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1.
Roads have manifold social and environmental impacts, including regional development, social conflicts and habitat fragmentation. ‘Road ecology’ has emerged as an approach to evaluate the various ecological and hydrological impacts of roads. This article aims to complement road ecology by examining the socio‐spatial processes of road building itself. Focusing on the Brazilian Amazon, a heavily‐studied context due to forest fragmentation by roads, the authors consider non‐state social actors who build ‘unofficial roads’ for the purpose of gaining access to natural resources to support livelihoods and community development. They examine four case studies of roads with distinct histories in order to explain the socio‐spatial processes behind road building in terms of profit maximization, land tenure claims, co‐operative and conflictive political ecologies, and constraints as well as opportunities afforded by the biophysical environment. The study cases illustrate the need for a multi‐pronged theoretical approach to understanding road building, and call for more attention to the role of non‐state actors in road construction.  相似文献   

2.
Abstract

Monitoring and understanding of land use/forest cover dynamics as well as the factors affecting the changes in land use/forest cover are necessary for the sustainable management of natural resources. This study analyzes the spatial and temporal changes in land use and forest cover patterns in a typical mountain forest area in the Torul State Forest Enterprise area of Northeastern Turkey. The investigation evaluates the temporal changes of the spatial structure of forest conditions through the spatial analysis of forest-cover type maps from 1984 and 2005 using GIS and FRAGSTATS. The evidence presented here showed that there were drastic changes in the temporal and spatial dynamics of land use/forest cover, and between 1984 and 2005 there was a net increase of 19.9% in total forested area. Productive forest area increased by 3161 ha, although degraded forest area increased 9216 ha. In examining the changes of crown closure and development stages of the forest ecosystem during the study period, the forest stand area with low crown closures increased. The regenerated area increased because of regeneration activities while the other development stages were left to grow to older development stages in the period. These results regarding the crown closure and development stage show that forest quality has increased, and this is partly due to emigration of the rural population in Torul. In terms of spatial configuration, the landscape structure in Torul, the State Forest Enterprise area, changed substantially over the 21-year study period, resulting in fragmentation of the landscape as indicated by large patch numbers and smaller mean patch sizes, owing to heavy timber subtraction, illegal cutting, and uncontrolled stand treatments.  相似文献   

3.
Parks Canada began the Northern Satellite Monitoring Program in 1997, with the objective of tracking large‐scale vegetation variation in Canadian ecosystems and helping land managers to develop appropriate management practices in response to climate change. Under this program, a sequence of 10‐day composite Advanced Very High Resolution Radiometer (AVHRR)‐derived Normalized Difference Vegetation Index (NDVI) data from 1985 to 2007 was examined to study seasonal and inter‐annual relationships between vegetation and climate data over Canadian ecosystems using statistical and wavelet analysis. Statistical analysis showed that temperature was the principal driver for seasonal variability in greenness, explaining more than 70 percent of seasonal variation in vegetation for most Canadian ecozones. In comparison with temperature, the relationships between NDVI and precipitation were weaker but still significant. Maximum annual NDVI showed increasing trends in Canadian ecozones during the study period, although increasing rates were spatially heterogeneous. Wavelet analysis confirmed that inter‐annual variation in NDVI was different at two ecozones in Canada. NDVI variation in the Northern Arctic was significant at scales of 3–4 years from 1997 to 2001, which was associated with temperature and precipitation variation. Comparatively, NDVI variation in the Boreal Shield was significant at scales of 5–8 years from 1991 to 1999, but did not correspond with climate variation.  相似文献   

4.
For over a decade the Science Council of Canada has argued with increasing conviction that Canada's industrial dilemmas stem from technological weaknesses that result primarily from high levels of foreign ownership (e.g. Cordell, 1971; Bourgault, 1972; Britton and Gilmour, 1978; Shepherd, 1980). Indeed, the council urges that only by adopting an industrial strategy explicitly based on the concept of technological sovereignty can Canada hope to ensure the international competitiveness of its economy and offer the employment opportunities appropriate to its stage of development. If such pleas are to be translated into comprehensive and coherent action, however, there is an admitted need for more sectoral studies to detail the effects of foreign ownership and provide an evaluation of existing capacilities necessary to the formulation of effective policies. In this paper, therefore, I will briefly compare research and development (r & d) in the forest product sectors of Canada and the United States. Since Canada's forest industries have long attracted foreign, and especially American, direct investments, such a comparison is considered to be particularly appropriate (Marshall et al., 1936: 35–55; Hayter, 1981a).  相似文献   

5.
Pre-Hispanic mounds, known as “cerritos,” “cerritos de indios,” or “aterros” across southeastern South America, are one of the most conspicuous and well-studied cultural manifestations in lowlands archaeology. Nevertheless, in the Upper Delta of the Paraná River, mounds are rarely studied, and even their anthropic origin is under debate. This could be related to the fact that anthropogenic mounds are located on a floodplain where other “mound-like” natural geoforms (generated by fluvial processes) are also present. In addition to this, the natural geoforms also contain evidence of Holocene human occupation (sherds, bones, charcoal, humans burials, etc.), which can lead to interpretive errors of their origin and formation. Thus, this project set out to determine the genesis and evolution of these mounds and also to identify the cultural occupation and transformation of natural landforms found in the area. In this article, natural and anthropogenic systems and processes were identified and characterized through the application of proxy record analysis (i.e., sediment composition, stratigraphy, micromorphology, silica bodies and chronological analysis) at the Los Tres Cerros archaeological locality in the Upper Delta of the Paraná River of Victoria County, Entre Ríos Province, Argentina. This analysis allowed for the recognition of natural anthropogenic interfaces, such as the “pre-mound” occupation as well as evidence of cultural activities such as mound construction, between 1,000 and 500 14C years bp. These findings were integrated into current research on the variability of mound construction during the Late Holocene in the lowlands of South America.  相似文献   

6.
Palynological researches have been carried out in the framework of cooperative projects with local and national institutions at the Villa Romana del Casale of Piazza Armerina, a small town in central Sicily. The site was studied within a multidisciplinary geo-bio-archaeological set of studies aiming at understanding the economy and environment at a local scale. Analyses allowed us to reconstruct the natural vs cultural landscape dynamics from Roman to medieval periods. On the basis of 85 samples, pollen diagrams show that the site has been built in a low forest cover area, with signs of both natural/semi-natural cover and complex anthropogenic activities. These activities include cereal fields and pastures. There is evidence of ornamental (e.g. Platanus, Buxus) and fruit trees (above all Olea, and also, e.g. Corylus, Prunus and Juglans). The research also includes a detailed study about the finding of Vitis pollen grains in the Roman site. In the subsequent phases, pollen shows again an open, fairly treeless, landscape with Mediterranean and hilly vegetation. Anthropogenic signs are evident in the form of groves and orchards. Our data bring evidence and details about the intense land exploitation that had contributed to transform the environment of central Sicily during the Middle and Late Holocene. Data demonstrate that archaeopalynology may be fruitfully regarded as a tool to understand the current landscape structure.  相似文献   

7.
ABSTRACT Every nation, formally or informally, defines and establishes the lines of political and fiscal authority among its national, regional, and local governments. Historically, centralized governments tend to restrict the power and autonomy of provincial and local governments. In this paper, we exploit the quasi‐experimental distribution of political institutions in the Americas caused by variation in European colonial experience to examine the impact of institutions on urban and local development, specifically on the degree of urban primacy, the size distribution of cities, the number and density of local government units, and the fragmentation of metropolitan areas. We argue that centralization of political power at the national level, as experienced in many countries in Latin America, contributes to urban primacy and a size distribution of cities favoring large cities. Additionally, even in more politically decentralized countries such as Canada and the U.S., variance in political centralization at the provincial (state) level over local governments led to significant divergences in urban primacy, the distribution of city sizes, as well as the form, number, and density of local governments. While we cannot rule out the importance of other factors, our findings suggest that political centralization affects spatial economic development.  相似文献   

8.
High Occupancy Toll (HOT) lanes that use dynamic pricing to manage congestion and generate revenue are increasingly popular. In this paper, we estimate the behavioral response of drivers to dynamic pricing in an HOT lane. The challenge in estimation lies in the simultaneity of price and demand: the structure of dynamic tolling ensures that prices increase as more drivers enter the HOT lane. Prior research has found that higher prices in HOT lanes increase usage. We find that after controlling for simultaneity HOT drivers instead respond to tolls in a manner consistent with economic theory. The average response to a 10 percent increase in the toll is a 1.6 percent reduction in usage. Drivers primarily value travel reliability over time savings, although there is heterogeneity in the relative values of time and reliability based on time of day and destination to or from work. The results highlight the importance of both controlling for simultaneity when estimating demand for dynamically priced toll roads and treating HOT lanes with dynamic prices as a differentiated product with bundled attributes.  相似文献   

9.
The rock‐cut tomb of Bolores in the Portuguese Estremadura dates primarily to the Late Neolithic/Copper Age (2800–2600 BC) and, in a series of recent excavations, has yielded thousands of fragmented, commingled human bone specimens. The primary goals of the present study were to determine the minimum number of individuals interred in the tomb and to analyse spatial patterns in fragmentation intensity to identify natural and anthropogenic taphonomic processes. To investigate these research questions, the authors employed a simplified version of an established method in zooarchaeology to the study of human remains. Human bone specimens were recorded by the presence of osteological landmarks rather than the zones used in similar studies. This recording system allowed for calculation of the minimum number of individuals (further refined through dental analysis) and generated the NISPs (Numbers of Identified Specimens), minimum number of elements, fragment counts and landmarks sums essential to the conjoining and fragmentation studies. Fragmentation analysis led to the identification of four possible use areas in the tomb: two for primary inhumations and two for secondary deposits created by cleaning out the burial chambers at Bolores. We found that the application of multiple zooarchaeological methods to the study of commingled human remains has the potential to provide a more fine‐grained understanding of site biography and taphonomy than human osteological methods alone. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

10.
This article aims at assessing the diversity of regional innovation systems and their economic performance in Europe. We propose to adapt the social systems of innovation and production (SSIP) framework at the regional level by identifying the specific arrangements of each part of the innovation and production system. Three key features of European regions are investigated using this framework: the diversity of regional SSIP, the interplay of regional and national determinants of such systems, and the impact of SSIP on regional performance. We identify a typology of regional configurations resulting from the combination of scientific, technological, educational and industrial indicators, using multivariate data analysis. A variance analysis approach is then developed in order to test the existence of specific regional growth regimes. The results highlight a persistently high level of diversity of regional configurations, notably among knowledge intensive regions, but also show that national institutional settings remain of fundamental importance in shaping a number of regional configurations. A final conclusion relates to the weak correlation observed between the structural characteristics of regions and their performance over the 2003–2007 period: regional performance remains primarily shaped by national trends. Overall, the paper questions the regional dimension of these “systems”.  相似文献   

11.
Abstract. Nations and national projects are gendered in different ways. Feminist theory has raised important questions about the conceptualisation of ‘difference’. This article develops the conceptualisation of the different ways in which nations and national projects are gendered, arguing for a mid‐level conceptualisation of gender relations. It argues against, on the one hand, the excessive fragmentation of gender, and on the other, too simple dichotomies of mordless unequal gender relations. This draws on a theorisation of gender relations which connects the different dimensions into specific kinds of gender regimes, either public or domestic gender regimes. This enables us to conceptualise different national projects as having a more or less public or domestic gender project. The conflicts between different national projects and with other polities, such as states, are then conflicts between differently gendered projects. The usefulness of this mid‐level conceptualisation is demonstrated through examples of the competing relations between the UK, Ireland, the EU and the Catholic Church in a global era.  相似文献   

12.
This article introduces a novel concept, humanitarian security regimes, and enquires under what conditions they arise and what is distinctive about them. Humanitarian security regimes are driven by altruistic imperatives aiming to prohibit and restrict behaviour, impede lethal technology or ban categories of weapons through disarmament treaties; they embrace humanitarian perspectives that seek to prevent civilian casualties, precluding harmful behavior, protecting and ensuring the rights of victims and survivors of armed violence. The article explores how these regimes appear in the security area, usually in opposition to the aspirations of the most powerful states. The existing regimes literature has mostly taken a functional approach to analyzing cooperation, lacks a humanitarian hypothesis and does not explore the emergence of new regimes in the core area of security. The author argues that in the processes of humanitarian security regime‐making, it is the national interest that is restructured to incorporate new normative understandings that then become part of the new national security aspirations. This article intends to fill this gap and its importance rests on three reasons. First, security areas that were previously considered to be the exclusive domain of states have now been the focus of change by actors beyond the state. Second, states have embraced changes to domains close to their national security (e.g. arms) mostly cognizant of humanitarian concerns. Third, states are compelled to re‐evaluate their national interests motivated by a clear humanitarian impetus. Three conditions for the emergence of humanitarian security regimes are explained: marginalization and delegitimization; multilevel agency, and reputational concerns.  相似文献   

13.
Transformation of forest policy regimes in Finland since the 19th century   总被引:1,自引:0,他引:1  
In this paper, interpretations of sustainable forestry are investigated against the historical background of transformations in the industrial utilisation of forests. Three distinct forest policy regimes in Finland since the 19th century are identified. First, the introduction of the German forestry model, with the central notion of sustained yield, and the establishment of the Finnish Forest Service took place simultaneously in the latter half of the 19th century. These actions aimed at changing patterns of local forest use considered detrimental to long-term forest utilisation. Second, a national forest sector was established during the 20th century. Industrial forestry was seen as a guarantee of economic independence for the new nation-state. Third, during a recent phase the influence of non-governmental organisations and international forest industry companies has increased, and traditional power relations have changed as issues such as biodiversity, forest certification and global investments have been introduced to the debates. It is concluded that the recent transformations in forest management should be read as transformations in industrial forestry rather than as abandonment of industrial forest use models; the legacy of the 19th century German forest science still prevails in forest management.  相似文献   

14.
Saharan dust: sources and trajectories   总被引:1,自引:0,他引:1  
The Sahara is the world's largest source of aeolian desert dust, but precise information on specific sources of this material is poor and sometimes contradictory. This paper uses daily data from the Total Ozone Mapping Spectrometer (TOMS) for 1999 to identify source areas for major dust events and their trajectories of long-range transport. Two major source areas are identified: the Bodélé depression and an area covering eastern Mauritania, western Mali and southern Algeria. Both of these major dust sources are primarily driven by natural factors since they are little affected by anthropogenic activities.  相似文献   

15.
Pollen, non-pollen palynomorphs and charcoal from a colluvial soil surrounded by prehistoric petroglyphs (Campo Lameiro, NW Spain) were studied in order to assess the nature of human activities and their impact on Holocene vegetation patterns. Several phases of anthropogenic impact were observed. (i) Between 7.6 and 6.5 ka cal BP, synanthropic taxa (Urtica dioica type, Plantago lanceolata type) and coprophilous fungi (e.g. Sporormiella-type) are indicative of early (pre-agricultural) creation of small patches of pasture using fire, possibly for incipient animal husbandry or as part of a deliberate strategy to improve game availability. Such activities only had a minor effect on the deciduous Quercus-dominated forest established earlier during the Holocene Thermal Maximum. (ii) Between 5.9 and 4.8 ka cal BP a more intense signal indicative of pastoral activity was detected, corresponding to the Neolithic period. (iii) Between 4.8 and 3.4 ka cal BP, which fits within the hypothetical timeframe of petroglyph creation, the synanthropic and humidity (e.g. Cyperaceae, Mougeotia) indicators diminished while charcoal concentration increased, which can be explained by Mid-Holocene cooling/drying (Neoglaciation) in combination with reduced human impact, or by non-pastoral activities in the area possibly in association with the development of the rock art culture, converting pasture to protected open ground through anthropogenic fires. (iv) During the Late Bronze Age and Early Iron Age (3.4–2.5 ka cal BP), grazing pressure and fire regime intensity are high, coinciding with evidence of regional forest regression, despite an amelioration in climate. (v) Later phases, not corresponding to prehistoric rock art contexts, include a phase of heavy grazing and reduced fire frequency (from ca. 2.5 to 1.2 ka cal BP) as well as the near complete elimination of the deciduous woodland, the expansion of ericaceous shrubland and the evidence of local agriculture and afforestation. These results are consistent with earlier studies in the area and highlight the spatial heterogeneity in the vegetation especially during periods of prehistoric anthropogenic interference.  相似文献   

16.
Since Mexican geography was initiated, its practice has been closely related to the objectives and activities of the hegemonic regimes and ruling activities within the territory. A short passage through our history might clarify why we have not been able to avoid conservatism, illustrate how cultural geography has developed in recent years, and explain why Mexican geographers are so dependent on theory from abroad. Historically, just like in other territories, mapping and teaching were the main practices developed with different targets and different contexts, in the evolution of the country. Since colonization in the sixteenth and seventeenth centuries, new discoveries and the display of new natural resources has demanded the knowledge and register of new places, especially on maps. This activity was primarily undertaken by foreigners: the Spaniards colonized and conquered new spaces and resources, seizing and exporting minerals like gold and silver, tropical products such as sugar cane, coffee and cacao, and animals such as the beaver (Wolf 1994).  相似文献   

17.
ABSTRACT

This article explores the geographies of education at the National Museum of Canada in the first half of the twentieth century. Through an analysis of the spatialization of children’s museum education, we highlight how the museum sought to inculcate in young Canadians knowledges about their country, its people, and natural resources. We situate children’s museum education within the broader context of Canadian nationalism, other museum activities, and public education in the capital. Focusing on the design and material organization of the museum, we highlight how the space of the museum, from the objects on display to the imposing grandeur of the building, sought to impress upon students the importance of the knowledge it conveyed. Finally, we illustrate how the museum’s programming aimed to provide children with knowledge of their national heritage, building citizenship through claims of development as destiny.  相似文献   

18.
Although archaeological evidence may express the results of several seasons of activity, the human skeleton, when correlated with archaeological and ethnographic data, provides information concerning daily activities performed throughout an individual's lifetime. Studies in occupational and sports medicine, along with electromyographic analysis of movement, have shown that different activities place different amounts of stress on human bone. In the present study, analysis of upper extremity musculoskeletal stress markers (MSM) has been used to clarify habitual activity patterns of two ancient Thule Eskimo groups from northwest Hudson Bay, Canada. Distinct pattern differences in muscle use occurred between Thule adult males and females and suggest possible gender-specific activity patterns that are not always discernible from the archaeological record alone. Temporal applications of the MSM data for Early and Late Period Thule support McCartney's theory of a substantial change in subsistence strategies through time, particularly among the adult males.  相似文献   

19.
The empirical investigation of several geophysical time series indicates that they are composed of segments representing different natural regimes, or periods when events are strongly autocorrelated. Using a data transformation method developed by Hurst, these regimes are differentiated by rescaling the time series and examining the resulting transformed trace for inflections. As regime signals are not completely mixed and have rather long run lengths, Hurst rescaling produces a clustering of extremes of the same sign and elevates the Hurst exponent to values greater than 0.5. These regimes have a characteristic distribution, as defined by the mean and standard deviation, which differ from the statistical characteristics of the complete record. Analysis of sunspot numbers, monthly precipitation records from the midwestern United States, and annual watershed discharge yield regimes that correlate to well-documented periods of extreme activity. Rescaling appears to be useful in screening time series of unknown characteristics to differentiate periods dominated by regime-specific physical processes.  相似文献   

20.
Practices of scavenging of Melbourne's hard rubbish collections are examined in the context of an emerging resource recovery waste regime linked with policy shifts that promote resource recovery over disposal through landfill. Waste regimes have many parallels with regimes in natural resource management and contestations over property are an important but neglected aspect. Based on research conducted primarily in the south eastern suburbs of Melbourne, I argue that hard rubbish on the kerb‐side forms an informal ‘waste commons’ that facilitates various forms of revaluing of municipal household waste. Results of a survey conducted by householders scavenging of their own hard rubbish piles suggest that informal scavenging activities were more effective for diverting waste from landfill by recycling than the formal processes of council hard rubbish contractors. Interviews conducted with residents, waste management contractors and self identified ‘professional’ scavengers revealed different perspectives on the waste commons and highlighted the contested nature of property in hard rubbish. Together with the survey findings, they allow tentative conclusions to be drawn about the role of the waste commons in the transition from a regime of disposal through landfill to one focused on resource recovery.  相似文献   

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