Presentation on theme: "Unit 4 Human Impact on the Environment. Population Three factors that affect population: –Number of births –Number of deaths –Number of individuals that."— Presentation transcript:
Limiting Factors A factor that causes population growth to decrease. Types of Factors: –Competition for resources –Nonrenewable and renewable –Predator – Prey –Disease –Climate Extremes
Non/renewable Resources Renewable resources can regenerate and therefore replaceable (not necessarily unlimited) –Trees, fresh water Nonrenewable cannot be replenish by natural processes –Coal, oil, natural gas (fossil fuels)
GREENHOUSE EFFECT Carbon dioxide-methane-water vapor and other atmosphere gases trap heat energy and maintain Earth’s temperature range. The natural situation in which heat is retained by this layer of greenhouse gases is called the greenhouse effect.
Acid Rain Burning of fossil fuels release gases, nitrogen oxide and sulfur dioxide, to combine with water vapor in the air Kill plants and leaves Dissolve and release toxins, like mercury from soil into biosphere
What is Biodiversity? A variety of living species in an ecosystem
Threats to Biodiversity Endangered Species Extinction Introducing a foreign species Pollution Biological Magnification
Endangered Species are a species population size that is declining in a way that places it in danger of extinction
Extinction – occurs when a species disappears from all or part of its range.
Invasive Species – species introduced into a non-native habitat (foreign species) Zebra Mussels Purple Loosestrife
Biomagnification Bioaccumulation: increase in concentration of a pollutant from the environment to the first organism in a food chain Biomagnification: increase in concentration of a pollutant from one link in a food chain to another
Conserving Biodiversity Conservation is the wise management of our natural resources including the preservation of habitats and wildlife
Biological Control Biological Control is using one species (hopefully native species) to control the population of another unwanted/harmful species Advantages – no need for pesticides (toxic chemicals) Disadvantages – no natural predator so it may overpopulate, disrupting food chain