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Azin A. L. Zeldi I. P. Smirnov A. V. Shagibalov R. Z. 《Russian Journal of Ecology》2001,32(3):216-219
The analysis of the demographic situation in the Republic of Mari El over ten years revealed the phenomenon of population aging with an increase in the number of elderly people. The phenomenon is regarded as an ecological indicator of the improvement of environmental quality; however, it poses some new problems in population gerontology. 相似文献
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