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Hellen JA 《GeoJournal》1981,5(4):369-384
Egypt's general population growth since 1805 is reviewed, with particular reference to the effect of changes in fertility and mortality since 1906 and factors affecting these variables. The rapidity of mortality decline is stressed and the nature of the epidemiological transition considered. In the light of population projections Egypt's population policies are described, and the diffusion of family planning since 1965 particularly is examined on a governorate basis. Finally, the success of the Population and Development Project set up in 1977 in instituting a radically new approach to family planning is presented. 相似文献
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Hellen Kezia Silva Almada Divino Vicente Silvério Marcia Nunes Macedo Leonardo Maracahipes-Santos Elizabete Carolina Pinheiro Zaratim Karina Pinheiro Zaratim 《水文科学杂志》2019,64(5):620-632
Water quality in streams is determined by several factors, including geology, topography, climate, and anthropogenic changes. This study aimed to assess the effects of watershed physical, morphology, and precipitation seasonality on the water quality of two streams that supply drinking water to rural settlements and urban areas in the Cerrado-Amazonia transition region. We monitored 16 physico-chemical attributes of water at six different sample locations over three years (2013–2016). Our results indicate that eight of these physico-chemical attributes did not meet the standards for safe drinking water established by Brazilian legislation. Precipitation seasonality, degradation of riparian zones, stream length, and watershed slope were the most important predictors of impaired water quality. Our results highlight the importance of restoring and conserving riparian forests in order to maintain drinking water quality. 相似文献
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