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151.
Ralph E. J. Boerner Michael N. DeMers John W. Simpson Francisco J. Artigas Alejandra Silva Leslie A. Berns 《Geographical analysis》1996,28(1):56-66
This study examined landcover change during 1940–1988 in two contiguous landscapes of approximately 12,400 hectares in central Ohio, USA: an inertial till plain area and a more dynamic moraine area. Agriculture dominated both landscapes throughout, however, the cover of natural vegetation and urban-suburban development increased over time on the moraine while natural vegetation decreased and agriculture increased on the till plain. Markov process models for landcover change were constructed for three 14–17-year time intervals and for the entire forty-eight-year study period. Probabilities of self-replacement for agricultural lands (0.91–0.97) were higher and those for forests (0.54–0.65) lower than those reported for other landscapes. Predictions of landcover percentages for fifty years in the future were made using Markov process models derived from actual cover changes in 1940–1957, 1971–1988, and 1940–1988. All three models produced similar predictions for the inertial till plain area. In contrast, the three models' predictions differed considerably for the moraine area. Only the 1971–1988 transition matrix was sensitive to increases in urbanization and reforestation which began on the moraine in the 1970s. These results indicate that reliance on lengthy study intervals and net rates of change can obscure spatial and temporal patterns of landcover change that are caused by natural and socioeconomic factors operating on shorter time scales. 相似文献
152.
153.
David O. Rafter 《European Planning Studies》1996,4(2):225-236
The concept of sustainability has become a significant consideration in planning in Europe and the US. At both the international and the national level, urban planners and policymakers have developed a package of policies designed to produce sustainable growth and development. In transport, this has been interpreted to mean that we need to increase accessibility while we reduce mobility by shifting trips from automobile to walking, bicycle or public transport modes. Using this criteria, the latest Dublin transport plan has been found to be only partially effective. Similar to many American transport plans, the DTI has opted for the infrastructure‐related sustainability policies and avoided the less popular economic disincentives. 相似文献
154.
David Downes 《Australian journal of political science》1996,31(2):175-190
The ecologically sustainable development (ESD) process represented a significant attempt by the Commonwealth Government to involve pro-environment and pro-development protagonists in a major environmental consultative forum. The government's inclusion of peak interest organisations into an exclusive consultation process resembles a neo-corporatist approach to interest intermediation. However, neo-corporatist theory has been applied almost exclusively to economic policy areas and interest organisations representing capital, labour and the state. Analysing the involvement of select environmental organisations in the ESD process, this paper argues that neo-corporatist theory can be extended to include non-production-based interest organisations. The implications of environmental organisation participation in a neo-corporatist structure are examined, including a discussion of the tension between neo-corporatist and new social movement theories. 相似文献
155.
ADA W. PRINGLE 《Geographical Research》1996,34(1):58-80
The history of dredging is examined for Cleveland Bay, 1883–1988, as the port of Townsville developed. Between 1883 and 1964 only intermittent data exist on localities, depths and quantities dredged but later much more detailed records are available for analysis. Geomorphological problems emerged and are considered with particular reference to material forming the seabed, the sediment yield from the coastal catchments and its seasonally and annually irregular delivery to the coast by the rivers, and sediment movement within the bay in response to wind, wave and tidal processes. Analysis of aerial photographs, 1941–1988, has enabled some dredging effects to be studied, especially relating to localised land reclamation and more widespread probable effects on seagrass beds and mangroves. 相似文献
156.
157.
The repeated failure to design and appropriately target policies and interventions which address the needs of rural peoples in Africa suggests that something may be wrong with our understanding of the way that these peoples live their lives. Perspectives which focus on intra-household processes, and on gender issues in particular, represent useful advances in the way that the social and economic lives of Africa's rural peoples are conceptualized. However, this article questions the value of adopting development planning, policy and project approaches based on the rigid identification of `gender roles'. By reference to field research undertaken in northern Ghana, the paper aims to demonstrate that other social constructs, such as marital status and seniority, may be as important as gender in determining the roles and status of individuals in African rural societies. The article concludes by highlighting a number of practical implications of this finding in terms of the structuring of development-oriented research and the targeting of policy and interventions. 相似文献
158.
Some 630 Roman silver coins excavated at Augusta Raurica (Switzerland) have been analysed by non-destructive X-ray fluorescence and X-ray diffraction. Furthermore, the density and the weight have been determined. The measured average density of plated and massive depletion-silvered coins is lower than the density calculated from the chemical composition, whereas massive coins display equal values for both of the densities. Based on experimental X-ray investigations of modern silver (tempering, acid treatment, production of corrosion layers), the nature of corrosion products on silver, their impact on surface analysis, and aspects of wearing-off by circulation are briefly discussed. 相似文献
159.
SPATIAL DEPENDENCY OF SEGREGATION INDICES 总被引:3,自引:0,他引:3
David W.S. Wong 《The Canadian geographer》1997,41(2):128-136
A few researchers have mentioned the scale sensitivity of segregation index, D. In this paper, I discuss analytically and empirically why using large enumeration areal units usually results in low segregation measures, and using small areal units produces relatively high segregation measures. The discussion is also applicable to the multi-group variant of D. A major finding is that if people of the same ethnic groups are positively spatially auto-correlated, increasing the size of areal units of analysis may not lower D initially, because only people of the same group are added. But enlarging the areal units subsequently may include population of other ethnic groups, and therefore could lower D. However, if the boundaries of the larger enumeration units are drawn to include only population of the same group, then D will not change significantly. Both the spatial autocorrelation of ethnic group population and zonal pattern are critical factors in determining the scale sensitivity of D. 相似文献
160.
David L. Wykes 《The Journal of religious history》1997,21(2):178-192
The 1689 Toleration Act allowed Protestant dissenters freedom to worship in public, but it was only a limited toleration and dissenters continued to suffer discrimination. This article examines the experience of Quakers in one important area, the Anglican monopoly in teaching. Although the prosecution of unlicensed teachers was patchy, localised, and dependent upon the hostility and zeal of particular individuals, few dissenters escaped harassment. Moreover, Friends appear to have suffered more severely because of the particular dislike that they still provoked and their unwillingness to compromise which often led to imprisonment. The growth in High Church feeling during Anne's reign led to a more rigorous enforcement of the existing statutes and the passing of the Schism Act (1714). The consequences of an Anglican educational monopoly have not been properly considered by historians largely from the assumption that the Schism Act was fatally compromised by the death of Queen Anne, and because little attention has been paid to the continued harassment of dissenters after toleration who attempted to teach. The Schism Act was repealed in 1719, but freedom for Quakers and other dissenters to teach had already been achieved largely through the courts. 相似文献