Lesson Notes By Weeks and Term v5 - Grade 11
Population ecology and human impact on the environment (Grade 11 focus) – Week 3 focus
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Population ecology and human impact on the environment (Grade 11 focus) – Week 3 focus
Download the Lessonotes Mobile South Africa app for faster lesson access on Android and iPhone.
Subject: Life Sciences
Class: Grade 11
Term: Term 4
Week: 3
Theme: General lesson support
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This week, we delve into the fascinating and critically important world of population ecology and how human actions profoundly impact our environment. Understanding population dynamics – how populations grow, shrink, and interact with their environment – is crucial for addressing some of the most pressing environmental challenges facing South Africa and the globe, such as resource depletion, habitat loss, and climate change. From understanding the impact of alien invasive species on our biodiversity to evaluating the sustainability of our resource use, population ecology provides the framework for informed decision-making and responsible environmental stewardship.
2.1 Population Ecology: Fundamentals Population ecology studies the dynamics of populations – groups of individuals of the same species living in the same area – and how they interact with their environment. Population size is constantly changing, influenced by four key factors: Birth Rate (Natality): The number of new individuals born into the population per unit of time.
Death Rate (Mortality): The number of individuals dying in the population per unit of time.
Immigration: The number of individuals entering the population from elsewhere.
Emigration: The number of individuals leaving the population to go elsewhere. The rate of population change can be calculated as: Population Change = (Births + Immigration) - (Deaths + Emigration) If the result is positive, the population is growing. If it's negative, the population is shrinking. If it is zero, the population size is stable.