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Potsherds from archaeological sites are usually found barren of palynomorphs. Recently half burnt potsherds from an excavation site dated to 3320 ± 400 years BP to 2080 ± 80 years BP in Gangetic West Bengal, India yielded some palynotaxa. That palynomorphs can remain preserved in half burnt potsherds was experimentally proved with pots made from mud mixed with known pollen grains and burning for variable duration. Pots burnt for shorter duration showed recovery, while prolonged firing showed poor/no recovery. Present study suggests the use of pollen grains from under-fired ancient potsherds as a reliable tool in deciphering vegetation, climate, agriculture and related parameters of archaeological research. 相似文献
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Saswata Ghosh 《Asian Population Studies》2017,13(1):25-49
Fertility transition occurred during the 1970s in Kolkata (erstwhile Calcutta), capital of the state of West Bengal, India, and has remained persistently at the low fertility level. Fertility rate in Kolkata attained its lowest-low level in the beginning of the present century. It currently has the lowest fertility rate (TFR 1.2) in India. This could be a case of second demographic transition (SDT) or pertains to changing dynamics in childbearing, childrearing, and/or aspirations for children. Using primary data of 600 couples (1200 individuals) and employing quantitative and qualitative methods, this study found that constraints in childbearing and childrearing; and aspirations for children have a strong negative and significant effect on second and higher order childbearing among couples, particularly among women. In our study there was no strong evidence of voluntary childlessness as well as decline in the importance of marriage, family and children as posited by SDT. Thus we argue that SDT might have to be redefined for a developing country context. 相似文献
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