Population Growth Concept Map

Transcription

1 Ecological Niche Definition: the way of life of a species, or its role in an ecological community Components: what it eats, where it lives, how it interacts with other species, etc

2 Population Growth Concept Map Exponential Logistic unlimited limited < < decrease increase > >

3 2 Types of Population Growth

4 Population Changes As time goes on, species A decreases. What are 2 possible reasons for the change? Species A was preyed on by Species B Species A had a lower birthrate Species A had a higher death rate (maybe a disease, etc.) Species A and B competed for the same resources As time goes on, species B increases. What are 2 possible reasons for the change? Species B preyed on Species C Species B had a higher birthrate Species A had a lower death rate (maybe a disease, etc.) Species A and B competed for the same resources

5 Population Change Look at Year 1-3, what letter does the graph look like? J In Year 1-3, the population was experiencing exponential growth because resources were unlimited. The population reached the carrying capacity of 250 individuals at Year 3 because competition increased.

6 U.S. Population Statistics From 1900 to 1990, as the birth rate decreased, the death rate decreased and the population increased. This is a inverse relationship. From 1900 to 1990, as the birth rate decreased, the life expectancy increased. This is a inverse relationship. From 1900 to 1990, as the death rate decreased, the life expectancy increased. This is a inverse relationship. From 1900 to 1990, as the life expectancy increased, the longevity increased. This is a direct relationship.

7 Ecological Succession Volcanic eruptions Glacial Retreats Forest fire Deforestation Farming Rock (no soil) Soil longer secondary succession primary shorter

8 Number of species Succession Graph (after abandonment of agricultural field) # of herb species # of shrub species # of tree species Years after abandonment of agricultural field

9 Succession Graph (after abandonment of agricultural field) What type of succession is occurring? Secondary succession The number of herb species decreased because there was less sunlight due to trees The number of shrub species increased because more sunlight and less competition The number of tree species increased because more sunlight and less competition

10 HIPPCO Threat to Biodiversity Habitat Loss Invasive Species Population Growth Description of the threat 1. Habitat Degradation loss of function 2. Habitat Destruction complete removal 3. Habitat Fragmentation split into parts - Due to development, mining, agriculture, etc. Native species usually present in that ecosystem Invasive species introduced and causing issues in ecosystem Human population has seen exponential growth, but growth is slowing so probably turning into logistic growth (approaching carrying capacity) Pollution 1. Land pollution toxic pollutants in landfills or in soil 2. Air pollution sulfur released from burning coal, turns into acid rain 3. Water pollution DDT in water and then moves up food chains Climate Change Humans are releasing more greenhouse gases from burning fossil fuels and raising livestock. This increases the amount of heat held in the atmosphere, warming our planet. How does it threaten biodiversity? What are effects of the threat? Wildlife cannot live without habitats they will move somewhere else or die out Invasive species do not have a natural predator and grow exponentially and cause the native species to disappear More humans mean more habitat loss and more pollution (including more greenhouse gases) Air pollution causes asthma and other breathing problems. CFCs cause ozone depletion. Causes health problems in humans and other animals. Loss of 20-50% of all species. Extreme weather. Rising sea levels. Melting of sea ice. Famine. Environmental Refugees. Overfishing Eating fish at a rate faster than they can reproduce Removes important species from the food chain.

11 DDT Which organism in the drawing has the highest concentration of DDT? The osprey, a predatory bird Based on the table, as the amount of DDT increases, the shell thickness decreases. Therefore, DDT affects birds by making their shells thin. How did the DDT get into the birds? The large birds ate fish. The DDT became more concentrated as you go up the food chain (bioaccumulation)