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Erica Schoenberger 《The Professional geographer》1991,43(2):180-189
The open-ended corporate interview as a qualitative research method is proposed as a valuable component of an evidentiary strategy in economic geography. It is argued to be more sensitive than other survey methods to historical, institutional, and strategic complexity. The corporate interview method is particularly appropriate in periods of economic and social change that challenge traditional analytical categories and theoretical principles. Some problems inherent to the method, and strategies for minimizing their impact on the research project, are described. 相似文献
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Peter G. Dahlhaus Timothy J. Evans Erica L. Nathan Jim W. Cox Craig T. Simmons 《Hydrogeology Journal》2010,18(7):1611-1623
The connection between the removal of native vegetation, rising water tables and increasing stream salinity has been established for many catchments across Australia. However, the West Moorabool River in south west Victoria is an example of a catchment where there has been little discernable effect on groundwater levels following land clearing. Over the past 150 years, a significant portion of the catchment has been cleared of dense forest for agricultural development. Historic standing water-level records from 1870–1871 and 1881 are compared with contemporary measurements (1970s to 2007) recorded in the government bore databases. The data show that the earliest recorded groundwater levels are well within the seasonal range of values observed today. By integrating geology and hydrogeology with historical observations of groundwater levels, climate data and land use, the contemporary field observations of stream salinity are linked to the changed water use and shift in rainfall. In contrast to the normally accepted axiom, reafforestation as a management strategy to mitigate the rising salinity in the West Moorabool River catchment would seem inappropriate. 相似文献
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Pierre Pepin Erica J.H. Head 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(6):989-1002
We report on the variation in energy reserves of individual C5 copepodites of Calanus finmarchicus from the Newfoundland continental shelf and the Labrador Sea collected from surface and overwintering (or bottom) depths prior to, during and after the expected timing of the onset of diapause. Overall, the trend was for a decreasing average prosome length as the year progressed for all locations although the decline was smallest in the Labrador Sea and greatest in the deep waters of the continental shelf. The size of the oil sac was closely linked to the weight of the copepodite but the form of this relationship showed substantial variations with depth and season. We show a clear increase in the relative oil sac volume for C. finmarchicus between late spring and late summer, by which time some animals had descended to diapause depths. The progressive decrease in oil sac volume of animals sampled at depth in the Labrador Sea between September and December suggests a significant loss of energy reserves during diapause. From the distribution of volumes and body sizes in December we estimate that 23–53% of individuals would not be able to meet the energetic cost of moulting and early gonad development. Overall, some of our observations appear to invalidate earlier hypotheses concerning the governing role of lipids in the life history of C. finmarchicus. However, assessment of the factors that influence entry into dormancy should be based on the relative probabilities of alternative strategies for successful reproduction (e.g. entering dormancy vs. continuing into a second generation). 相似文献
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We note that different models, providing comparably good interpretation of the hard X-ray properties of so-called Masuda sources,
can make distinctly different predictions for the radio emission produced at the Masuda source by the same population of accelerated
electrons. Accordingly, we calculate the radio emission within a few competing models, i.e., those involving magnetic, turbulent, and collisional trapping of the fast electrons in the coronal source. We show that
even available incomplete radio observations of the classical Masuda event and a Masuda-like event on 31 December 2007, recently
reported by Krucker et al. (Astrophys. J.
714, 1108, 2010) are highly valuable in restricting the physical model of the source. Furthermore, our study proposes that combination of
more complete high-resolution X-ray and radio observations can allow unambiguous distinction between the competing Masuda
source models. 相似文献
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Natural Hazards - The 2018 Camp Fire caused significant damages to the education and healthcare systems in the town of Paradise, CA. This paper presents the findings of a qualitative case study... 相似文献
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Noelia?Liliana?AlchaparEmail author Claudia?Cotrim?Pezzuto Erica?Norma?Correa Lucila?Chebel Labaki 《Theoretical and Applied Climatology》2017,130(1-2):35-50
This paper describes different ways of reducing urban air temperature and their results in two cities: Campinas, Brazil—a warm temperate climate with a dry winter and hot summer (Cwa), and Mendoza, Argentina—a desert climate with cold steppe (BWk). A high-resolution microclimate modeling system—ENVI-met 3.1—was used to evaluate the thermal performance of an urban canyon in each city. A total of 18 scenarios were simulated including changes in the surface albedo, vegetation percentage, and the H/W aspect ratio of the urban canyons. These results revealed the same trend in behavior for each of the combinations of strategies evaluated in both cities. Nevertheless, these strategies produce a greater temperature reduction in the warm temperate climate (Cwa). Increasing the vegetation percentage reduces air temperatures and mean radiant temperatures in all scenarios. In addition, there is a greater decrease of urban temperature with the vegetation increase when the H/W aspect ratio is lower. Also, applying low albedo on vertical surfaces and high albedo on horizontal surfaces is successful in reducing air temperatures without raising the mean radiant temperature. The best combination of strategies—60 % of vegetation, low albedos on walls and high albedos on pavements and roofs, and 1.5 H/W—could reduce air temperatures up to 6.4 °C in Campinas and 3.5 °C in Mendoza. 相似文献