1. ECOSYSTEMS 1 WATER SOIL

2. Everything in the natural world is connected. An ecosystem is a community of living and non-living things that interact and work together in an area. Ecosystems have no particular size. An ecosystem can be as large as a desert or a lake or as small as a tree or a puddle. The water, water temperature, plants, animals, air, light and soil all work together. If there isn't enough light or water or if the soil doesn't have the right nutrients, the plants will die. If the plants die, animals that depend on them will die. If the animals that depend on the plants die, any animals that depend on those animals will die. All Ecosystems in nature work the same way. All the parts work together to make a balanced system! LIVING PARTS OF THE ECOSYSTEM NON-LIVING PARTS OF THE ECOSYSTEM 2

3. 3

4. Examples of some biotic factors: shrubs, grasses, fish, frogs, trees, cattails. 4

5. Examples of some abiotic factors: water, air, temperature, soil, rainfall, and sunlight Together, the abiotic factors make up the nonliving environment that surrounds plants and animals. 5

6. Populations  All members of one kind of organism that live in a particular area.  Some examples of a population may be all of the Elephants living on a Savannah, all rainbow trout in a stream, or all of the bald cypress trees in the swamp. 6 Living Things in an Ecosystem

7. Communities  All of the populations of organisms living in an ecosystem.  Example: all of the populations of rainbow trout, cacti plants, turtles, and microorganisms living in a pond ecosystem 7 Microorganisms are living things that are too small to be seen with just our eyes. Microorganisms make up part of a community.

8. LIMITING FACTORS

9. 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….

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

11. Limiting Factors The 4 main needs of an ecosystem: Food water Shelter Space An ecosystem only has a certain amount food, water, space, and shelter to support a certain number of organisms.

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

13. Limiting Factors Limiting factors can include: 1. Competitors 2. Disease and parasites 3. Predators

14. Limiting Factors Limiting factors can include: 1. Available Food 2. Available Water 3. Available Shelter 4. Available Space 5. Weather 6. Fires

15. Population changes Populations will rise and fall over long periods of time due to limiting factors. An increase or decrease in one population within an ecosystem affects the entire ecosystem. Example: There is a severe drought: Plant Populations Animal Populations

16. Population changes Human impact can dramatically limit and affect the survival of ecosystems. Example: Humans cut down trees in a forest, so there is less shelter, and food. Plant Populations Animal Populations

17. Predator and Prey As the prey population increases, the predator population increases. As the prey population decreases, then so does the predator population. Prey Population Predator Population Prey Population Predator Population