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ABSTRACT. In the nineteenth century, local‐scale roads in central Kentucky were built subject to local knowledge and cultural tradition but within the context of legal authority and folk‐ or science‐based engineering precepts. This study demonstrates how legal and engineering standards‐though conceived as transcendent and objective‐were in fact contingent on the region's physical attributes as well as its cultural traditions and character. Thus local road alignment and construction have been influenced by and contingent on local knowledge, dialogue, and debate since frontier times.  相似文献   

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ABSTRACT. Together, urbanization and the search for sustainable development present a dilemma in the Brazilian Amazon: how to accommodate an expanding urban population while creating and maintaining sustainable production systems that feed the people and manage the forest. A unique peri‐urban agroforestry project, implemented by a municipal government in western Amazonia and concerned with a citywide influx of rural agriculturalists and former forest‐dwelling extractive producers, is examined as a source of food and self‐determination. Peri‐urban agroforestry seems to be a viable option for other Amazonian cities that are experiencing increasing urbanization and its associated problems.  相似文献   

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ABSTRACT. Pressured by structural adjustment loan conditions, Côte d'Ivoire reduced state support for rice production and processing during the 1990s. In this article we examine how various actors in the rice commodity chain adapted to the macroeconomic reforms. Following a brief history of the rice sector, we present the results of fieldwork based on interviews conducted in 2002 of farmers, millers, traders, and workers in the state extension service and nongovernmental organizations. We found that, in the absence of state supports for farmers, private millers became the focal point of regional producer‐processor rice networks. The four networks identified became the sole source of domestic commercial rice when the state removed subsidies for fertilizer and modern seeds, privatized extension, and liberalized prices and imports. To increase their role in the national rice supply, the rice networks may need support through microlending and a focus on niche markets.  相似文献   

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The Malaysian government regards the country's indigenous peoples as “backward” and in need of “modernization.” It aims to assimilate them into the so‐called mainstream society and to incorporate their lands and resources into national and global markets. These policy objectives leave little scope for indigenous groups to pursue their own life projects. Indigenous communities want to share in the benefits of economic development, but they are not prepared to give up their lands, cultures, and identities to obtain them. They have attempted to ward off the negative consequences of development projects by forming advocacy nongovernmental organizations, engaging in various forms of resistance, and seeking redress of their grievances in the courts. Most of all, they want recognition of their rights to land and place. The efficacy of their agency is severely hampered by a battery of repressive laws and by their own political weakness.  相似文献   

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ABSTRACT. In the first half of the twentieth century French academic geography did not present a unified front: The “outsiders” Jean Brunhes and Pierre Deffontaines offered a vision of la géographie humaine that did not conform to the one proclaimed by Vidal de La Blache and his disciples. After sketching the careers of Brunhes and Deffontaines, this essay explores the network of connections between the academic editor Deffontaines and the contributors to the Geographie Humaine series published by Gaston Gallímard. As committed Christians, Brunhes and Deffontaines emphasized the realm of ideas, values, and decision making, as well as their tangible realization and visual expression in cultural landscapes. Both men saw the discipline of geography as a means of celebrating the diversity of the world and the popularization of geography as a way of promoting international understanding and tolerance. Their inclusivity and interaction with other academic disciplines are relevant to current practitioners of cultural geography.  相似文献   

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Information on the rates, characteristics, and drivers of land‐use change are vital for addressing the impacts and feedbacks of change on environmental processes. The U.S. Geological Survey's Land Cover Trends project is conducting a consistent, national analysis of the rates, causes, and consequences of land‐use change. In this article we assess change in the Atlantic Coastal Pine Barrens ecoregion from 1973 to 2000. Urban lands expanded by more than 900 square kilometers during the study period. Land‐use change in the ecoregion followed the tenets of “Forest Transition Theory” (ftt ) prior to the study period, but forest lands experienced consistent declines from 1973 to 2000. Increasing government regulation during the study period, consistent with concept of the “Quiet Revolution” (qr ), mitigated forest loss during the latter half of the study period. Generalized theories, including ftt and the qr , are valuable, but local and regional determinants of comparative land rents ultimately drive land‐use change at this scale.  相似文献   

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ABSTRACT. Rural private lands in the Mountain West of the United States are undergoing a profound land‐use conversion, from agriculture to low‐density residential or exurban development, though little scientific study documents the ecological consequences of this change. Nongovernmental conservation organizations are working with ranchers to keep rangeland out of development and in ranching, ostensibly because these organizations believe that biodiversity is better protected on ranches than on exurban developments. We compared plant and wildlife communities across the principal rural land uses in the Mountain West: protection, livestock ranching, and exurban development. Native plant and faunal biodiversity was better maintained on ranches and protected areas than on exurban developments. Exurban developments favored species that were nonnative or adapted to human‐altered environments. The continued conversion of ranches to exurban development suggests a long‐term alteration of the region's natural heritage.  相似文献   

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Debris flows and debris floods cause frequent geomorphic hazards, even in the mid‐mountains of Central Europe. In the Hrubý Jeseník Mountains (Eastern Sudetes, Czech Republic), strong anthropogenic interventions have created specific conditions for erosion, transport and accumulation of material released by debris flow/flood events. We present a detailed spatio‐temporal reconstruction of the hydro‐geomorphic process activity in two adjacent sub‐catchments using dendrogeomorphic methods applied to the steep, narrow channels. An analysis of 172 sampled trees [Picea Abies (L.) Karst.] revealed 14 torrential events since 1943 in the Klepá?ský stream sub‐catchment and 11 events since 1897 in the Keprnický stream sub‐catchment. Identical events were identified in 1965, 1991, 1997, 2002 and 2010. The event return periods were comparable with return periods from the foothills of the European Alps. A higher frequency of events in the first sub‐catchment may be caused by the presence of a deep‐seated landslide, steeper slopes and a higher susceptibility to shallow slope deformations. Different spatial patterns of events were presented using the Kernel Density analysis in ArcMap 10.1. Clusters of affected trees in the valley floor during the last decades may be due to increased erosion below the check dams and increased accumulation above. The presence of check dams and slope stabilization works since the 1960s has mitigated the processes in several gullies, but due to the current non‐interventional management, the risk of their damage is increasing, particularly when increased activity is observed in the adjacent unprotected gullies.  相似文献   

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Vehicle‐related hyperthermia is an unfortunate tragedy that leads to the accidental deaths of children each year. This research utilizes the most extensive dataset of child vehicle‐related hyperthermia deaths in the United States, including 414 deaths between 1998 and 2008. Deaths follow a seasonal pattern, with a peak in July and no deaths in December or January. Also, deaths occurred over a wide range of temperature and radiation levels and across virtually all regions, although most of them took place across the southern United States. In particular, the Phoenix, Houston, Dallas, and Las Vegas metropolitan areas had the greatest number of deaths. We utilize our vehicle hyperthermia index (vhi ) to compare expected deaths versus actual deaths in a metropolitan area, based on the number of children in the area who are under the age of five and on the frequency of hot days in the area. The vhi indicates that the Memphis, West Palm Beach‐Boca Raton, and Las Vegas metropolitan areas are the most dangerous places for vehicle‐related hyperthermia. We conclude by discussing several recommendations with public health policy implications.  相似文献   

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A unique, continuous, fan‐shaped belt of sandy landforms in the central‐eastern Mazovian Lowland, Central Poland has been investigated using a multiproxy dataset of sediment physical properties and chronological framework. Although there are several previous studies of similar fan‐like forms elsewhere in Central Poland, this central‐eastern part has not been investigated in detail. A combined methodological approach, using grain‐size distributions, the roundness, surface character and microtexture of quartz grains, and the mineral composition of the light and heavy fractions, indicate a predominantly aeolian origin for the fan‐like forms. Overlying them are dunes, the sediment within which is derived mainly from the fan‐like forms. Two main aeolian phases are distinguished based on luminescence ages: (1) between around 15 and 16 ka, possibly correlated with the Pomeranian Phase of the last (Vistulian) glaciation in Poland, and representing a phase with a poorly recorded deflation event; and (2) around 12 ka, associated with the Younger Dryas onset, when fresh, non‐aeolian material was delivered to the system. Overall, the palaeoenvironmental pattern of the fan‐like forms is controlled by the Upper Pleistocene aeolian trends.  相似文献   

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In the mid‐Cretaceous Lasarte sub‐basin (LSB) [northeastern Basque‐Cantabrian Basin (BCB)] contemporaneous and syn‐depositional thin‐ and thick‐skinned extensional tectonics occur due to the presence of a ductile detachment layer that decoupled the extension. Despite the interest in extension modes of rift basins bearing intra‐stratal detachment layers, complex cases remain poorly understood. In the LSB, field results based on mapping, stratigraphic, sedimentological and structural data show the relationship between growth strata and tectonic structures. Syn‐depositional extensional listric faults and associated folds and faults have been identified in the supra‐detachment thin‐skinned system. But stratigraphic data also indicate the activation of sub‐detachment thick‐skinned extensional faults coeval with the development of the thin‐skinned system. The tectono‐sedimentary evolution of the LSB, since the Late Aptian until the earliest Late Albian, has been interpreted based on thin‐ and thick‐skinned extensional growth structures, which are fossilized by post‐extensional strata. The development of the thin‐skinned system is attributed to the presence of a ductile detachment layer (Upper Triassic Keuper facies) which decoupled the extension from deeper sub‐detachment basement‐involved faulting under a regional extensional/transtensional regime.  相似文献   

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This paper investigates the application of the peaks‐over‐threshold method in combination with fitting of the generalized Pareto distribution for estimating the frequency of high‐magnitude geomorphic events, on the basis of tree‐ring data. In particular, attention is focused on extreme value distribution of tree‐ring responses and in the minimum threshold or index number required to assure the past occurrence of high‐magnitude events. The objective is to set a threshold, adapted to the sample distribution, which will make the distinction between high‐magnitude years and remaining years, where the response of sampled trees is too weak to be attributed to a high‐magnitude geomorphic event. The statistical framework proposed is based on the statistics of extremes. Through the use of simple, strong and effective mathematics, this model should strengthen the position of dendrogeomorphology in the evaluation and management of natural hazards.  相似文献   

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ABSTRACT. Fires on Sumatra and Kalimantan have taken a heavy toll on Indonesia' remaining tropical forests. Drought exacerbates the fire hazard, but it does not cause the fires, most of which have been the result of inappropriate land‐use policies and practices. Peatland fires have emitted vast quantities of smoke that periodically blanket large parts of insular Southeast Asia, impairing visibility, disrupting travel, hampering economic activity, and posing serious health risks. The development agenda of Indonesia' New Order regime paid scant attention to forest management, including the need to detect, control, and suppress unwanted fires.  相似文献   

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ABSTRACT. The house‐lot garden in central Mexico is gendered space where changing cultural identities are negotiated, re‐created, and celebrated as “tradition” is continually redefined. No clear boundary separates the kitchen from the house‐lot garden or the private space of the household from the semipublic space of the community. During collective food preparation for religious fiestas, gendered reciprocity networks strengthen community relations and foster alliances between traditional neighborhoods and between communities in the region. At the intersection of everyday life and fiestas, food‐preparation spaces, or kitchenspaces, in the house‐lot garden are fertile areas in which to explore the cultural reproduction of nature‐society relations. They are vital to understanding gender, place, and culture in this region and represent people's symbolic connection with the land in increasingly urban contexts. This article analyzes the sense of place that Mexican women derive from their house‐lot gardens.  相似文献   

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ABSTRACT. Many mountain peoples face water and environmental health problems. At particular risk is the health of women and of children who live in remote and marginalized mountain areas. Environmental health concerns are often associated with the waterborne parasitic and endemic diseases responsible for much child morbidity and mortality in the Karakoram‐Himalaya of northern Pakistan. Poor environmental health and water‐quality conditions affect child survival, and challenges to viable local interventions are severe. Transformations in women's productive and reproductive work have health consequences for children, and gender and household dynamics shape and mediate women's responses to environmental health risks. Significantly, these findings draw attention to the need for improved water and health policy, especially policy that recognizes different gender and child‐care roles in mountainous regions of the developing world.  相似文献   

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The detailed clay varve chronology and an extensive knowledge of the highest postglacial shore level elevation (HS) in northern Sweden, along the Bothnian western coast, provides opportunities for determining the pattern of isostatic rise and centre of uplift from the early Holocene. The shore level of c. 10 100 cal yr bp (10 ka) for this area is determined by subtracting, from the metachronous HS elevations, the fall in relative sea level between local deglaciation time and the chosen reference time. The area of highest uplift since 10 ka is situated somewhat north of the location with the world‐record HS (Skuleberget in Ångermanland), but south of the area with most rapid current rise. Wave erosion marks in the studied area are seen to be more consistent indicators of HS than glaciofluvial delta levels. The gradients of shore marks at 10 ka are generally small within the investigation area. The regional 10 ka shore level pattern shows considerable irregularity compared to the current uplift. Central Sweden and western Finland show 10 ka gradients that indicate isostatic response to late (13–10 ka bp ) glacial unloading. Indications of a secondary uplift centre west of the present investigation area are reported in previous work; this also suggests rapid isostatic response to unloading. Finally, the possibility of identifying errors in the varve‐dated deglaciation chronology via the 10 ka shore level pattern is illustrated.  相似文献   

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