzed to determine
the relative abundance and distribution of seven key indicator diatom species viz. Sea ice related species Fragilariopsis rhombica, F. separanda, F. curta, F. ritscheri, Thalassiosira tumida and Actinocyclus actinochilus and Open Ocean species F. kerguelensis on the basis of modern physico-chemical parameters. The relative abundances of different species observed viz. F. rhombica — 6.25%; F. separanda — 12.5%; F. curta — 10.53–13.33%; F. ritscheri — 4.55–12.5%; F. kerguelensis — 6.25–63.64%; T. tumida — 3.13% and A. actinochilus — 9.38–13.33%. The increasing abundance of F. kerguelensis consecutively suggests the effect of Antarctic bottom water in the study area which is further substantiated by the presence
and increasing abundance of F. ritscheri. The gradual decrease in abundance or absence of sea ice related species from the sampled stations indicates the summer and
winter sea ice extent concentration in the study area. The nutrient concentration correlates with the distribution and abundances
of diatom species. 相似文献
17.
We have analyzed light curves from the MOST satellite for the two active dwarfs ɛ Eri and κ Cet. Our maps of the stellar surface-temperature inhomogeneities were obtained with no a priori assumptions about the shape,
configuration, and number of spots. We find variations of the surface-temperature inhomogeneities with time, also on time
scales about equal to their rotation periods. We consider a model of a spotted star with two types of surface inhomogeneities—spots
and related plage fields—and demonstrate that the best agreement between the theoretical and observed light curves is achieved
for small ratios of the plage-field area to the area of cool spots. This conclusion indicates that long-term brightness variations
of stars younger than the Sun are mainly due to variable spots on their surfaces, while the contribution from plage fields
becomes more significant for older stars. 相似文献
18.
A new method is proposed for the development of a class of elastoplastic thermomicromechanical constitutive laws for granular
materials. The method engenders physical transparency in the constitutive formulation of multiscale phenomena from the particle
to bulk. We demonstrate this approach for dense, cohesionless granular media under quasi-static loading conditions. The resulting
constitutive law—expressed solely in terms of particle scale properties—is the first of its kind. Micromechanical relations
for the internal variables, tied to nonaffine deformation, and their evolution laws, are derived from a structural mechanical
analysis of a particular mesoscopic event: confined, elastoplastic buckling of a force chain. It is shown that the constitutive
law can reproduce the defining behavior of strain-softening under dilatation in both the mesoscopic and macroscopic scales,
and reliably predict the formation and evolution of shear bands. The thickness and angle of the shear band, the distribution
of particle rotation and the evolution of the normal contact force anisotropy inside the band, are consistent with those observed in discrete element simulations and physical experiments. 相似文献
19.
The purpose of this study was to investigate the concentration levels of heavy metals in different species of the main three
marine algal divisions from the Gulf of Aden coastal waters, Yemen. The divisions included Chlorophyta—green plants ( Halimeda tuna, Rhizoclonium kochiamum, Caldophora koiei, Enteromorpha compressa, and Caulerpa racemosa species), Phaeophyta—brown seaweeds ( Padina boryana, Turbinaria elatensis, Sargassum binderi, Cystoseira myrica, and Sargassum boveanum species), and Rhodophyta—red seaweeds ( Hypnea cornuta, Champia parvula, Galaxaura marginate, Laurencia paniculata, Gracilaria foliifere, and species). The heavy metals, which included cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), Iron (Fe), manganese
(Mn), nickel (Ni), lead (Pb), zinc (Zn), and vanadium (V) were measured by Atomic Absorption Spectrophotometer (AAs). The
concentrations of heavy metals in all algal species are in the order of Fe >> Cu > Mn > Cr > Zn > Ni > Pb > Cd > V > Co. The
results also showed that the uptake of heavy metals by different marine algal divisions was in the order of Chlorophyta > Phaeophyta > Rhodophyta.
These heavy metals were several order of magnitude higher than the concentrations of the same metals in seawater. This indicates
that marine alga progressively uptake heavy metals from seawater. 相似文献
20.
The purpose of the so-called IFFI project ( Inventario dei Fenomeni Franosi in Italia—Inventory of Landslides in Italy) and of many other related activities carried out by the Centro Regionale per le Ricerche Territoriali e Geologiche of ARPA Piemonte ( Agenzia Regionale per la Protezione Ambientale—Regional Agency for Environmental Protection), is to map all the existing landslides in Piemonte (including both results of monitoring data and available historical data). ARPA carried out new systematic surveys using
airphoto interpretation and created a specific alphanumeric geological information systems (GIS)-based database to store and
process all the collected data. In order to obtain proper landslide-hazard zoning, it is necessary to provide a landslide
inventory and to define the relationship between landslides and geological setting. A landslide inventory represents a fundamental
base of knowledge, is a very basic tool for land planning, and strongly helps the local authorities in their decision making. 相似文献
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