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41.
Larry V. Benson 《Journal of Archaeological Method and Theory》2011,18(1):1-60
Maize is the New World’s preeminent grain crop and it provided the economic basis for human culture in many regions within the Americas. To flourish, maize needs water, sunlight (heat), and nutrients (e.g., nitrogen). In this paper, climate and soil chemistry data are used to evaluate the potential for dryland (rain-on-field) agriculture in the semiarid southeastern Colorado Plateau and Rio Grande regions. Processes that impact maize agriculture such as nitrogen mineralization, infiltration of precipitation, bare soil evaporation, and transpiration are discussed and evaluated. Most of the study area, excepting high-elevation regions, receives sufficient solar radiation to grow maize. The salinities of subsurface soils in the central San Juan Basin are very high and their nitrogen concentrations are very low. In addition, soils of the central San Juan Basin are characterized by pH values that exceed 8.0, which limit the availability of both nitrogen and phosphorous. In general, the San Juan Basin, including Chaco Canyon, is the least promising part of the study area in terms of dryland farming. Calculations of field life, using values of organic nitrogen for the upper 50 cm of soil in the study area, indicate that most of the study area could not support a 10-bushel/acre crop of maize. The concepts, methods, and calculations used to quantify maize productivity in this study are applicable to maize cultivation in other environmental settings across the Americas. 相似文献
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Counties identified as anomalous in the 2004 US presidential election - large metropolitan counties and majority-minority counties that voted Republican and non and small-metropolitan counties that voted Democratic, are the subject of a qualitative analysis to assess why they were exceptions to the conventional wisdom of a Red and Blue America polarized along metropolitan-non-metropolitan and modern versus traditional dimensions. Contacts with professional colleagues, and with media and partisan representatives, and visits to selected counties provided valuable insights and helped us to assess the extent to which the county votes in 2008 reinforced or changed the broad Red and Blue dimensions derived from 2000 to 2004. 相似文献
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Larry Bissett 《Journal of regional science》1975,15(3):391-395
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Gay bars have been central to the social and cultural geography of queer folk throughout the twentieth century. In North America, Liquor Control Boards have been important in governing homosexuality. In order to explore the spatial governance of homosexuals, this paper uses a Foucauldian governmentality perspective to analyze data from Washington State Liquor Control Board (WSLCB) enforcement and hearing files between 1934 and 1971. While the WSLCB governed heteronormatively, it did so with a relatively light touch through the deployment and selective enforcement of often vague administrative rules. Adherence to the rules, meanwhile, relied upon an ability and willingness to understand authorities’ intentions and imaginations and to self-govern accordingly. Gay bars were somewhat privileged vis-à-vis neighboring straight bars, due to the unintended consequences of certain state practices, a desire by state authorities to closet homosexuality generally, and a propensity for self-governance on the parts of gay bar owners, managers, and patrons. Our findings add nuance to work on Foucauldian studies in geography, work on licensing and regulation, and urban gay histories. 相似文献
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Larry A. Swatuk 《International affairs》2002,78(3):507-530
UN Secretary–General Kofi Annan has identified water and sanitation as a principle area of focus for the forthcoming World Summit on Sustainable Development (WSSD). It is fitting that this meeting is being held in Johannesburg, as water resources management issues are of primary importance to the southern African region. There is a new water architecture being developed in the region, one that hopes to correct abiding structural inequalities of access between and among states, communities and peoples. Part of this new water architecture includes an enhanced role for the private sector and 'the market' in the provision and management of this crucial resource. This is a role that many feel will exacerbate rather than alleviate historically derived problems of underdevelopment. It is a role, therefore, that may undermine many of the positive developments that have taken place in the region over time. If regional leaders are interested in sustainable and equitable water resources management, they must be prepared openly to debate this issue with all interested parties not only at the WSSD, but also in the region and beyond. 相似文献
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Larry Bissett 《Journal of regional science》1978,18(3):495-501