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The transitional agro‐ecological zone of Ghana, located between the richly endowed south and the impoverished north, has attracted seasonal and permanent farm migrants, mainly from northern Ghana, who now live side by side with the indigenous people. While migrants have higher numbers of Muslims, indigenous people are mainly Christians. Although the majority of the migrants live in migrant quarters with less favourable socio‐economic conditions, they are more successful farmers and therefore wealthier. The objectives are to examine the varying effect of fertility determinants among migrants and indigenous females. This paper uses data collected in 2002 among 194 females aged 15 to 49 years. Multiple regression models are used to assess fertility determinants. Results show that although migrant households were wealthier, migrant females were more traditional. They had more children living in foster care, and a lower proportion of them approved of men participating in household activities. In addition, they were less well educated, recorded higher infant mortality, gave birth earlier and used less contraception. Furthermore, while a female's migration status is statistically significant so far as non‐proximate determinants of fertility are concerned, the same variable is not significant with respect to proximate determinants. In addition, a married female migrant would on average have almost one more child compared to her indigenous counterpart, and migrant females who had experienced the loss of a child would on average have 2.5 more children compared to their indigenous counterparts. Finally, more affluent migrant females have 0.08 fewer children compared to their indigenous counterpart.  相似文献   
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A geophysical survey at the pyramid complex of Senwosret III at Dahshur sought to determine the suitability of magnetometry and electromagnetic induction (EMI, or conductivity) for mapping the area where several ancient boat-burials were found in the 1890s. At least one boat reported at the time of excavation remains unaccounted for. Tests demonstrated that magnetometry does detect subsurface structures of stone, fired brick, and unfired brick under current site conditions. Data indicated areas of geological activity as well as unexcavated archaeological remains, though no definitive traces of boat burials. No excavation was undertaken but another survey season is planned.
© 2009 The Authors  相似文献   
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Intensive agricultural systems interact strongly and reciprocally with features of the lands they occupy, and with features of the societies that they support. We modeled the distribution of two forms of pre-European contact intensive agriculture – irrigated pondfields and rain-fed dryland systems – across the Hawaiian archipelago using a GIS approach based on climate, hydrology, topography, substrate age, and soil fertility. Model results closely match the archaeological evidence in defined locations. On a broader scale, we calculate that the youngest island, Hawai'i, could have supported 572 km2 of intensive agriculture, 97% as rain-fed dryland field systems, while Kaua'i, the oldest island, could have supported 58 km2, all as irrigated wetland systems. Irrigated systems have higher, more reliable yields and lower labor requirements than rain-fed dryland systems, so the total potential yield from Kaua'i (49k metric tons) was almost half that of Hawai'i (97k metric tons), although Kaua'i systems required only 0.05 of the agricultural labor (8400 workers, versus 165,000 on Hawai'i) to produce the crops. We conclude that environmental constraints to intensive agriculture across the archipelago created asymmetric production efficiencies, and therefore varying potentials for agricultural surplus. The implications both for the emergence of complex sociopolitical formations and for anthropogenic transformation of Hawaiian ecosystems are substantial.  相似文献   
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