Unit 4 Section 4 - Ecosystems & Biotic Relationships

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  1. Ecosystem
  2. Abiotic
  3. Biotic
  4. Climate
  5. Weather
  6. Greenhouse effect 
  7. Earth's Heat
  8. Atmospheric pressure
  9. Surface water 
  10. Ground water
  1. Ecology
  2. Four laws of ecology
  3. Clouds
  4. Moisture
  5. Biomass
  6. Habitat
  7. Niche
  8. Tropic levels
  9. Food chain
  10. Food web
  1. Competition
  2. Symbiosis
  3. Ecological pyramid
  4. Population
  5. Carrying capacity
  6. Biotic potential
  7. Realized intrinsic rate of growth
include all the interacting parts of the environment in an area.

click to find the answer to today's question What is the greatest change humans have made to the Earth's environment?


Ecosystem components:       

Determining the characteristics of an ecosystem:

  • Abiotic components combine to define the environmental characteristics of the ecosystem.
  • Biotic components interact with each other to determine the success of life in the ecosystem.
  • Biotic components interact with abiotic components to determine the overall characteristics of the ecosystem.

Making a balanced ecosystem. link to an Internet Website    Cool!


Atmospheric Influences on ecosystems:

It is difficult to understand surfaces processes on the Earth without first knowing how the atmosphere influences these processes. There are four basic atmospheric components:

The science of Ecology link to an Internet Website

Ecology is the study of the interactions between organisms and the living and nonliving components of their environment. In other words, ecology is the study of ecosystems.

aquatic biomass pyramid Four Laws of Ecology:

  1. Everything is connected to everything else.
  2. Everything must go somewhere.
  3. Nature knows best.
  4. There is no such thing as a free lunch.

Ecology involves collecting information about organisms and their environment, looking for patterns, and seeking to explain these patterns. Over the past few decades, humans have changed the environment on a greater scale than ever before. The most significant environmental change is probably the rapid increase in the numbers of people on Earth. An increasing population requires increasing amounts of energy, food, and space for the disposal of waste. Providing for the needs of this growing population will take an increasingly greater share of Earth's resources.


Websites about our "local" ecosystem:


    Flora and Fauna of Arizona link to an Internet Website
    The Colorado plateau Ecosystem link to an Internet Website
    Middle Gila-Arizona Watershed link to an Internet Website
    Colorado Plateaus aquifer link to an Internet Website
    Water Resources in Arizona link to an Internet Website



Ecosystem Examples: are forest, rivers, meadows, soil, mountains, the surface waters of the ocean, the oceans' bottom, and the intertidal zone lying between the oceans and land.


4.4a Assignment - Ecosystems
Use the information above to answer the following questions.

  1. Within an ecosystem describe the difference between the abiotic factors and biotic factors?

  2. List a few example of abiotic and biotic factors within an ecosystem.

  3. Explain how the overall success and characteristics of a ecosystem is determined? Provide an example.

  4. What are the five basic atmospheric elements that influence the surface of our planet?

  5. What effects would low levels of carbon dioxide and water vapor in our atmosphere have on our planet?

  6. What are earth's three main climate zones?

  7. Why is an area of warm air called a low and and area of cold air called a high?

  8. Explain how the sun affects the wind?

  9. What is the difference between relative humidity and the dew point?

  10. How are weather and climate related?

  11. Cite evidence that shows two of the 4 laws of ecology at work.

  12. In your own words describe all the relationships that exist in one specific ecosystem (identify biotic & abiotic parts) ?

Honors biology: complete the above section along with this question


  1. Go further in-depth on questions 12 above and design a visual to answer the question.


Research Links:

Biology Class










An increase in the number of human beings and the stress that places on Earth's resources is the greatest change humans have made to the Earth's environment.