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1.
In the northern uplands of the Socialist Republic of Vietnam the state is taking dramatic steps to (re)configure agricultural production through the introduction and subsidisation of hybrid rice and maize seeds. These require yearly cash investments and access to state supplied inputs, a far cry from earlier upland ethnic minority livelihood strategies. In this paper we develop a conceptual framework that brings together an actor-oriented livelihoods approach with concepts from everyday politics and resistance, to examine the relations now at play as ethnic minorities, namely Hmong and Yao households in Lào Cai province, react to the introduction of these hybrid seeds, negotiate with the state over their use, and contest and subtly resist the wholesale adoption of this programme. Our framework takes us beyond an investigation into financial benefits and yields, to focus upon the social, cultural and political aspects inherent in upland farmer decision-making regarding state interventions. Our findings reveal that such agricultural programmes have resulted in new food insecurities and vulnerabilities overlaying more established concerns. Yet in turn, ethnic minority households evaluate these innovations according to their own terms, and have responded by negotiating, accommodating, and also contesting the state’s initiatives using creative and innovative everyday politics and livelihood strategies. In so doing, they have worked to maintain autonomy over choices and decision-making vis-à-vis the economic, social and cultural reproduction of their household units; a delicate balancing act in a socialist state. 相似文献
2.
《Geoforum》2016
Agricultural intensification is at the core of the current agrarian transition in Southeast Asia. New crop varieties promise higher productive outputs, but depend on significant increases in chemical inputs. In the highlands of northern Vietnam, we find that adopting hybrid maize is inevitably associated with an increasing dependence on cash for direct and indirect inputs and investments. This reliance on the cash economy is a new reality for semi-subsistence ethnic minority Hmong households, and provides evidence of the advancing agrarian transition in Vietnam’s remote northern highlands. While livelihood outcomes of hybrid seed adoption include increased maize yields, local farmers highlight numerous drawbacks, including unstable input prices, limited storage periods, pest concerns, and the increased reliance on cash. Strong preferences for the taste of traditional local maize, as well as concerns over regular harvests, lead many households to resist the full adoption of new hybrid varieties and redirect hybrid maize to livestock feed and household alcohol production instead. Thus while state policies extoll the virtues of high-yielding hybrid maize for poverty reduction, we find that food availability is an overemphasized element of household food security and upland agricultural development policies. Food security interventions must move beyond conceptualizing food security as a result of food availability alone, and also incorporate cultural acceptability of food, better understandings of hybrid maize cultivation challenges, and respect the seed diversity on which local livelihoods and food security rely. 相似文献
3.
Jeremy Crampton 《GeoJournal》1996,39(4):353-361
This paper begins by first giving a critique of the conflict in Bosnia from a geographical and cartographic perspective; and in particular how plans to address and solve the crisis have revolved around the cartographic delineation of territory. This is in effect a process of ‘bordering’ on Bosnia. What are the consequences of using maps to partition multi-ethnic states by constructing regions of ethnic dominance? What alternative territorial divisions might be available which are more sensitive to local use of resources? Second, the paper examines the details of the Dayton plan and argues that it is just the latest of a series of plans for Bosnia which defeat the ideal of pluralism. When the ideal of pluralism is dead, then the necessity of living together dies also. What results is not a desired Bosnia, but a divided Bosnia; one only ‘bordering’ on Bosnia in a kind of quasi- or unreal state. Throughout the paper the focus is on the role that maps have played in the conflict, how they have been contested and how they have been used to support the various interests of the parties involved. 相似文献
4.
谢良珍 《沉积与特提斯地质》1988,8(Z1):69-80
《中国古地理图集》(下面简称《图集》)属於概略性古地理图,是一本八开本的综合性图集,由多种专业类型的全国性图件和地区性图件123幅及20万文字说明和英文摘要组成。《图集》从设计、编绘、制版、印刷历时数年,经地质人员、制图人员、制印人员、出版工作者等多方通力协作,现已正式出版发行。本文希望通过总结与探讨《图集》制图设计与编制工作中的某些有关问题,能有助于小比例尺大区域岩相古地理图的编制工作。 相似文献
5.
An understanding of what influences sinkhole formation and the ability to accurately predict sinkhole hazards is critical
to environmental management efforts in the karst lands of southeastern Minnesota. Based on the distribution of distances to
the nearest sinkhole, sinkhole density, bedrock geology and depth to bedrock in southeastern Minnesota and northwestern Iowa,
a decision tree model has been developed to construct maps of sinkhole probability in Minnesota. The decision tree model was
converted as cartographic models and implemented in ArcGIS to create a preliminary sinkhole probability map in Goodhue, Wabasha,
Olmsted, Fillmore, and Mower Counties. This model quantifies bedrock geology, depth to bedrock, sinkhole density, and neighborhood
effects in southeastern Minnesota but excludes potential controlling factors such as structural control, topographic settings,
human activities and land-use. The sinkhole probability map needs to be verified and updated as more sinkholes are mapped
and more information about sinkhole formation is obtained. 相似文献
6.
Alan Yong Susan E. Hough Michael J. Abrams Christopher J. Wills 《Journal of Earth System Science》2008,117(2):797
Estimation of the degree of local seismic wave amplification (site effects) requires precise information about the local site conditions. In many regions of the world, local geologic information is either sparse or is not readily available. Because of this, seismic hazard maps for countries such as Mozambique, Pakistan and Turkey are developed without consideration of site factors and, therefore, do not provide a complete assessment of future hazards. Where local geologic information is available, details on the traditional maps often lack the precision (better than 1:10,000 scale) or the level of information required for modern seismic microzonation requirements. We use high-resolution (1:50,000) satellite imagery and newly developed image analysis methods to begin addressing this problem. Our imagery, consisting of optical data and digital elevation models (DEMs), is recorded from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) sensor system. We apply a semi-automated, object-oriented, multi-resolution feature segmentation method to identify and extract local terrain features. Then we classify the terrain types into mountain, piedmont and basin units using geomorphometry (topographic slope) as our parameter. Next, on the basis of the site classification schemes from the Wills and Silva (1998) study and the Wills et al (2000) and Wills and Clahan (2006) maps of California, we assign the local terrain units with V s 30 (the average seismic shear-wave velocity through the upper 30m of the subsurface) ranges for selected regions in Mozambique, Pakistan and Turkey. We find that the applicability of our site class assignments in each region is a good first-approximation for quantifying local site conditions and that additional work, such as the verification of the terrain’s compositional rigidity, is needed. 相似文献
7.
Flood basalts represent large outpourings of lavas which often cover, and interact with, sedimentary basins. For this reason areas with significant flood basalt cover are often targets for hydrocarbon exploration. Problems exist, however, when trying to image sediments and structures in offshore regions covered by basalts. Here we present preliminary 3-D models of the Etendeka flood basalt province from NW Namibia, which can act as an aid in understanding the internal and external architecture of the flood basalt cover. Satellite images, digital elevation models, measured geological logs, sections and maps, are used to create the geological model. Models are presented in 2 parts; 1) models created using topography with images such as Land Sat and geological maps draped over them, and 2) a 3-D model of key lava and sediment surfaces in the basin as defined by measured geological sections. Initial results show a palaeo-volcanic feature early in the flood basalt history which is onlapped by later Iavas. The modelling also allows a simple correction for post emplacement subsidence by assuming an original sub horizontal position for the first basin wide silicic flow unit. 相似文献
8.
This paper considers some significant questions in geography and cognate fields about the roles of maps in the information age. Most maps are now digital products, offering immersive environments for user involvement. The increasingly networked digital distribution of geographic information in consumer-orientated cartographic representations leads to substantial changes how people individually and collaboratively experience and produce space and place. This article focuses on the ongoing metamorphosis arising through geobrowsing, the media-based flexible production of geographic knowledge through interactive maps. Drawing on work in media studies influenced by the so-called spatial turn—the rediscovering of geography-related questions in the social sciences and humanities, after modernism’s claimed prioritization of time and history (Soja in Postmodern Geographies. The reassertion of space in critical social theory, London, 1989; Jameson in Postmodernism, or, the cultural logic of late capitalism, Duke University Press, Durham, 1991)—this paper develops a theoretical framework built on the dynamic networked geomedial action spaces concept to understand the changing roles of information age maps as imagined materialist spaces for the experience and production of space—ultimately a medial turn. Following this concept, maps change from offering static and non-interactive frames of geographic reference for the production of space and place and as geomedia support a veritable infinity of interactive and map-based activities. Geobrowsing facilitates some new modes of geographic interactions that move from logocentric engagements with static maps to egocentric dynamic interactions with code-based elements of geomedial action spaces. Google Earth and similar geomedia facilitate maps that become intrinsic to a growing number of social action spaces and alter the experience and production of space and place. 相似文献
9.
H. B. Havenith I. Torgoev A. Meleshko Y. Alioshin A. Torgoev G. Danneels 《Landslides》2006,3(2):137-147
Mailuu-Suu is a former uranium mining area in Kyrgyzstan (Central Asia) at the northern border of the Fergana Basin. This region is particularly prone to landslide hazards and, during the last 50 years, has experienced severe landslide disasters in the vicinity of numerous nuclear waste tailing dams. Due to its critical situation, the Mailuu-Suu region was and still is the target area for several risk assessment projects. This paper provides a brief review of previous studies, past landslide events and a discussion on possible future risk scenarios. Various aspects of landslide hazard and related impacts in the Mailuu-Suu Valley are analyzed in detail: landslide susceptibility, historical evolution of landslide activity, size-frequency relationship, river damming and flooding as well as impacts on inhabited areas and nuclear waste storage zones. The study was carried out with standard remote sensing tools for the processing of satellite imagery and the construction of digital elevation models (DEMs). The processed inputs were combined on a GIS platform with digital landslide distribution maps of 1962, 1977, and 2003, digitized geological and geographic maps, and information from landslide monitoring and geophysical investigation.As a result, various types of landslide susceptibility maps based on conditional analysis (CA) are presented as well as predictions of future landslide activity and related damming potential and their possible impact on the population. For some risk scenarios, remediation and prevention measures are suggested. 相似文献
10.
Tingting Yao Craig Calvert Tom Jones Glen Bishop Yuan Ma Lincoln Foreman 《Mathematical Geology》2006,38(1):51-62
Spectral simulation has gained application in building geologic models due to the advantage of better honoring the spatial continuity of petrophysical properties, such as reservoir porosity and shale volume. Distinct from sequential simulation methods, spectral simulation is a global algorithm in the sense that a global density spectrum is calculated once and the inverse Fourier transform is performed on the Fourier coefficient also only once to generate a simulation realization. The generated realizations honor the spatial continuity structure globally over the whole field instead of only within a search neighborhood, as with sequential simulation algorithms. However, the disadvantage of global spectral simulation is that it traditionally cannot account for the local information such as the local continuity trends, which are often observed in reservoirs and hence are important to be accounted for in geologic models. This disadvantage has limited wider application of spectral simulation in building geologic models. In this paper, we present ways of conditioning geologic models to the relevant local information. To account for the local continuity trends, we first scale different frequency components of the original model with local-amplitude spectrum ratios that are specific to the local trend. The sum of these scaled frequency components renders a new model that displays the desired local continuity trend. The implementation details of this new method are discussed and examples are provided to illustrate the algorithm. 相似文献
11.
Landslide susceptibility analysis in the Hoa Binh province of Vietnam using statistical index and logistic regression 总被引：12，自引：2，他引：10
The purpose of this study is to evaluate and compare the results of applying the statistical index and the logistic regression
methods for estimating landslide susceptibility in the Hoa Binh province of Vietnam. In order to do this, first, a landslide
inventory map was constructed mainly based on investigated landslide locations from three projects conducted over the last
10 years. In addition, some recent landslide locations were identified from SPOT satellite images, fieldwork, and literature.
Secondly, ten influencing factors for landslide occurrence were utilized. The slope gradient map, the slope curvature map,
and the slope aspect map were derived from a digital elevation model (DEM) with resolution 20 × 20 m. The DEM was generated
from topographic maps at a scale of 1:25,000. The lithology map and the distance to faults map were extracted from Geological
and Mineral Resources maps. The soil type and the land use maps were extracted from National Pedology maps and National Land
Use Status maps, respectively. Distance to rivers and distance to roads were computed based on river and road networks from
topographic maps. In addition, a rainfall map was included in the models. Actual landslide locations were used to verify and
to compare the results of landslide susceptibility maps. The accuracy of the results was evaluated by ROC analysis. The area
under the curve (AUC) for the statistical index model was 0.946 and for the logistic regression model, 0.950, indicating an
almost equal predicting capacity. 相似文献
12.
Analysis of landslide susceptibility in the Suusamyr region, Tien Shan: statistical and geotechnical approach 总被引：2，自引：0，他引：2
The Suusamyr region is located in the northern part of the Tien Shan Range in Central Asia. In 1992, this region was hit by
the Ms = 7.3 Suusamyr earthquake triggering several large landslides along the Suusamyr Valley and on the southern slopes
of the adjacent Suusamyr Range. One of these landslides had been investigated by geophysical and geotechnical methods in order
to determine local trigger factors. The present paper focuses on the influence of geological and morphological factors upon
landslide occurrence on a regional scale. The analysis is based on a digital data set including landslides triggered in 1992
and several older landslides as well as various types of digital elevation models (DEMs), ASTER image data, and geological
and active fault maps. These data were combined to compute landslide susceptibility (LS) maps using statistical methods, Landslide
Factor and Conditional Analyses (LFA, CA), as well as a geotechnical one, the Newmark's Method (NM). The landslide data set
was also analyzed with respect to the size–frequency relationship.
An erratum to this article can be found at 相似文献
13.
Ethnic Enclave Reconfiguration: A ‘new’ Chinatown in the Making 总被引：1，自引：0，他引：1
Years of past research on traditional Chinatowns were based on the assumption that Chinatown is an ethnic enclave for a single
ethnic minority, i.e. the Chinese. In recent years, one could observe significant changes over Chinatowns in terms of more
Vietnamese presence. Yet, the transition process as an object of study is much under-represented in the literature on ethnic
enclaves. Looking at ethnic business transition from Hong Kong to Vietnamese in Toronto’s Chinatown West, this paper argues
strongly that ‘multiple ethnicity’ can coexist in an enclave. For this case study, the Chinatown is being reconfigured into a ‘new’ Chinatown. Drawing upon data from the authors’ Vietnamese Business Database that covers information between
1983 and 2003, we present both spatial and temporal analyses that offer insights into how the Vietnamese businesses grow through
time. Our findings support the existence of a Vietnamization process in Toronto Chinatown West. However, its evolution is
still in an infant stage. In some aspects, the incoming Vietnamese businesses display similarities with the remaining Hong
Kong businesses. In sum, a total reconfiguration of Chinatown West in form and business nature is still unaccomplished. The
conventional enclave concept which bases on the singularity of ethnic group has to be abandoned in view of rising occurrence
of ethnic transition, particularly in this globalizing era. 相似文献
14.
总结应用VirtuoZo NT、JX4C DPW全数字摄影测量系统(DPS)制作数字高程模型(DEM)和数字正射影像图(DOM)的经验,论述DEM和DOM生产过程主体技术线路及存在的主要技术问题,分析如何提高DEM和DOM的精度方法,阐述DEM和DOM的质量控制环节,探讨特性划分评价方法。 相似文献
15.
Monica Stephens 《GeoJournal》2013,78(6):981-996
The GeoWeb presents an opportunity to expand the array of potential contributors describing the earth through digital geographic information. However, the adoption of user-generated geographic information has not been uniform, resulting in an uneven distribution of content and more nuanced digital divides. This paper uses a survey of Internet users to measure the gender divide in the contributions of cartographic information to the Internet and examine the impact of this divide within the context of OpenStreetMap and Google MapMaker. This paper argues that in both publicly available basemaps the gender divide results in men serving as the gatekeepers of local knowledge leading to gendered user-generated representations. As these digital basemaps are reproduced and utilized by almost every mobile application or web-based map, the gender divisions in the creators and content are endlessly reproduced. 相似文献
16.
Educational tsunami evacuation map brochures in Washington and Oregon have been developed locally, resulting in significant
differences between the types of tsunami hazard information they include. This paper identifies six tsunami hazard information
types present in 38 brochures in Washington and Oregon: (1) tsunami hazard zone, (2) road network, (3) assembly areas, (4)
evacuation guidance, (5) infrastructure, and (6) terrain. It compares and contrasts these information types in the maps and
text of six of the brochures, including a proposed design standard in Oregon. Design differences of all 38 brochure maps are
then organized using principles of cartographic abstraction, which describe mapmaker decisions about selection, generalization,
and symbolization of information. We further use this framework to situate the information content of a new interactive Google
Maps tool in Oregon. Our assessment identifies limitations of current tsunami hazard information that may be relevant to improving
tsunami education. In theory, more advanced evacuation map tools can play an important role in reducing the limitations of
tsunami hazard information relevant to the public. The new Google Maps tool addresses few of these limitations. Recognizing
how map-making decisions define the underlying information content of evacuation maps can facilitate much needed future evaluations
and developments in evacuation map design. 相似文献
17.
Accuracy assessment of InSAR derived input maps for landslide susceptibility analysis: a case study from the Swiss Alps 总被引：2，自引：0，他引：2
In recent years SAR interferometry has become a widely used technique for measuring altitude and displacement of the surface
of the earth. Both these capabilities are highly relevant for landslide susceptibility studies. Although there are many problems
that make the use of SAR interferometry less suitable for landslide inventory mapping, it’s use in landslide monitoring and
in the generation of input maps for landslide susceptibility assessment looks very promising. The present work attempts to
evaluate the usefulness and limitations of this technique based on a case study in the Swiss Alps. Input maps were generated
from ERS repeat pass data using SAR interferometry. A land cover map has been generated by image classification of multi-temporal
SAR intensity images. An InSAR DEM was generated and a number of maps were derived from it, such as slope-, aspect, altitude-
and slope form classes. These maps were used to generate landslide and rockfall susceptibility maps, which give fairly well
acceptable results. However, a comparison of the InSAR DEM with the conventional Swisstopo DEM, indicated significant errors
in the absolute height and slope angles derived from InSAR, especially along the ridges and in the valleys. These errors are
caused by low coherence mostly due to layover and shadow effects. Visual comparison of stereo images created from hillshading
maps and corresponding DEMs demonstrate that a considerable amount of topographic details have been lost in the InSAR-derived
DEM. It is concluded that InSAR derived input maps are not ideal for landslide susceptibility assessment, but could be used
if more accurate data is lacking. 相似文献
18.
B. Meissner 《GeoJournal》1994,32(1):71-79
It is the aim of the author to show the general geo-scientific audience how they can profit from the specific view of cartographers when using remote sensing data. Leading from the explanation of cartography's tasks and the technically unique cartographic view on remote sensing data, it links up to the cartographic use of the data material. The author describes the direct and indirect applications with regard to topographic and thematic maps and reports from various practical projects in order to illustrate the main points. Finally the future dimension of remote sensing cartography within the field of developing geographical information systems (GIS) is pointed out. 相似文献
19.
Geostatistics provides a suite of methods, summarized as kriging, to analyze a finite data set to describe a continuous property of the Earth. Kriging methods consist of moving window optimum estimation techniques, which are based on a least-squares principle and use a spatial structure function, usually the variogram. Applications of kriging techniques have become increasingly wide-spread, with ordinary kriging and universal kriging being the most popular ones. The dependence of the final map or model on the input, however, is not generally understood. Herein we demonstrate how changes in the kriging parameters and the neighborhood search affect the cartographic result. Principles are illustrated through a glaciological study. The objective is to map ice thickness and subglacial topography of Storglaciären, Kebnekaise Massif, northern Sweden, from several sets of radio-echo soundings and hot water drillings. New maps are presented. 相似文献
20.
Geostatistics provides a suite of methods, summarized as kriging, to analyze a finite data set to describe a continuous property of the Earth. Kriging methods consist of moving window optimum estimation techniques, which are based on a least-squares principle and use a spatial structure function, usually the variogram. Applications of kriging techniques have become increasingly wide-spread, with ordinary kriging and universal kriging being the most popular ones. The dependence of the final map or model on the input, however, is not generally understood. Herein we demonstrate how changes in the kriging parameters and the neighborhood search affect the cartographic result. Principles are illustrated through a glaciological study. The objective is to map ice thickness and subglacial topography of Storglaciären, Kebnekaise Massif, northern Sweden, from several sets of radio-echo soundings and hot water drillings. New maps are presented. 相似文献