Ecology- ecosytems and organisms ES.pptx

Ecosystems and organisms

1. Ecology: Ecosystems and Organisms

2. What is ECOLOGY? Ecology is a study of the connections in nature. How organisms(the biotic) interact with one another and with their nonliving(abiotic) environment. Living organisms can be studied at different levels of complexity

3. After watching the video s ummarize what the study of Ecology is and why it is important to know about?

4. Level of organization

5. Organisms and Species An organism is any unicellular or multicellular form exhibiting all of the characteristics of life, an individual. The lowest level of organization Organisms are classified into different species based on certain characteristics.

6. Biodiversity – is the number of species living together in an area. Population - A group of organisms of one species living in the same place at the same time that interbreed Produce fertile offspring Compete with each other for resources (food, mates, shelter, etc.) Community - several interacting populations that inhabit a common environment and are interdependent.

7. Use the word bank to label the diagram. Word Bank Population Organism Biosphere Community Ecosystem

8. Ecosystem All living organisms & nonliving environment in a certain geographical location. Examples are ponds, forests, grasslands, oceans, etc. Has biotic and abiotic factors. Biotic Factors -organisms in a habitat. Abiotic Factors – physical, nonliving things in habitat These biotic and abiotic components are linked together through nutrient cycles and energy flows.

9. Physical environment Community Biotic factors competitors symbionts predators parasites pathogens Ecosystem Abiotic factors atmosphere temperature soil water wind speed wind direction current velocity

10. Circle the biotic elements in an environment.

11. Abiotic factors affect living organisms in an ecosystem. How would these abiotic factors affect the living in an ecosystem? (pick at least 4 to explain) Fire Hurricanes Wind Frost Tornado Moisture Soil Air currents

12. Biotic factors affect the abiotic factors in an ecosystem. How would these biotic factors affect the abiotic factors in an ecosystem? Animal on side of road Algae and fungi on rocks

13. Habitat and Niche Habitat – place in which an organism lives out its life Niche – the role of a species in a community or ecosystem. A niche is determined by the tolerance limitations of an organism, or a limiting factor

14. Habitat Needs Cover – shelter; trees, shrubs, etc. Water Nutrients Macronutrients Chemicals organisms need in large numbers to live, grow, and reproduce. Ex. carbon, oxygen, hydrogen, nitrogen, calcium, and iron. Micronutrients These are needed in small or even trace amounts. Ex. sodium, zinc copper, chlorine, and iodine

15. Important Limiting Factors Food and water supply Population size Amount of Space Availability of mates Temperature Oxygen Sunlight Precipitation Wind Soil Any biotic or abiotic factor that restricts the existence of organisms in a specific environment is called a limiting factor. Examples of physical, and or chemical factors are: Fire frequency pH (acid/base) Latitude – distance from equator Altitude – distance above/below sea level

16. Law of Tolerance The law of tolerance states that “For each abiotic factor, an organism has a range of tolerances within which it can survive.” Tolerance range Optimum range Unavailable niche Marginal niche Number of organisms Preferred niche Marginal niche Unavailable niche Examples of abiotic factors that influence size of the realized niche Too acidic pH Too alkaline Too cold Temperature Too hot

17. Explain what the Law of Tolerance is and describe what’s happening in this image.

18. Limited Resources Limiting factors create environmental resistance to keep a populations numbers down so they don’t go over the carrying capacity .

19. Carrying capacity - maximum population of a particular species that a given habitat can support over time because of environmental resistance (limiting factors)

20. Carrying Capacity phase s A population that grows exponentially or too rapidly will overshoot the Carrying capacity. This is because of a reproductive time lag (the period required for the birth rate to fall & the death rate to rise). The population has a dieback or crashes and the carrying capacity is reached. If the population fluctuates at extremes above and below the carrying capacity, this unstable equilibrium can lead to a degraded carrying capacity as the available resources have been destroyed by the overgrown population. A more stable population results from logistic growth where the population aligns with the carrying capacity.

21. What are some limiting factors that would keep the human population from increasing?

22. Populations in Balance Populations always reach a size limit imposed by the factors of their environmental resistance such the shortage of water, space, and nutrients or by adverse conditions such as disease, drought and temperature extremes. Populations are always changing. Sometimes changes are the result of humans interfering with food webs or habitats. But even when humans do not interfere, populations will still naturally shift up and down or fluctuate as the availability of their resources change.

23. What is keeping these two populations in balance? Why is it important to keep populations in balance?