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1.
Amenity migration: diverse conceptualizations of drivers,socioeconomic dimensions,and emerging challenges 总被引：7，自引：0，他引：7
Rural communities throughout the postindustrial world are in the midst of a significant transition, sometimes referred to
as rural restructuring, as traditional land uses, economic activities, and social arrangements transition to those associated
with “post-productivist” or “multifunctional” landscapes. Amenity migration, the movement of people based on the draw of natural
and/or cultural amenities, can be thought of as both driver and implication of this transition, resulting in significant changes
in the ownership, use, and governance of rural lands, as well as in the composition and socioeconomic dynamics of rural communities.
In concert with other social, economic and political processes, amenity migration is contributing to the fundamental transformation
of rural communities throughout the world. This paper presents a review of the social science literature related to the concept
of amenity migration, focusing on the ways in which it has been conceptualized, theorized, and documented by different communities
of scholars. We then profile and summarize diverse perspectives on drivers and socioeconomic impacts, highlighting emerging
challenges and opportunities related to this type of migration occurring at multiple scales and in multiple sites. The paper
also identifies and discusses particular areas where further research is needed. 相似文献
2.
From brain drain to brain gain: reverse migration to Bangalore and Hyderabad, India’s globalizing high tech cities 总被引：1，自引：0，他引：1
Elizabeth Chacko 《GeoJournal》2007,68(2-3):131-140
This paper assesses the mutual impact of returning Indian-origin skilled workers on the cities of Bangalore (Bengaluru) and
Hyderabad, which have emerged as India’s leading “tech cities”. During the 1970s and 1980s, there was concern that India was
losing its educated workforce to the West, particularly to the United States through a phenomenon known as “brain drain”.
More recently, there is evidence that reverse brain drain is occurring, as U.S.-trained Indian professionals are returning
to their home country in increasing numbers to take advantage of new growth and employment opportunities. The effects of this
skilled, transnationally active labor force on various sectors of the economy, on the social and physical infrastructure of
Bangalore and Hyderabad and in forging and solidifying transnational linkages between India and the United States are explored
in this paper. This study also investigates the reasons why successful US professionals of Asian-Indian origin are returning
to their home country via a series of personal interviews. The paper offers Bangalore and Hyderabad as “worldwide leading
cities” with a niche status in the global Information Technology (IT) sector. 相似文献
3.
In this work some examples of “twisting” of the Earth in the geologic past are given: displacement of the northern parts of
the global submeridional structures to the west relative to their southern parts; the rotation of the “geodynamic pair” of
Siberia-Laurentia in the Proterozoic; sinistral displacement of the Northern Hemisphere relative to the Southern Hemisphere
after the collapse of the last Pangaea; the equatorial rotation of the continental plates; oblique orientation of the global
network of planetary fracturing; an inclination of the axis of submeridional compression; sinistral “beveling”; the dextral
“twisting” of Venus. All these examples confirm the idea of possible sinistral “twisting” of the Earth that has been proposed
by many authors. The cause of such “twisting” is unclear, although it is likely connected with the Earth’s rotation around
its axis. Some of these examples show that many paleomagnetic reconstructions can be usefully discussed in a tectonophysical
aspect. Moreover, in connection with this data, the development of a new scientific field, called “paleomagnetic tectonophysics”, is possible. 相似文献
4.
The sediment-hosted disseminated gold deposits in the Oinling region are of sedimentation-slight-metamorphic origin superimposed by hydrothermal reworking at moderate-low temperatures and are well comparable with the typical Carlin gold deposits in the United States.In view of the confusing concept concerning the “sediment-hosted”and “Carlin-type” gold deposits,the authors propose that the term“sediment-hosted gold deposit”should be used in a broad sense which encompasses at least the four subtypes,i.e.,the Carlin type,the metamorphic fine clastic type,the hydrothermal sedimentary type and the vein type.In oter words,the “Carlin-type”should not be used as a synonym for “sediment-hosted”but is recommended as a subtype under the general category of “sediment-hosted gold deposits” 相似文献
5.
Gerald R. North 《GeoJournal》2007,70(1):27-31
An Inconvenient Truth provides an opportunity to examine the differences between scientific statements and the mixed statements made by politicians.
The Gore movie is a powerful example of the latter. There are some inaccuracies and exaggerations in the film, but on the
whole it represents mainstream scientific views on global warming. This essay looks into the state of the art of climate change
research including its scientific underpinnings. Climate science is in a state of ‘normal science’ as discussed by Kuhn. There
is a large body of scientists who are adherents to the paradigm and there does not appear to be any serious alternative at
this time. 相似文献
6.
The World Landslide Forum (WLF) is a triennial mainstream conference aimed at gathering scientists, stakeholders, policy makers
and industry members dealing with the management of landslide risk. The First World Landslide Forum, organised by the International
Consortium of Landslides, UNESCO, WMO, Food and Agriculture Organization, UNISDR, UNU, UNEP, IBRD, UNDP, ICSU, WFEO, KU and
the Japan Landslide Society, was held in 2008 at the United Nations University, Tokyo. The 1st WLF adopted the 2008 Tokyo
Declaration “Strengthening the International Programme on Landslides with UNISDR”. The Second World Landslide Forum has the
objective to further develop the outcomes of the First Forum in Tokyo 2008 by providing a global cross-cutting information
and cooperation platform for all types of organisations representing academia, United Nations organisations, governments,
private enterprises and individuals that contribute to landslide research, practice, education and decision making and are
willing to strengthen landslide and other related Earth system risk reduction strategies. The emphasis of this forum will
be “Putting Science into Practice” with special attention given to actual implementation of technology and research in everyday
applications and procedures with the direct involvement of researchers, engineers, private enterprises, stakeholders as well
as policy and decision makers. The abstract submission and pre-registration of participants was quite successful with 649
received abstracts and more than 800 participants at May 2011. The full organisation of the event is now in progress taking
into consideration the new figure and interest in scientific community and stakeholders. 相似文献
7.
Nancy Krieger 《GeoJournal》2009,74(2):87-97
To put on the map: according to the Oxford English Dictionary, whatever is so placed occupies “an important or prominent position” and is “of
some account or importance.” In this brief commentary, I take the opportunity to reflect on several articles by medical/health
geographers and others regarding our Public Health Disparities Geocoding Project and my research, as a social epidemiologist, on the myriad ways racism can harm health. In both cases, my work on these topics
has been motivated by my desire, starting a quarter of a century ago, to put health inequities on the map: as a topic of public
concern, research, and action. The insightful and informative points and questions raised by the geography-oriented articles
underscore the importance of bringing the best of our respective disciplinary insights and expertise to illuminate the profound
connections between social justice and public health, between our bodily truths and the body politic, so as to further the
goal of embodying equity––in an ecologically sustainable world. 相似文献
8.
Emphasis has been given to a number of aspects which characterise technological development in today's economic systems and
which have an impact on the working environment and on gender differences. Technological change is leading to a strong divide
between knowledge “producers” and “users”. The possibility of access to one or both knowledge systems indicates the extent
of women's participation in the economic and spatial transformations brought about by the new technologies. This research
aims to analyse the development of new technologies and the presence of the female workforce in the field of new knowledge
generation, and also to verify gender-related conditions in learning and using new technologies. In particular, an analysis
has been carried out of the empirical case study of Pisa, a point of reference for comparisons with other Italian and European
cases. The research focuses on: the examination of women's capabilities in the field of new technologies through the analysis
of University training courses; the analysis of women's presence and status among the university staff, especially in science
and technology; a detailed survey of female employment in innovative sectors. The results of the research emphasise the gender
perspectives of inclusion — as regards the application of technologies — and exclusion — as regards the generation of knowledge
— of women in or from new technologies. At the same time, the research stresses the growth of women's roles in this sector
during recent years and, by reconstructing life histories, underlines the conditions and difficulties that have been met by
women entering these new types of employment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
This study is part of the hazards mitigation education program “research on teaching resources development and curriculum
promotion on natural hazards mitigation at high school level.” This study demonstrated the implementation of a newly developed
earth science curriculum module of typhoon hazards mitigation in a 10th grade high school classroom in Taiwan. The curriculum
module design is a response to the calls for better natural hazards mitigation education in the school systems in Taiwan.
Findings show that the curriculum module has resulted in the positive learning outcomes in both students’ learning achievement
and attitude toward typhoon hazards mitigation. Findings also suggest that group discussion activities could enhance students’
thinking and experience sharing on the perceptions about typhoon hazards preparedness and mitigation. This study suggests
that the hazards mitigation curriculum module to be added as a topic in the national high school curriculum guidelines. 相似文献
10.
Kalliopi Sapountzaki 《Natural Hazards》2012,60(3):1267-1285
The article decodes and analyzes the standard functions of social and social-ecological systems when they manage their own
vulnerability. The author acknowledges these as “Resilience functions” or “Operational Resilience”. For this purpose, she
follows a “Vulnerability Actor” (V Actor)-based approach. V Actor is considered as a system faced with multiple hazards, carrying
various vulnerability facets (physical, economic, institutional, etc.) and attempting to transform, transfer, rearrange them
in time and space so as to achieve Actor’s own persistence. It is these processes of vulnerability re-arrangement that are
identified by the author as Resilience functions and which change the vulnerability not only of the V Actor performing resilience
but also others’. Performance of Resilience functions presupposes attraction and employment of resources by the Actor, not
only own, current and inherent but also other resources to be found in spatial and temporal scales external to or beyond the
Actor but which the Actor can appeal to. This attraction most probably leads to deprivation of others of the necessary resources
for their persistence, recovery, etc. When somebody’ vulnerability is reduced sometimes somewhere, it is most probable that
others elsewhere are encumbered with extra vulnerability, currently or in the future. Hence, what resilience can only do is
vulnerability re-arrangement, re-setting and management. The proposed systemic approach is documented on current state of
art regarding interactions between vulnerability and resilience to hazards and on empirical evidence from the international
experience of responses to natural hazards. 相似文献
11.
Rahul Ramachandran Manil Maskey Ajinkya Kulkarni Helen Conover U. S. Nair Sunil Movva 《Earth Science Informatics》2012,5(1):33-41
“Open science,” where researchers share and publish every element of their research process in addition to the final results,
can foster novel ways of collaboration among researchers and has the potential to spontaneously create new virtual research
collaborations. Based on scientific interest, these new virtual research collaborations can cut across traditional boundaries
such as institutions and organizations. Advances in technology allow for software tools that can be used by different research
groups and institutions to build and support virtual collaborations and infuse open science. This paper describes Talkoot,
a software toolkit designed and developed by the authors to provide Earth Science researchers a ready-to-use knowledge management
environment and an online platform for collaboration. Talkoot allows Earth Science researchers a means to systematically gather,
tag and share their data, analysis workflows and research notes. These Talkoot features are designed to foster rapid knowledge
sharing within a virtual community. Talkoot can be utilized by small to medium sized groups and research centers, as well
as large enterprises such a national laboratories and federal agencies. 相似文献
12.
Shumei XU Shikui ZHAI Aibin ZHANG Huaijing ZHANG Haijian LU 《Frontiers of Earth Science》2008,2(1):10-16
The grain size and element (including redox sensitive elements and terrigenous elements) concentration of surface sediments
from the Changjiang Estuary hypoxia zone and its adjacent sea area were measured in this research. Based on the obtained data,
the hypoxic environment’s influence on the distribution of elements in surface sediments was further studied. We believe that
the “redox environment effect” greatly influences the distribution of the RSE, which reveals the “patchy enrichment pattern”
offshore in the hypoxia zone, while the distribution of the terrigenous elements which shows the “stripped enrichment pattern”
near shore is mainly affected by “granularity effects”. Due to the existence of the hypoxia zone of the Changjiang Estuary,
the distribution of the RSE such as Mo, Cd and V in the study area exhibits the characteristics of “redox environment effects”.
__________
Translated from Marine Geology & Quaternary Geology, 2007, 27(3):1–8 [译自: 海洋地质与第四纪地质] 相似文献
13.
This paper demonstrates techniques for pre-eruption prediction of lahar-inundation zones in areas where a volcano has not
erupted within living memory and/or where baseline geological information about past lahars could be scarce or investigations
to delimit past lahars might be incomplete. A lahar source (or proximal lahar-inundation) zone is predicted based on ratio
of vertical descent to horizontal run-out of eruptive deposits that spawn lahars. Immediate post-eruption distal lahar-inundation
zones are predicted based on “pre-eruption” distal lahar-inundation zones and on spatial factors derived from a digital elevation
model. Susceptibility to distal lahar-inundation is estimated by weights-of-evidence, by logistic regression and by evidential
belief functions. Predictive techniques are applied using a geographic information system and are tested in western part of
Pinatubo volcano (Philippines). Predictive maps are compared with a forecast volcanic-hazard map through validation against
a field-based volcanic-hazard map. The predictive model of proximal lahar-inundation zone has “true positive” prediction accuracy,
“true negative” prediction accuracy, “false positive” prediction error and “false negative” prediction error that are similar
to those of the forecast volcanic-hazard map. The predictive models of distal lahar inundation zones have higher “true positive”
prediction accuracy and lower “false negative” prediction error than the forecast volcanic-hazard map, although the latter
has higher “true negative” prediction accuracy and lower “false positive” prediction error than the former. The results illustrate
utility of proposed predictive techniques in providing geo-information could be used, howbeit with caution, for planning to
mitigate potential lahar hazards well ahead of an eruption that could generate substantial source materials for lahar formation. 相似文献
14.
This paper briefly reviews the sociological literature on the “New” Chinatown phenomenon stressing its structural location
vis-à-vis the “Old” Chinatown and the homeland. It defines the New Chinatown as a panethnopolis, that is a global neighborhood
with a majority population of Chinese immigrants and of other ethnic groups of mostly Asian descent. It analyzes more particularly
the formation, development, and integration of San Francisco’s Richmond District’s New Chinatown into both the city where
it is located and the network of transglobal sites to which it belongs. It provides an interpretation of the New Chinatown
as a cultural enclave within the context of globalization theory. 相似文献
15.
The evolution of terrestrial planets (the Earth, Venus, Mars, Mercury, and Moon) was proved to have proceeded according to
similar scenarios. The primordial crusts of the Earth, Moon, and, perhaps, other terrestrial planets started to develop during
the solidification of their global magmatic “oceans”, a process that propagated from below upward due to the difference in
the adiabatic gradient and the melting point gradient. Consequently, the lowest melting components were “forced” toward the
surfaces of the planets in the process of crystallization differentiation. These primordial crusts are preserved within ancient
continents and have largely predetermined their inner structure and composition. Early tectono-magmatic activity at terrestrial
planets was related to the ascent of mantle plumes of the first generation, which consisted of mantle material depleted during
the development of the primordial crusts. Intermediate evolutionary stages of the Earth, Moon, and other terrestrial planets
were marked by an irreversible change related to the origin of the liquid essentially iron cores of these planets. This process
induced the ascent of mantle superplumes of the second generation (thermochemical), whose material was enriched in Fe, Ti,
incompatible elements, and fluid components. The heads of these superplumes spread laterally at shallower depths and triggered
significant transformations of the upper shells of the planets and the gradual replacement of their primordial crusts of continental
type by secondary basaltic crusts. The change in the character of the tectono-magmatic activity was associated with modifications
in the environment at the surface of the Earth, Mars, and Venus. The origin of thermochemical mantle plumes testifies that
the tectono-magmatic process involved then material of principally different type, which had been previously “conserved” at
deep portions of the planets. This was possible only if (1) the planetary bodies initially had a heterogeneous inner structure
(with an iron core and silicate mantle made up of chondritic material); and (2) the planetary bodies were heated from their
peripheral toward central portions due to the passage of a “thermal wave”, with the simultaneous cooling of the outer shells.
The examples of the Earth and Moon demonstrate that the passage of such a “wave” through the silicate mantles of the planets
was associated with the generation of mantle plumes of the first generation. When the “wave” reached the cores, whose composition
was close to the low-temperature Fe + FeS eutectic, these cores started to melt and gave rise to superplumes of the second
generation. The “waves” are thought to have been induced by the acceleration of the rotation of these newly formed planets
due to the decrease of their radii because of the compaction of their material. When this process was completed, the rotation
of the planets stabilized, and the planets entered their second evolutionary stage. It is demonstrated that terrestrial planets
are spontaneously evolving systems, whose evolution was accompanied by the irreversible changes in their tectono-magmatic
processes. The evolution of most of these planets (except the Earth) is now completed, so that they “dead” planetary bodies. 相似文献
16.
Piotr W. Mirowski Daniel M. Tetzlaff Roy C. Davies David S. McCormick Nneka Williams Claude Signer 《Mathematical Geosciences》2009,41(4):447-474
This research introduces a novel method to assess the validity of training images used as an input for Multipoint Geostatistics,
alternatively called Multiple Point Simulation (MPS). MPS are a family of spatial statistical interpolation algorithms that
are used to generate conditional simulations of property fields such as geological facies. They are able to honor absolute
“hard” constraints (e.g., borehole data) as well as “soft” constraints (e.g., probability fields derived from seismic data,
and rotation and scale). These algorithms require 2D or 3D training images or analogs whose textures represent a spatial arrangement
of geological properties that is presumed to be similar to that of a target volume to be modeled. To use the current generation
of MPS algorithms, statistically valid training image are required as input. In this context, “statistical validity” includes
a requirement of stationarity, so that one can derive from the training image an average template pattern. This research focuses
on a practical method to assess stationarity requirements for MPS algorithms, i.e., that statistical density or probability
distribution of the quantity shown on the image does not change spatially, and that the image shows repetitive shapes whose
orientation and scale are spatially constant. This method employs image-processing techniques based on measures of stationarity
of the category distribution, the directional (or orientation) property field and the scale property field of those images.
It was successfully tested on a set of two-dimensional images representing geological features and its predictions were compared
to actual realizations of MPS algorithms. An extension of the algorithms to 3D images is also proposed. As MPS algorithms
are being used increasingly in hydrocarbon reservoir modeling, the methods described should facilitate screening and selection
of the input training images. 相似文献
17.
Durability is one of the most important engineering properties of weak and clay-bearing rocks. Weathering can induce a rapid
change in rock material from initial properties to soil-like properties. The sensitivity of a rock type against weatherability
is usually described by a durability parameter, such as the slake durability index. However, marl resistance is not detected
satisfactorily by the durability indices by using slake durability test as suggested by ISRM for two wetting–drying cycles.
The results of this study are obtained from samples of compact or laminated eocene marls from region of Dalmatia, Croatia.
The samples were subjected to 4 cycles of slake durability, point load tests, determination of dry density, determination
of carbonate content and absorption of water. The scatter of data suggests that strength probably has no influence on the
durability of marls. On the other hand a separate group of marl samples have a second-cycle slake durability index higher
than approximately 85%, and the durability of these samples is classified as “medium-high” to “high”, although the visual
inspection of samples after testing, suggests that they should have “medium” to “low” durability classification. According
to obtained results these samples of marl fulfil the criterions for the durability classification: a carbonate content lower
than approximately 65%, a dry density lower than 2.4 Mg/m3, and values of water absorption higher than 5%. 相似文献
18.
Landslide Hazard Zonation using Remote Sensing and GIS: a case study of Dikrong river basin, Arunachal Pradesh, India 总被引：3，自引：0，他引：3
Landslides are among the most costly and damaging natural hazards in mountainous regions, triggered mainly under the influence
of earthquakes and/or rainfall. In the present study, Landslide Hazard Zonation (LHZ) of Dikrong river basin of Arunachal
Pradesh was carried out using Remote Sensing and Geographic Information System (GIS). Various thematic layers namely slope,
photo-lineament buffer, thrust buffer, relative relief map, geology and land use / land cover map were generated using remote
sensing data and GIS. The weighting-rating system based on the relative importance of various causative factors as derived
from remotely sensed data and other thematic maps were used for the LHZ. The different classes of thematic layers were assigned
the corresponding rating value as attribute information in the GIS and an “attribute map” was generated for each data layer.
Each class within a thematic layer was assigned an ordinal rating from 0 to 9. Summation of these attribute maps were then
multiplied by the corresponding weights to yield the Landslide Hazard Index (LHI) for each cell. Using trial and error method
the weight-rating values have been re-adjusted. The LHI threshold values used were: 142, 165, 189 and 216. A LHZ map was prepared
showing the five zones, namely “very low hazard”, “low hazard”, “moderate hazard”, “high hazard” and “very high hazard” by
using the “slicing” operation. 相似文献
19.
There is growing recognition among political ecologists of the need to examine shifting natural resource regimes and their
effects on livelihoods in “First World” places. This emerging literature has variously examined the “Third World within,”
the persistence of “subsistence activities” in the “First World,” and the “reterritorialization” of land tenure and access.
However, much of this work has tended to focus on traditional extractive industries in the American West, indigenous claims
to lands and resources in the U.S. and Canada, and non-timber resources on public lands. In contrast, we use a case study
of African-American sweetgrass basket-makers, associated with the Gullah culture, in South Carolina’s lowcountry to examine
the ways in which ongoing amenity-driven residential development is fundamentally reshaping resource access on private lands.
Historically, basket-makers harvested the materials (primarily sweetgrass or Mulenbergia filipes) needed for their culturally
important art form from accessible, rural, and privately held tracts of land in close proximity to their communities, but
development pressures and changes in resident interpretation of property rights has decreased access to basket-making resources.
The case is particularly illuminating, as it examines the emergence of ‘conservation subdivisions’ in the region and raises
important questions about what “rural uses” and users are being conserved through responses to exurban, suburban, and urban
development in formerly rural areas. 相似文献
20.
H. L. Vacher Larry D. Seale Lee J. Florea Robert Brinkmann 《Environmental Geology》2008,54(5):1007-1015
We apply the logic of clinical epidemiological studies to quantify the accuracy of mapping sinkholes by ALSM in the 750 km2 Pinellas County. By such studies, a new diagnostic procedure is tested by comparing the diagnoses in a clinical trial to
diagnoses on the same patients from a more reliable, but more elaborate and expensive procedure (“gold standard” in epidemiological
context). A relatively undeveloped, 65 km2 focus area where we have aerial photographs that are effectively contemporaneous with the ALSM flights serves as the “clinical
trial”. The xy-locations in the focus area are the “patients” in the trial. The “diagnostic test” for having “sinkhole disease” is inclusion
in a database of sinkhole polygons delimited by ALSM contours (“ALSM-alone”), as detailed in Part 1. The standard of comparison
(“gold standard” would be an overstatement in the absence of geophysical testing) is inclusion in a database of sinkhole outlines
derived by best judgment of conjunctive interpretation of ALSM and aerial photography. GIS intersections that indicate the
sensitivity and specificity of the test (ALSM-alone) are 43 and 98.3%, respectively, and, in the focus area where the prevalence
of “sinkhole disease” is 4.7%, the positive and negative predictive values are 55.5 and 97.2%, respectively. Over much of
the rest of the county, where only the test can be applied, the prevalence of sinkholes is sufficiently small that it cannot
be determined to be any different from zero given the paucity of interpreted sinkholes (positive diagnoses) and the low specificity
of the test method. The conclusion, therefore, is that contemporaneous aerial photography is essential to compile an ALSM-derived
database that aims to state that the given xy-points lay inside or outside of topographic depressions in the covered karst of west-central Florida. 相似文献