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51.
苏多杰 《攀登》2006,25(2):83-86
环境政策是西部民族地区环境保护的基石。西部民族地区现行的环境政策对保护西部民族地区环境,促进社会经济的发展起到了一定的作用。但不论从政策覆盖面、政策的深度,还是政策的配合和执行政策后所产生的效应来看,均存在许多不足。为了能最充分地发挥环境政策效应,本文设计了环境政策的基本框架,并提出了分类环境政策设计的思路。  相似文献   
52.
Flood risk mapping allows for informed decision making regarding personal and community planning. Resistance to flood risk mapping can be driven by potential decline of property values. This paper explores resistance to flood risk mapping through the lens of climax thinking. Climax thinking is a novel theory guiding explorations of resistance to proposed land use changes. The aim of this study was to understand flood experiences, the presence of resistance to flood risk mapping, and whether climax thinking could help explain this resistance. To address this, surveys were administered to residents in the Nova Scotian towns of Liverpool and Bridgewater. We found that one third of respondents have experienced flooding, yet the majority have not seen a flood risk map, nor were they concerned about the potential impacts of flooding. Only one sixth of respondents exhibited resistance to flood risk mapping because of potential loss to property value. Dimensions of climax thinking were predictive of this resistance, specifically ignorance of an individual's own ability to adapt and inability to recognize the impact of their adaptation decisions on others, which together quadrupled the predictive power of the ordinal regression model. These insights can be applied to support the acceptance of flood risk mapping.  相似文献   
53.
Louisiana’s coastal wetlands have been disappearing at an alarming rate over the past several decades, with the greatest harm experienced by vulnerable populations (poor and racialised residents). It was not until 2005 that the state legislature responded with a much-lauded Master Plan tasked with integrating the construction of new flood control infrastructure with wetland restoration. Seeking to unsettle this initiative, we develop a historical-geographical materialist approach to follow the entanglements between infrastructural production and capital accumulation in Louisiana over the past several hundred years. In so doing, we present a two-fold argument: that the making and mastering infrastructural violence has always been part of the historical unfolding of the socio-spatial dynamics of capitalism; and that infrastructural development has played an integral role in this duality at every historical turn. The capitalist state, at both the federal and state levels, has played a vital role in producing and controlling this violence.  相似文献   
54.
POTENTIAL IMPACTS OF GLOBAL SEA-LEVEL RISE ON CANADIAN COASTS   总被引:3,自引:0,他引:3  
The sea-level rise that may result from global climate change is placed within the context of past and present sea-level changes on Canadian coasts. To assess future impact, a dimensionless index of sensitivity is determined. Coasts with low, moderate, and high sensitivity constitute 67%, 30%, and 3% of the total coastline, respectively. The most sensitive regions are: (1) several parts of the Maritime Provinces; (2) two areas of the British Columbia coast; and (3) a large part of the Beaufort Sea coast. Impacts in four regions - Bay of Fundy, Beaufort Sea, Fraser Delta, and Eastern Shore of Nova Scotia - are discussed in detail. It is argued that the societal response to changes in sea level should favour retreat and accommodation strategies.
Il est possible que les changements climatiques globaux provoqueront une élévation du niveau de la mer. Nous examinons ce scénario dans le contexte des changements passés et présents du niveau de la mer sur les côtes canadiennes. Pour évaluer l'impact de l'élévation prévue un indice non dimensionnel de vulnérabilité est déterminé. Les côtes à la vulnérabilité basse, modérée et élevée constituent, respectivement, 67%, 30%, et 3% de tout le littoral. Les régions les plus vulnérables sont: (1) plusieurs régions dans les provinces maritimes; (2) deux zones sur la côte de la Colombie britannique; et (3) la plupart de la côte de la mer de Beaufort. Nous discutons en détail les impacts dans quatre régions, soit la baie Fundy, la mer Beaufort, la delta du Fraser et la rivage dit 'Eastern Shore' de la Nouvelle-Écosse. Nous estimons que la réponse sociale aux changements du niveau de la mer devrait favoriser des stratégies de retraite et d'accommodement.  相似文献   
55.
People whose livelihoods depend on the natural environment have detailed knowledge of the lands and waters surrounding their communities. This paper presents research on the traditional geographic knowledge of fish harvesters in Change Islands, Newfoundland. Our findings, based on “kitchen table mapping” and other ethnographic methods, demonstrate that residents of coastal communities have extensive geographic knowledge associated with a way of life centred on fishing. This knowledge is reflected in a “namescape” that includes hundreds of toponyms that are not present on existing maps and that reflect meaningful connections with local history and cultural heritage. Fish harvesters also have distinctive ways of conceptualizing the landscape and the seascape, which is reflected in the geographic terminology they use. Overall, their way of looking at the environment, in contrast to the bird's-eye perspective that prevails in western cartography, can be characterized as a “boat perspective”. Their geographic knowledge has practical value for improving existing cartographic information and developing sustainable resource use strategies. At a broader level, their distinctive ways of interpreting the “earthscape” provide alternative ways of understanding space and place, and can help us identify our assumptions about how we define geographic features and represent them on maps.  相似文献   
56.
Underwater excavations at the Classic period (a.d. 300–900) ancient Maya salt works of Chan b’i and Atz’aam Na in Paynes Creek National Park, Belize, reveal activity areas associated with a substantial salt industry for distribution to nearby southern Maya inland sites where this biological requirement was scarce. Wooden architecture and salt making artifacts are abundantly preserved in a peat bog composed of red mangrove. Excavations, screening, and analysis of recovered material at the submerged underwater sites reveal that the artifacts are overwhelmingly briquetage: pottery vessels used to evaporate salty water by heating over fires to make salt. The spatial distribution of briquetage in relation to the interior and exterior of buildings reveals that salt production was occurring indoors. The plethora of briquetage and the scarcity of domestic artifacts indicate that the sites were specialized salt works and not physically attached to households.  相似文献   
57.
Sites which have been occupied semi-continuously in the past present some inherent difficulties for archaeology. Here we present new research from a coastal site on the North Island of New Zealand at Cooks Beach where anthropogenic vegetation changes are seen using microfossil analysis of obsidian tools, sediments and pit fill. The results indicate the initial presence of people in AD 1300–1400 followed by subsequent periods of disuse or abandonment and sweet potato (Ipomoea batatas) cultivation. Around the time of initial settlement, obsidian from this location is found at sites across the country. After AD 1400 the area appears to be deserted for a century or more, after which we see evidence for the cultivation of sweet potato in AD 1500 as evidenced by extensive soil modification and numerous storage pits. There is no evidence of a permanent settlement at the site. The geographic distribution of Cooks Beach obsidian was constricted while the site was used for sweet potato cultivation, a pattern often attributed to increased warfare. It appears cultivation was abandoned after AD 1650 marking a second secession of use, a fact confirmed in AD 1769 when Captain Cook visited the area. We consider the possible drivers for the late abandonment of cultivation at Cooks Beach.  相似文献   
58.
Supported by the U.S. National Park Service's Historic Preservation Fund program, the Rhode Island Historical Preservation and Heritage Commission administered surveys of coastal archaeological sites damaged by 2012's Hurricane Sandy in Rhode Island, USA. This project documented the transformative effects of Hurricane Sandy on coastal archaeological sites, evaluated the eligibility of many of those sites for listing in the National Register of Historic Places, and provided new insights into ancient Native American coastal occupation. Notable project limitations include incomplete property access, bureaucratic delays, and a Tribal collaboration that fell short. Because preserving most of these erosion-prone sites through shoreline stabilization is unlikely, management efforts will consider preemptive archaeological salvage excavations. This case study may prove useful to archaeologists worldwide who are managing coastal sites threatened by rising sea levels and storms of increasing intensity and frequency.  相似文献   
59.
The Mesolithic of Southern Scandinavia, with comprises Denmark and Southern Sweden, has been an attractive area for research for several reasons, including the good preservation conditions at many sites. Most of the work has been concentrated on the southwestern part of Southern Scandinavia, but results from more recent investigations mean that other areas can also be analyzed. New finds in the last few years have given us a greater understanding of the Late Paleolithic settlement and of its relation of the Mesolithic. For the Early Mesolithic (10,000–8000 B.P.), interest has focused primarily on the small inland bog sites in the southern part of the area, where the coast has since been submerged. Farther north, where the land has been uplifted, evidence of coastal settlement has been documented. The Late Mesolithic (8000–6000 B.P.) is known chiefly on the basis of its large coastal settlements. In this period, there is also a larger and more varied collection of finds, which makes it possible to discern clear regional differences. There has also been considerable research on the transition from Mesolithic to Neolithic.  相似文献   
60.
何琼峰 《旅游科学》2012,26(5):65-75
本文以长江三角洲地区(以下简称长三角)和珠江三角洲地区(以下简称珠三角)9个优秀旅游城市为例,利用结构方程模型和4586份现场调查数据,探讨沿海城市游客满意度的内在机制、指数水平和IPA提升战略等规律性特征。研究发现,沿海不同城市和地区间游客满意度的内在机制具有"基本一致"的规律,而长三角游客满意度的指数水平相对强于珠三角。应以改善涉旅行业现场服务为核心,因地制宜地提升沿海城市游客满意度。  相似文献   
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