Demecology †the Ecology of Populations - 1574 Words

Topic 3: Demecology – the ecology of populations The main idea: Note how mathematical models are used to examine variation in growth of a population. Lecture outline: 1. Statistic and dynamic characteristics of population. 2. Growth curves patterns: J-shaped curve and S-shaped curve 3. Population regulation: Density-dependent and density-independent factors. 4. Human population patterns: - Population numbers. - Demographic transition and structure - Population urbanization 1. Statistic and dynamic characteristics of population Population – is a group of individuals of the same species that live in the same area. Population is an elementary and evolutionary unit of biosphere. Statistic characteristics: †¢Ã¢â‚¬ ¦show more content†¦Ã¢â‚¬ ¢ Density-independent factors –are factors that affect populations (reproduction and mortality rates) regardless of population density (natural disasters as forest fire, earthquake, flood etc.). 4. Human population patterns: †¢ Population numbers | |In 1650 ~ 500 million people. | |[pic] |In 2000 ~ 6 billion people. | | |In 2009 ~ 6.5 billion people. | | |This exponential growth rate can be explained by increase: | | |in food production | | |the rise of industry | | |advances in medicine | | |Growth rate is about 70 million people per year. It may be | | |limited by the same density-dependent factors that limit the |