Urban evolution in the USA

On a sustained basis, cities are of non-uniform relative sizes.This paper addresses three basic issues which arise from thissimple observation by examining the size distribution of UScities over the period 1900–1990. First, we explore thereasons why there is a wide distribution of city sizes. Second,we characterize the evolution of the size distribution of cities,documenting growth in sizes and numbers of cities. We ask whetherthe relative size distribution of cities has remained stableover time, or if it has displayed, instead, a tendency to collapse,flatten, or otherwise change its shape. We also examine evidenceon whether the size distribution obeys Zipf's Law. Third, weexamine the degree and determinants of mobility of individualcities within this distribution, asking to what extent citiesare moving up and down in the distribution and how this movementis influenced by cities' geographic characteristics. We usea newly constructed data with consistent metropolitan area definitionsover this century, discussing the issues and linking our resultsto the relevant literature.     

Evidence for volcanic ash fall in the Maya Lowlands from a reservoir at Tikal,Guatemala

Powder X-ray diffraction and petrographic analyses of reservoir sediments from Tikal, Guatemala have identified significant quantities of decomposed volcanic ash in the form of smectite and euhedral bipyramidal quartz crystals. X-ray fluorescence trace element content analysis was used to eliminate distant Sahara-Sahel and Antilles sources. The Zr/Y and Ni/Cr ratios of reservoir sediment from Tikal are consistent with a source from Central American volcanism (e.g., Guatemalan and Salvadoran). AMS radiocarbon dating of the smectite and crystalline quartz-rich reservoir sediments show that volcanic ash fell during the Preclassic, Classic, and Postclassic Maya cultural periods. It may now be possible to develop an effective chronology of ash fall at Tikal and the greater Peten.     

‘Kingdom Come’: Representing Mormonism through a geopolitical frame

This paper extends the reach of ‘popular geopolitics’ by exploring the geopolitical frame that American popular/news magazines use to portray a major religion in the United States: the Church of Jesus Christ of Latter-day Saints (the most prominent body known as Mormonism). It asserts that magazines often represent this type of Mormonism as a geopolitical entity, and sometimes even as a geopolitical threat. Prior to the early twentieth century, these portrayals were hegemonic, given the national government's distrust of Mormonism. But echoes of an earlier and more virulent geopolitical discourse have persisted, long after the federal government made its peace with Mormonism. This paper defines and analyzes twentieth-century magazines' geopolitical discourse on Mormonism, particularly in relation to Mormon spatiality. In doing so, it puts forward concepts of geopolitical optic and logic in order to more effectively distinguish between variations in geopolitical language.     

No Grounds for Conversation: The Regional Construction of Fundamental Difference between Mormonism and Socialism

This paper explores a missed opportunity for serious conversation or even alliance between some adherents of socialism and Mormonism. The Americanization of Mormons and Utah around 100 years ago opened Mormons up to broader alliances than had been possible during most of the 19th century. A few Mormons and socialists thought that intersections between the two groups' egalitarian ideologies could be fruitfully explored. However, this potential evaporated as Mormonism and socialism were culturally constructed as antithetical within regional life. Through this case, the paper comments on alliance-building strategies within radical politics and the practice of critical human geography.     

An assessment of the magnetic response of an iron‐smelting site*

The magnetic response derived from an iron‐smelting site was investigated by comparing magnetometry and magnetic susceptibility geophysical survey data and laboratory analyses of the magnetic characteristics of the furnace and slags. Magnetic analysis and microscopy (optical and SEM) of samples from the furnace lining and the slag deposits demonstrated the heterogeneity in the magnetic, morphological and mineral compositions of both materials. The comparison of the magnetic characteristics of the material with the geophysical survey data illustrated the importance of using both magnetometry and magnetic susceptibility survey techniques to maximize the information from an iron‐smelting site. The furnace was dated archaeomagnetically to the 14th century ad . The results demonstrate that the magnetic analysis of iron‐smelting sites is highly valuable, both to characterize sites and to improve the understanding of early iron‐working technology.     

Engagement,estrangement or divorce? The new universities and their communities in the 1960s

The new universities of the 1960s were innovatory, in their curricula, architecture, independence and academic ambitions. They also marked a different relationship between universities and their localities. For a century, new universities had been predicated on local demand, whereas the 1960s universities were conceived of as national institutions meeting a national demand. This new approach to university–civic connections was sudden, novel and contributed to a sense of remoteness attached to the new universities. This paper examines how the different policy was formulated, predominantly by the UGC, and considers some examples of how the policy played out in practice.     

Assessment of Riparian Revegetation Trials on In-Channel Benches in the Hunter Valley of Southeast Australia

Large-scale river training works have been carried out in the Hunter valley since 1955 in response to flood-driven channel changes. Vegetation was planted on in-channel benches induced by river training works to consolidate the deposits and to increase channel boundary roughness. Exotic species of vegetation such as willows and poplars were previously used. In 1983, ten trial sites were planted with various species of native vegetation. Survival rates were evaluated in 1987 and 1997. The most successful species planted was Eucalyptus camaldulensis with an overall survival rate of 77 per cent in 1997. The Acacia species were found to be short-lived, exhibiting a significant decline in survival rates between 1987 and 1997. Survival rates for most species were higher on sand-bed than on gravel-bed sites. This difference may be attributed to better drainage on benches at the sand-bed sites. Investigations of flood disturbance showed that between 1983 and 1997 the sites were flooded between four and 13 times. The survival rates of Grevillea robusta and Eucalyptus melliodora trees were negatively correlated with the total number of recorded floods at each site. Poor natural regeneration of planted species is attributed to a combination of periodic flooding, intensive weed growth, low light intensities at ground level and grazing disturbance. These trials were not well designed for statistical analysis but provide valuable long-term information on the suitability of various species for planting in riparian rehabilitation programs. Such information is of relevance not only to river and catchment management authorities, but also to community groups.