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In this article it is argued that conventional agro-ecological and organizational concepts used in pastoral development are strongly biased towards the formulation and enforcement of norms. This leads development experts to attempts to control pastoralists and their herds. The policies and development interventions based on these assumptions have been largely unsuccessful. As a consequence attention for dryland areas and pastoral development has declined among researchers and development agencies. An important reason for this failure is the fundamental misfit between these normative concepts and the reality of dryland ecosystems and pastoral society. In order to show this, an alternative view on rangeland ecology and pastoral society is presented, supported by a case study of Fulbe pastoral society in dryland Central Mali. The authors argue that approaches to pastoral development must be revised in the direction of the dynamics inherent in the pastoral way of life. 相似文献
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Testing for the Law of One Price and Identifying Price-Leading Markets: An Application to Corn Markets in Benin 总被引:1,自引:0,他引:1
A data-determined method is proposed to test for the law of one price as a long-run equilibrium condition and to identify which markets in a network of spatially dispersed commodity markets quote the reference price. The method consists of supplementing Johansen's FIML cointegration procedure with a permanent-transitory decomposition and rules of inference in linear time-series models with unit roots. As an example, we apply our method to prices of six corn markets in Benin. We find that the law of one price holds in the long-run. It appears that two rural markets quote the reference price: their prices adjust fastest towards the permanent change induced by the common stochastic trend. 相似文献
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Bea De Cupere An Lentacker Wim Van Neer Marc Waelkens Laurent Verslype 《International Journal of Osteoarchaeology》2000,10(4):254-267
Although the aetiology of bone pathologies in cattle is poorly documented, various deformations in the skeleton have been attributed to draught exploitation in the archaeozoological literature. This paper summarizes the results of an osteological study that was undertaken on the feet of modern draught oxen. This led to the definition of a series of draught‐related anomalies. In an attempt to describe the pathologies in a more consistent and quantitative way, a scoring scale for each individual bone pathology was established. The developed method is applied to cattle remains from four Roman and one late medieval site. The distribution of the observed pathological indices (PIs) on the first phalanges is interpreted in terms of the age structure of the cattle populations, and the possible modes of cattle exploitation and meat consumption in various settlement types. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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Lorraine Van Blerk 《Children's Geographies》2005,3(1):5-21
Previous geographical research with street children has principally focused on their micro-geographies in the city. This paper draws on nomadic and episodic processes of homeless mobility, to explore street children's geographies from a wider social, spatial and temporal perspective. By examining street life in Kampala, Uganda as a continued negotiation of public/private and street/non-street locations, the fluid nature of street children's identity is illustrated. Over time, movement between spaces, such as divergent city niches, institutions, homes and other towns, is often subject to power relations operating in street/non-street spaces with each requiring conformity to a different set of values and behaviours. The paper demonstrates how this results in children's street identity changing as they move through the street life path. 相似文献
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Overpressure in ‘old’ sedimentary basins that have not undergone rapid, recent sedimentation cannot be easily explained using traditional burial‐driven mechanisms. The last significant burial event in the Cooper Basin, Australia, was the Late Cretaceous deposition of the Winton Formation (98.5–90 Ma). Maximum temperature in the basin was attained during the Late Cretaceous, with cooling beginning prior to 75 Ma. Hence, overpressure related to rapid burial or palaeomaximum temperatures (e.g. hydrocarbon generation) must have developed prior to 75 Ma. Retaining overpressure for 75 Ma in ‘old’ basins such as the Cooper Basin requires extremely low seal permeabilities. An alternative explanation is that overpressure in the Cooper Basin has been generated because of an increase in mean stress associated with an increase in horizontal compressive stress since Late Cretaceous times. Structural observations and contemporary stress data indicate that there has been an increase in mean stress of approximately 50 MPa between Late Cretaceous times to that presently measured at 3780 m. The largest measured overpressure in the Cooper Basin is 14.5 MPa at 3780 m in the Kirby 1 well. Hence, disequilibrium compaction driven by increasing mean stress can explain the magnitude of the observed overpressure in the Cooper Basin. Increases in mean stress (tectonic loading) may be a feasible mechanism for overpressure generation in other ‘old’ basins that have undergone a recent increase in horizontal stress (e.g. Anadarko Basin). 相似文献
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The aim of the paper is to summarise the present state of knowledge concerning bitumen trade in the Near East from the Palaeolithic (70,000 BP) to the Early Islamic period. During the Palaeolithic and Early Neolithic period, bitumen utilisation was mostly concentrated in settlements close to oil seeps. From the Ubaid 3 period, bitumen from the Mosul area became more important and was traded as far as the southern Persian Gulf. The Uruk period is a turning point for Mesopotamian history as settlements evolved into city‐states. These cities had a great need for raw materials, and this marks the beginning of large‐scale exploitation of Hit bitumen. This bitumen was traded at settlements along the Euphrates, where a large trade network was established. Hit bitumen entered the Persian Gulf at the turn of the second millennium (Dilmun period). Bitumen from Iraq (Mosul and Hit) became predominantly used in most settlements along the southern coast of the Gulf. During this period Iranian bitumen was also exported and this supply tended to increase, especially during the Partho‐Sasanian period. Dead Sea bitumen had its own exchange network, which was concentrated across present‐day Israel and Egypt where it was extensively used for mummification. 相似文献