# سكاني م 7.pdf

28 de May de 2023
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### سكاني م 7.pdf

• 1. Demographic Process: Population Growth 1 page (150- 157) Department Of Public Health. College of Applied Medical Sciences, Kamis Mushait. King Khalid University
• 2. Introduction Mortality and fertility have been examined separately the time has now come to look at how they act together to determine population growth. When consider the population, Pt, of a country at some time t, then the size of this population one year later, Pt + 1 is given by Where Bt and Dt are respectively the numbers of births and deaths occurring in the population between times t and t + I, and It and Et are respectively the numbers of immigrants and emigrants during the same period. ‫ﺗ‬ ‫م‬ ‫ﻓ‬ ‫ﺣ‬ ‫ص‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫ﺑ‬ ‫ﺷ‬ ‫ﻛ‬ ‫ل‬ ‫ﻣ‬ ‫ﻧ‬ ‫ﻔ‬ ‫ﺻ‬ ‫ل‬ ، ‫و‬ ‫ﻗ‬ ‫د‬ ‫ﺣ‬ ‫ﺎ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻗ‬ ‫ت‬ ‫ا‬ ‫ﻵ‬ ‫ن‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ظ‬ ‫ر‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻛ‬ ‫ﯾ‬ ‫ﻔ‬ ‫ﯾ‬ ‫ﺔ‬ ‫ﻋ‬ ‫ﻣ‬ ‫ﻠ‬ ‫ﮭ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻣ‬ ‫ﻌ‬ ً ‫ﺎ‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﺣ‬ ‫د‬ ‫ﯾ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ . ‫ﻋ‬ ‫ﻧ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ظ‬ ‫ر‬ ‫إ‬ ‫ﻟ‬ ‫ﻰ‬ ‫ﻋ‬ ‫د‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ، Pt ، ‫ﻟ‬ ‫ﺑ‬ ‫ﻠ‬ ‫د‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ‫و‬ ‫ﻗ‬ ‫ت‬ ‫ﻣ‬ ‫ﺎ‬ t ، ‫ﺛ‬ ‫م‬ ‫ﺣ‬ ‫ﺟ‬ ‫م‬ ‫ھ‬ ‫ذ‬ ‫ا‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﺑ‬ ‫ﻌ‬ ‫د‬ ‫ﻋ‬ ‫ﺎ‬ ‫م‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ، Pt + 1 ‫ﺑ‬ ‫و‬ ‫ا‬ ‫ﺳ‬ ‫ط‬ ‫ﺔ‬ ‫ﺣ‬ ‫ﯾ‬ ‫ث‬ Bt ‫و‬ Dt ‫ھ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﻲ‬ ‫ﻋ‬ ‫د‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﯾ‬ ‫د‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻲ‬ ‫ﺗ‬ ‫ﺣ‬ ‫د‬ ‫ث‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﺑ‬ ‫ﯾ‬ ‫ن‬ ‫ا‬ ‫ﻷ‬ ‫و‬ ‫ﻗ‬ ‫ﺎ‬ ‫ت‬ t ‫و‬ t + I ، ‫و‬ It ‫و‬ Et ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﻲ‬ ‫ﻋ‬ ‫د‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﺟ‬ ‫ر‬ ‫ﯾ‬ ‫ن‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﺟ‬ ‫ر‬ ‫ﯾ‬ ‫ن‬ ‫ﺧ‬ ‫ﻼ‬ ‫ل‬ ‫ﻧ‬ ‫ﻔ‬ ‫س‬ ‫ا‬ ‫ﻟ‬ ‫ﻔ‬ ‫ﺗ‬ ‫ر‬ ‫ة‬ . 2
• 3. Fertility and population growth In Section8 .5, a measure known as the total fertility rate (TFR) was introduced. The TFR is obtained by summing the age-specific fertility rates( ASFRs) over the ages from 15 to 49 years last birthday. ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﻘ‬ ‫ﺳ‬ ‫م‬ 8 . 5 ، ‫ﺗ‬ ‫م‬ ‫إ‬ ‫د‬ ‫ﺧ‬ ‫ﺎ‬ ‫ل‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫س‬ ‫ﯾ‬ ‫ﻌ‬ ‫ر‬ ‫ف‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﺳ‬ ‫م‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫ا‬ ‫ﻹ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ) TFR). ‫ﯾ‬ ‫ﺗ‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺣ‬ ‫ﺻ‬ ‫و‬ ‫ل‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫ا‬ ‫ﻹ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ‫ﻣ‬ ‫ن‬ ‫ﺧ‬ ‫ﻼ‬ ‫ل‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﻊ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ﻻ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺎ‬ ‫ﺻ‬ ‫ﺔ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻌ‬ ‫ﻣ‬ ‫ر‬ ) ASFRs) ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻣ‬ ‫د‬ ‫ى‬ ‫ا‬ ‫ﻷ‬ ‫ﻋ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ر‬ ‫ﻣ‬ ‫ن‬ 15 ‫إ‬ ‫ﻟ‬ ‫ﻰ‬ 49 ‫ﻋ‬ ‫ﺎ‬ ‫ﻣ‬ ً ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻋ‬ ‫ﯾ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﯾ‬ ‫ﻼ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﺿ‬ ‫ﻲ‬ . Population growth depends much more on the number of girls that are born than on the number of boys. Thus the sex ratio of births is important. The sex ratio of births is taken into account by the gross reproduction rate (GRR). ‫ﯾ‬ ‫ﻌ‬ ‫ﺗ‬ ‫ﻣ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻋ‬ ‫د‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﻔ‬ ‫ﺗ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﻼ‬ ‫ﺋ‬ ‫ﻲ‬ ‫ﯾ‬ ‫و‬ ‫ﻟ‬ ‫د‬ ‫ن‬ ‫أ‬ ‫ﻛ‬ ‫ﺛ‬ ‫ر‬ ‫ﻣ‬ ‫ن‬ ‫ا‬ ‫ﻋ‬ ‫ﺗ‬ ‫ﻣ‬ ‫ﺎ‬ ‫د‬ ‫ه‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻋ‬ ‫د‬ ‫د‬ ‫ا‬ ‫ﻷ‬ ‫و‬ ‫ﻻ‬ ‫د‬ . ‫و‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ‫ﻓ‬ ‫ﺈ‬ ‫ن‬ ‫ﻧ‬ ‫ﺳ‬ ‫ﺑ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﯾ‬ ‫د‬ ‫ﺑ‬ ‫ﯾ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ﺟ‬ ‫ﻧ‬ ‫ﺳ‬ ‫ﯾ‬ ‫ن‬ ‫ﻣ‬ ‫ﮭ‬ ‫ﻣ‬ ‫ﺔ‬ . ‫ﺗ‬ ‫ؤ‬ ‫ﺧ‬ ‫ذ‬ ‫ﻧ‬ ‫ﺳ‬ ‫ﺑ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﯾ‬ ‫د‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻻ‬ ‫ﻋ‬ ‫ﺗ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ر‬ ‫ﻣ‬ ‫ن‬ ‫ﺧ‬ ‫ﻼ‬ ‫ل‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻹ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ) GRR). 3
• 4. Some of the children born will not survive to have children themselves we know that age specific death rates in infancy and childhood are quite high, especially in developing. Children who die in infancy will not contribute to the growth of the population in the long run, since they will have no children themselves. ‫ﻟ‬ ‫ن‬ ‫ﯾ‬ ‫ﺗ‬ ‫ﻣ‬ ‫ﻛ‬ ‫ن‬ ‫ﺑ‬ ‫ﻌ‬ ‫ض‬ ‫ا‬ ‫ﻷ‬ ‫ط‬ ‫ﻔ‬ ‫ﺎ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫و‬ ‫ﻟ‬ ‫و‬ ‫د‬ ‫ﯾ‬ ‫ن‬ ‫ﻣ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ﺑ‬ ‫ﻘ‬ ‫ﺎ‬ ‫ء‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻗ‬ ‫ﯾ‬ ‫د‬ ‫ا‬ ‫ﻟ‬ ‫ﺣ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ة‬ ‫ﻹ‬ ‫ﻧ‬ ‫ﺟ‬ ‫ﺎ‬ ‫ب‬ ‫ا‬ ‫ﻷ‬ ‫ط‬ ‫ﻔ‬ ‫ﺎ‬ ‫ل‬ ‫ﺑ‬ ‫ﺄ‬ ‫ﻧ‬ ‫ﻔ‬ ‫ﺳ‬ ‫ﮭ‬ ‫م‬ ، ‫ﻓ‬ ‫ﻧ‬ ‫ﺣ‬ ‫ن‬ ‫ﻧ‬ ‫ﻌ‬ ‫ﻠ‬ ‫م‬ ‫أ‬ ‫ن‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ﻻ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺎ‬ ‫ﺻ‬ ‫ﺔ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻌ‬ ‫ﻣ‬ ‫ر‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻣ‬ ‫ر‬ ‫ﺣ‬ ‫ﻠ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ر‬ ‫ﺿ‬ ‫ﺎ‬ ‫ﻋ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ط‬ ‫ﻔ‬ ‫و‬ ‫ﻟ‬ ‫ﺔ‬ ‫ﻣ‬ ‫ر‬ ‫ﺗ‬ ‫ﻔ‬ ‫ﻌ‬ ‫ﺔ‬ ‫ﺟ‬ ‫د‬ ً‫ا‬ ، ‫ﻻ‬ ‫ﺳ‬ ‫ﯾ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻣ‬ ‫ر‬ ‫ﺣ‬ ‫ﻠ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ . ‫ﻟ‬ ‫ن‬ ‫ﯾ‬ ‫ﺳ‬ ‫ﺎ‬ ‫ھ‬ ‫م‬ ‫ا‬ ‫ﻷ‬ ‫ط‬ ‫ﻔ‬ ‫ﺎ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ذ‬ ‫ﯾ‬ ‫ن‬ ‫ﯾ‬ ‫ﻣ‬ ‫و‬ ‫ﺗ‬ ‫و‬ ‫ن‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﺳ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ر‬ ‫ﺿ‬ ‫ﺎ‬ ‫ﻋ‬ ‫ﺔ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫د‬ ‫ى‬ ‫ا‬ ‫ﻟ‬ ‫ط‬ ‫و‬ ‫ﯾ‬ ‫ل‬ ، ‫ﻷ‬ ‫ﻧ‬ ‫ﮭ‬ ‫م‬ ‫ﻟ‬ ‫ن‬ ‫ﯾ‬ ‫ﻧ‬ ‫ﺟ‬ ‫ﺑ‬ ‫و‬ ‫ا‬ ‫أ‬ ‫ط‬ ‫ﻔ‬ ‫ﺎ‬ ‫ﻻ‬ ً . 4
• 5. The net reproduction rate The net reproduction rate (NRR) is simply the gross reproduction rate adjusted for mortality. It is a most important measure of the rate of population growth. ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﺻ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ) NRR) ‫ھ‬ ‫و‬ ‫ﺑ‬ ‫ﺑ‬ ‫ﺳ‬ ‫ﺎ‬ ‫ط‬ ‫ﺔ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻹ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ﻟ‬ ‫ﻠ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ . ‫إ‬ ‫ﻧ‬ ‫ﮫ‬ ‫أ‬ ‫ھ‬ ‫م‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫س‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ . 5
• 6. DATA FOR CALCULATING THE NET REPRODUCTION RATE 6 As we have defined it, the NRR is a cohort measure of population growth. Of course, we could calculate it using fertility and mortality data for a single calendar year (or for a particular period). The NRR calculated using data for a single calendar year will only be a good measure of the long-run growth of a population if the fertility and mortality rates for that calendar year are maintained for a long period of time. ‫ﻛ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﺣ‬ ‫د‬ ‫د‬ ‫ﻧ‬ ‫ﺎ‬ ‫ھ‬ ‫ﺎ‬ ، ‫ﻓ‬ ‫ﺈ‬ ‫ن‬ NRR ‫ھ‬ ‫و‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫س‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻋ‬ ‫ﻲ‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ . ‫ﺑ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ط‬ ‫ﺑ‬ ‫ﻊ‬ ، ‫ﯾ‬ ‫ﻣ‬ ‫ﻛ‬ ‫ﻧ‬ ‫ﻧ‬ ‫ﺎ‬ ‫ﺣ‬ ‫ﺳ‬ ‫ﺎ‬ ‫ﺑ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﺳ‬ ‫ﺗ‬ ‫ﺧ‬ ‫د‬ ‫ا‬ ‫م‬ ‫ﺑ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﺎ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫ﺔ‬ ‫ﺗ‬ ‫ﻘ‬ ‫و‬ ‫ﯾ‬ ‫ﻣ‬ ‫ﯾ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ‫ة‬ ) ‫أ‬ ‫و‬ ‫ﻟ‬ ‫ﻔ‬ ‫ﺗ‬ ‫ر‬ ‫ة‬ ‫ﻣ‬ ‫ﻌ‬ ‫ﯾ‬ ‫ﻧ‬ ‫ﺔ‬ ( . ‫ﺳ‬ ‫ﯾ‬ ‫ﻛ‬ ‫و‬ ‫ن‬ NRR ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﺣ‬ ‫ﺳ‬ ‫و‬ ‫ب‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﺳ‬ ‫ﺗ‬ ‫ﺧ‬ ‫د‬ ‫ا‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺑ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﺎ‬ ‫ت‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫ﺔ‬ ‫ﺗ‬ ‫ﻘ‬ ‫و‬ ‫ﯾ‬ ‫ﻣ‬ ‫ﯾ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ‫ة‬ ‫ﻓ‬ ‫ﻘ‬ ‫ط‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ﺳ‬ ً ‫ﺎ‬ ‫ﺟ‬ ‫ﯾ‬ ‫د‬ ً‫ا‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ط‬ ‫و‬ ‫ﯾ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫د‬ ‫ى‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫إ‬ ‫ذ‬ ‫ا‬ ‫ﺗ‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺣ‬ ‫ﻔ‬ ‫ﺎ‬ ‫ظ‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ﻻ‬ ‫ت‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻠ‬ ‫ك‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻘ‬ ‫و‬ ‫ﯾ‬ ‫ﻣ‬ ‫ﯾ‬ ‫ﺔ‬ ‫ﻟ‬ ‫ﻔ‬ ‫ﺗ‬ ‫ر‬ ‫ة‬ ‫ط‬ ‫و‬ ‫ﯾ‬ ‫ﻠ‬ ‫ﺔ‬ ‫ﻣ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ز‬ ‫ﻣ‬ ‫ن‬ .
• 7. Geometric and exponential growth 7 We have now introduced one measure of population growth, the net reproduction rate. In this section, we consider population growth more abstractly. We look at two models of population growth. GEOMETRIC GROWTH: Consider a population at some point in time, and suppose that its size at that time is Po· Suppose that its size one year later is Pi The absolute change in the population size during the year is equal to Pi - Po, and the rate of change, which we shall denote by the symbol r, is defined by the equation. ‫ﻟ‬ ‫ﻘ‬ ‫د‬ ‫أ‬ ‫د‬ ‫ﺧ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﺎ‬ ‫ا‬ ‫ﻵ‬ ‫ن‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ﺳ‬ ً ‫ﺎ‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ً‫ا‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ، ‫و‬ ‫ھ‬ ‫و‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﺻ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ . ‫ﻓ‬ ‫ﻲ‬ ‫ھ‬ ‫ذ‬ ‫ا‬ ‫ا‬ ‫ﻟ‬ ‫ﻘ‬ ‫ﺳ‬ ‫م‬ ، ‫ﻧ‬ ‫ﻌ‬ ‫ﺗ‬ ‫ﺑ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ‫أ‬ ‫ﻛ‬ ‫ﺛ‬ ‫ر‬ ‫ﺗ‬ ‫ﺟ‬ ‫ر‬ ‫ﯾ‬ ‫د‬ ً‫ا‬ . ‫ﻧ‬ ‫ﺣ‬ ‫ن‬ ‫ﻧ‬ ‫ﻧ‬ ‫ظ‬ ‫ر‬ ‫إ‬ ‫ﻟ‬ ‫ﻰ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ذ‬ ‫ﺟ‬ ‫ﯾ‬ ‫ن‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ . ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﮭ‬ ‫ﻧ‬ ‫د‬ ‫ﺳ‬ ‫ﻲ‬ : ‫ﺿ‬ ‫ﻊ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻋ‬ ‫ﺗ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ر‬ ‫ك‬ ‫ﻣ‬ ‫ﺟ‬ ‫ﻣ‬ ‫و‬ ‫ﻋ‬ ‫ﺔ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﯾ‬ ‫ﺔ‬ ‫ﻓ‬ ‫ﻲ‬ ‫و‬ ‫ﻗ‬ ‫ت‬ ‫ﻣ‬ ‫ﺎ‬ ، ‫و‬ ‫ا‬ ‫ﻓ‬ ‫ﺗ‬ ‫ر‬ ‫ض‬ ‫أ‬ ‫ن‬ ‫ﺣ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ذ‬ ‫ﻟ‬ ‫ك‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻗ‬ ‫ت‬ ‫ھ‬ ‫و‬ Po. ‫ا‬ ‫ﻓ‬ ‫ﺗ‬ ‫ر‬ ‫ض‬ ‫أ‬ ‫ن‬ ‫ﺣ‬ ‫ﺟ‬ ‫ﻣ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﺑ‬ ‫ﻌ‬ ‫د‬ ‫ﻋ‬ ‫ﺎ‬ ‫م‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ‫ھ‬ ‫و‬ Pi. ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻐ‬ ‫ﯾ‬ ‫ﯾ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ط‬ ‫ﻠ‬ ‫ق‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﺣ‬ ‫ﺟ‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﺧ‬ ‫ﻼ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻌ‬ ‫ﺎ‬ ‫م‬ ‫ﯾ‬ ‫ﺳ‬ ‫ﺎ‬ ‫و‬ ‫ي‬ Pi-Po ، ‫و‬ ‫ﯾ‬ ‫ﺗ‬ ‫م‬ ‫ﺗ‬ ‫ﺣ‬ ‫د‬ ‫ﯾ‬ ‫د‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻐ‬ ‫ﯾ‬ ‫ﯾ‬ ‫ر‬ ، ‫ا‬ ‫ﻟ‬ ‫ذ‬ ‫ي‬ ‫ﻧ‬ ‫ﺷ‬ ‫ﯾ‬ ‫ر‬ ‫إ‬ ‫ﻟ‬ ‫ﯾ‬ ‫ﮫ‬ ‫ﺑ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ر‬ ‫ﻣ‬ ‫ز‬ r ، ‫ﺑ‬ ‫و‬ ‫ا‬ ‫ﺳ‬ ‫ط‬ ‫ﺔ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫ﺎ‬ ‫د‬ ‫ﻟ‬ ‫ﺔ‬ .
• 9. EXPONENTIAL GROWTH: It may be thought that geometric growth is quite a good description of how populations grow. The geometric growth model in equation (12.3) assumes that the population change in each year, which involves people either being added to the population or taken away, happens at a single point in time. ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﮭ‬ ‫ﺎ‬ ‫ﺋ‬ ‫ل‬ : ‫ﻗ‬ ‫د‬ ‫ﯾ‬ ُ ‫ﻌ‬ ‫ﺗ‬ ‫ﻘ‬ ‫د‬ ‫أ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﮭ‬ ‫ﻧ‬ ‫د‬ ‫ﺳ‬ ‫ﻲ‬ ‫ھ‬ ‫و‬ ‫و‬ ‫ﺻ‬ ‫ف‬ ‫ﺟ‬ ‫ﯾ‬ ‫د‬ ‫ﻟ‬ ‫ﻛ‬ ‫ﯾ‬ ‫ﻔ‬ ‫ﯾ‬ ‫ﺔ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ . ‫ﯾ‬ ‫ﻔ‬ ‫ﺗ‬ ‫ر‬ ‫ض‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ذ‬ ‫ج‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﮭ‬ ‫ﻧ‬ ‫د‬ ‫ﺳ‬ ‫ﻲ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫ﺎ‬ ‫د‬ ‫ﻟ‬ ‫ﺔ‬ ) 12.3 ( ‫أ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻐ‬ ‫ﯾ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻛ‬ ‫ل‬ ‫ﻋ‬ ‫ﺎ‬ ‫م‬ ، ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ذ‬ ‫ي‬ ‫ﯾ‬ ‫ﺗ‬ ‫ﺿ‬ ‫ﻣ‬ ‫ن‬ ‫إ‬ ‫ﻣ‬ ‫ﺎ‬ ‫إ‬ ‫ﺿ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﺔ‬ ‫ا‬ ‫ﻷ‬ ‫ﺷ‬ ‫ﺧ‬ ‫ﺎ‬ ‫ص‬ ‫إ‬ ‫ﻟ‬ ‫ﻰ‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫أ‬ ‫و‬ ‫ا‬ ‫ﺳ‬ ‫ﺗ‬ ‫ﺑ‬ ‫ﻌ‬ ‫ﺎ‬ ‫د‬ ‫ھ‬ ‫م‬ ، ‫ﯾ‬ ‫ﺣ‬ ‫د‬ ‫ث‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻧ‬ ‫ﻘ‬ ‫ط‬ ‫ﺔ‬ ‫ز‬ ‫ﻣ‬ ‫ﻧ‬ ‫ﯾ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﺣ‬ ‫د‬ ‫ة‬ . 9
• 10. 10
• 11. 11
• 12. 12
• 13. 13
• 14. The annual rate of growth and the net reproduction rate The equation( 12.7) says nothing about fertility and mortality. It simply describes a rather abstract growth model. However, we can link the annual rate of population growth to the net reproduction rate. Recall that the NRR is a measure of the population size in the next generation divided by the population size in the present generation all we need to link the NRR to the annual rate of growth is to know how long a generation is . ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫و‬ ‫ي‬ ‫و‬ ‫ﺻ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫ﺎ‬ ‫د‬ ‫ﻟ‬ ‫ﺔ‬ ) 12.7 ( ‫ﻻ‬ ‫ﺗ‬ ‫ﻘ‬ ‫و‬ ‫ل‬ ‫ﺷ‬ ‫ﯾ‬ ‫ﺋ‬ ً‫ﺎ‬ ‫ﻋ‬ ‫ن‬ ‫ا‬ ‫ﻟ‬ ‫ﺧ‬ ‫ﺻ‬ ‫و‬ ‫ﺑ‬ ‫ﺔ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫و‬ ‫ﻓ‬ ‫ﯾ‬ ‫ﺎ‬ ‫ت‬ . ‫إ‬ ‫ﻧ‬ ‫ﮫ‬ ‫ﯾ‬ ‫ﺻ‬ ‫ف‬ ‫ﺑ‬ ‫ﺑ‬ ‫ﺳ‬ ‫ﺎ‬ ‫ط‬ ‫ﺔ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ذ‬ ‫ج‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ﻣ‬ ‫ﺟ‬ ‫ر‬ ‫د‬ ‫إ‬ ‫ﻟ‬ ‫ﻰ‬ ‫ﺣ‬ ‫د‬ ‫ﻣ‬ ‫ﺎ‬ . ‫و‬ ‫ﻣ‬ ‫ﻊ‬ ‫ذ‬ ‫ﻟ‬ ‫ك‬ ، ‫ﯾ‬ ‫ﻣ‬ ‫ﻛ‬ ‫ﻧ‬ ‫ﻧ‬ ‫ﺎ‬ ‫ر‬ ‫ﺑ‬ ‫ط‬ ‫ا‬ ‫ﻟ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫و‬ ‫ي‬ ‫ﻟ‬ ‫ﻠ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﻲ‬ ‫ﺑ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ﺛ‬ ‫ر‬ ‫ا‬ ‫ﻟ‬ ‫ﺻ‬ ‫ﺎ‬ ‫ﻓ‬ ‫ﻲ‬ . ‫ﺗ‬ ‫ذ‬ ‫ﻛ‬ ‫ر‬ ‫أ‬ ‫ن‬ NRR ‫ھ‬ ‫و‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﯾ‬ ‫ﺎ‬ ‫س‬ ‫ﻟ‬ ‫ﺣ‬ ‫ﺟ‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﺟ‬ ‫ﯾ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺗ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ‫ﻣ‬ ‫ﻘ‬ ‫ﺳ‬ ‫و‬ ‫ﻣ‬ ً ‫ﺎ‬ ‫ﻋ‬ ‫ﻠ‬ ‫ﻰ‬ ‫ﺣ‬ ‫ﺟ‬ ‫م‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻛ‬ ‫ﺎ‬ ‫ن‬ ‫ﻓ‬ ‫ﻲ‬ ‫ا‬ ‫ﻟ‬ ‫ﺟ‬ ‫ﯾ‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺣ‬ ‫ﺎ‬ ‫ﻟ‬ ‫ﻲ‬ ، ‫ﻛ‬ ‫ل‬ ‫ﻣ‬ ‫ﺎ‬ ‫ﻧ‬ ‫ﺣ‬ ‫ﺗ‬ ‫ﺎ‬ ‫ﺟ‬ ‫ﮫ‬ ‫ﻟ‬ ‫ر‬ ‫ﺑ‬ ‫ط‬ NRR ‫ﺑ‬ ‫ﻣ‬ ‫ﻌ‬ ‫د‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﻧ‬ ‫ﻣ‬ ‫و‬ ‫ا‬ ‫ﻟ‬ ‫ﺳ‬ ‫ﻧ‬ ‫و‬ ‫ي‬ ‫ھ‬ ‫و‬ ‫ﻣ‬ ‫ﻌ‬ ‫ر‬ ‫ﻓ‬ ‫ﺔ‬ ‫ط‬ ‫و‬ ‫ل‬ ‫ا‬ ‫ﻟ‬ ‫ﺟ‬ ‫ﯾ‬ ‫ل‬ . 14
• 15. 15