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61.
Larry V. Benson 《Journal of Archaeological Method and Theory》2011,18(1):61-109
Chemical and nutrient analyses of 471 soil samples from 161 sites within four archaeological regions (Pajarito Plateau/Bandelier, Zuni, Mesa Verde, and the Chaco Halo) were combined with historical climate data in order to evaluate the agricultural productivity of each region. In addition, maize productivity and field-life calculations were performed using organic-nitrogen (N) values from the upper 50 cm of soil in each region and a range (1?C3%/year) of N-mineralization rates. The end-member values of this range were assumed representative of dry and wet climate states. With respect to precipitation and heat, the Pajarito Plateau area has excellent agricultural potential; the agricultural potentials of the Zuni and Mesa Verde regions are good; and the agricultural potential of the Chaco Halo is poor. Calculations of N mineralization and field life indicate that Morfield Valley in Mesa Verde should be able to provide 10 bu/ac of maize for decades (without the addition of N) when organic N-mineralization rates exceed 2%. Productivity and field-life potential decrease in the following order: Zuni, Mesa Verde, Bandelier, Chaco Halo. The Chaco Halo is very unproductive; e.g., 10 bushels per acre can be achieved within the Halo only from soils having the highest organic N concentration (third quartile) and which undergo the highest rate (3%) of N mineralization. 相似文献
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Tim Brown 《Social & Cultural Geography》2013,14(4):489-506
The aim of this paper is to suggest an analytical framework through which the complex question of hospital closure and local protest can be further explored. The significance of this area of study lies with the extraordinary events that surrounded a campaign to save the Kidderminster General Hospital from downsizing. Whilst the hospital was not saved, the local campaign committee organizing the protest took their fight into the political arena and were successful in gaining a parliamentary voice in the 2001 general elections. Such an achievement has had considerable political implications, however, the question asked here is how might we begin to interpret the events that took place. To this end, the paper draws on current geographical literature in an attempt to construct a framework that accounts for both national policy debates and the local context within which such campaigns emerge. 相似文献
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The suitability of imagery from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA series of satellites for the synoptic classification of circulation trends in the European Arctic is assessed with reference to data from three climate stations. Simplified synoptic cyclonic classifications are derived from the satellite imagery and tested against climate data. Five classes of frontal system are derived from the tracking of systems over the UK‐Scandinavia‐Baltic region using 1460 satellite images over two years. An index based on the qualitative interpretation of satellite imagery was related to the reference data. The tracking of the systems in the imagery also facilitates a comparison of travel times across the region and the frequency of occurrence. Frontal systems that remain largely stationary over the Baltic were found to correlate best with precipitation at the reference sites. The paper thus investigates the use of AVHRR imagery for the categorisation of weather patterns towards deriving quantitative relationships between circulation classes and weather elements (such as temperature and precipitation) where, for example, climate data are sparse or where skills required for the interpretation of Height Potential Fields are lacking. 相似文献
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Katrina Myrvang Brown 《Scottish Geographical Journal》2013,129(2):109-129
In Scotland, as elsewhere in Western Europe, many examples of historical common land have endured to the present day, but are under major pressure from the economic restructuring, socio-cultural recomposition and changing policy context that characterise contemporary rural change. For the crofting common grazings of Scotland, two particular challenges have arisen in the form of: (1) the growing difficulty of gaining sufficient livelihood contributions from traditional agriculturally-based activities; and (2) the increasing heterogeneity of rights-holders. This paper elaborates the findings of a recent survey, which sought to identify the main implications of these challenges for common grazings use and governance. An overall decline in levels of use of common grazings was identified, as well as decreasing involvement and investment in associated local institutions. This informs a discussion of the factors shaping the role of historical common land in contemporary rural spaces, an area neglected in the common property literature. 相似文献
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Schoville Benjamin J. Brown Kyle S. Wilkins Jayne 《Journal of Archaeological Method and Theory》2022,29(1):162-187
Journal of Archaeological Method and Theory - Humans occupy a wide range of environments, including those that experience water stress. Our species has a long history of mitigating arid and... 相似文献