Ecosystems Limiting Factors

Ecological Hierarchy Biome Ecosystem Community Population Species Organism

Populations Biome Ecosystem Community Population Species Organism

Let’s suppose…. We have two mice…: and they produce the standard 56 “pups” (baby mice) each year. and each of these mice goes on to have 56 babies each year….

Soon….. We’d be over-run with mice on the planet!! Why doesn’t this occur?

Carrying Capacity What is Earth’s Current Population? ~ 7.1 Billion People How many humans can Earth support? 1 or 2 billion people living in prosperity, to 33 billion people fed on minimum rations and using all suitable land for high-intensity food production. Many scientists now believe that the human carrying capacity of Earth may be approximately 12 billion. What factors determine the Carry Capacity of Earth? Lifestyle, Food/Waste resources, Climate, Conflict… How many people can Earth support??

Limiting Factors A limiting factor is an abiotic or biotic factor that restricts the number of individuals in a population.

Limiting Factors Limiting factors can include: Competitors

Limiting Factors Limiting factors can include: Competitors Disease and parasites

Limiting Factors Limiting factors can include: Competitors Disease and parasites Weather

Limiting Factors Limiting factors can include: Competitors Disease and parasites Weather Fires

Limiting Factors Limiting factors can include: Competitors Disease and parasites Weather Fires Available habitat

Limiting Factors Limiting factors can include: Competitors Disease and parasites Weather Fires Available habitat Predators

Competitors-organisms both cooperate and compete Birds of prey Live in forests on the edge of fields Eat mice and other rodents Nest in trees Red-Tailed Hawk Barred Owl

Disease and Parasites Diseases and parasites can be dependent on population size and habitat

Weather Storms Drought Flooding Heat/cold

Fires Fires lead to succession which is a predictable change in the community over time.

Available Habitat Human activities play a large role Development, damming rivers, clear cutting forests.

Predators Predator-prey relationship can be a delicate balance between the two populations.

Predators As the prey population increases, the predator population increases. As the prey population decreases, then so does the predator population.

Example: Lynx and Hare:

Battle of Kruger