Ecology April 15th, 2009

Ecology Ecology is the study of the relationships among living organisms and their interactions with the physical environment. Biotic Factor – All the living and once living parts of an ecosystem, for example plants, animals, dead organisms, and waste. Abiotic Factor – The non-living and never living parts of an ecosystem, for example, air, water, rocks, sunlight, and temperature.

These relationships are in a constant state of flux (change), and even small changes can cause effects throughout the ecosystem. Reflect: List some of the biotic and abiotic factors that are in the picture to the right. Biotic – Abiotic –

Organisms and their environment are interdependent, meaning they depend on one another for survival. The butterfly in this picture could not survive without plants to eat and oxygen to breath, and plants could not grow unless bacteria and other organisms helped recycle nutrients and carbon dioxide into the water, soil, and air.

Think of ecology as changing relationships among the components of an ecosystem. Humans are participants in these ecosystem relationships, not just observers.

Look at the ecosystem above. How have humans changed this ecosystem?

Physical Environment Temperature Precipitation and Water Weather Rocks and Soil Atmosphere Natural Environment Trees and Plants Animals Determines the health of Is affected by Determines the productivity of Rely on Which affects Is affected by Humans Farming Industry Technology Pollution

Reflect: What non-living things in their environment do organisms interact with? In what ways are these non-living things essential to the organism? Using the flow chart above, explain how an increase in technology and industry (a seemingly good thing) might negatively affect humans in the long run.

Biodiversity Biodiversity refers to the collective variety of living organisms in an ecosystem.

Biodiversity is influenced by alterations in habitat, including but not limited to climate change, fire, flood, and invasion by organisms from another system.

The more biodiversity in an ecosystem, the greater its stability and resiliency (ability to bounce back from a disaster). More than half of the world's species of plants and animals are found in the rainforest.

Video – The Amazon Rain Forest

Reflect: What is the importance of Biodiversity? (Think back to what you learned in unit 5 about the importance of variation in a population.) A population of deer, mice, squirrels, and several species of birds and insects, live in a forest. How might a forest fire alter the biodiversity of this habitat? Humans have a negative affect on biodiversity. Strongly Agree, Agree, Disagree, or Strongly Disagree? Choose one and explain.

Agree or Disagree?? Look at the answer you chose for question #3 of your reflection. Look around the room. At each corner of the room there is a piece of paper that has one of the four choices on it: Strongly Agree, Agree, Disagree, or Strongly Disagree. Get up and go to the corner of the room that has the same paper as the answer you chose.

Exit Slip Answer the 3 multiple choice questions on the half sheet of paper. You have 3 minutes. Switch your paper with the person next to you. Put the number correct over 3, at the top of the paper and give it back to its owner. If you got any of the questions incorrect, explain the correct answer. You may ask your neighbor for help. Correct explanations get your ½ a point back. Make sure your name is on your paper and stack the papers neatly in the middle of your table.