Successions, Microbes and Cycles Ecology 3 Successions, Microbes and Cycles

Successions A succession is a series of steps that occur in an ecosystem over time Ecosystems use successions to respond to changes and damages from natural disasters or human activity. Terrestrial Successions: Occur on land Aquatic Successions: Occur in bodies of water

Successions

Terrestrial Successions There are 2 types of terrestrial successions: Primary Successions: Longer, and occur when there is no life, only bare rock Volcanic Eruptions New Island Formation Secondary Successions: Shorter, and occur when soil is present, but everything else is destroyed Wildfires Flood Bulldozer

Terrestrial Successions PRIMARY SECONDARY

Terrestrial Successions Pioneer Species is the first species to live on bare rock in a primary succession -Lichens and mosses Climax Community is the stable community of plants that develop over time in an ecosystem, it is the end result of succession

Terrestrial Successions

Aquatic Successions Aquatic Succession occurs when bodies of water eventually turn into land due to the buildup of sediment at the bottom of the water over time.

Microorganisms in Ecology Microorganisms are tiny living organisms that include bacteria, fungus, algae, protozoa, and viruses They tend to get a bad reputation, but most are actually very good for organisms and the environment. They are NOT ALL PATHOGENIC!

Microorganisms in Ecology Some examples of how microorganisms are beneficial include: Bacteria helping us digest food Bacteria and fungus that help decompose and recycle nutrients Bacteria that are modified to create insulin Fungus that can help break down oil after oil spills Bacteria help fix Nitrogen from the atmosphere so plants can use it

1) What role do microorganisms play in maintaining the health of organisms? E. Coli is bacteria found in the large intestines of humans. Helps get nutrients out of food that we can’t digest Produces some vitamins such as Vitamin K for blood clotting Lactobacilli is bacteria that helps in digesting milk proteins.

2) What role do microorganisms play in disrupting the health of organisms? Some microorganisms, such as bacteria and fungi, are pathogenic. This means they cause disease. Example: Streptococcus pyogenes causes Strep Throat.

3) What role do microorganisms play in maintaining the health of ecosystems? Bacteria and fungi are important in recycling nutrients. They are decomposers that chemically breakdown dead tissues into nutrients used by other organisms. Nitrogen Fixation is the process of turning atmospheric nitrogen into forms that can be absorbed and used by plants to produce proteins.

3) What role do microorganisms play in maintaining the health of ecosystems? Oil-Eating Bacteria help restore ecosystems after an oil spill. Mycorrhizal Fungi helps ecosystems recover following disturbances like forest fires or hurricanes.

4) What role do microorganisms play in disrupting the health of an ecosystem? Chestnut Blight Fungus – Accidentally introduced to US in 1900. Caused the death of Chestnut Trees throughout the eastern US, which provided nutrients to forest. Chestnut trees were replaced with oak, hickory and maple trees as a result. Red Tide – Some aquatic Euglena and dinoflagellates grow exponentially creating algal blooms that block out sunlight and reduce ocean oxygen levels. This causes fish and other sea organisms to die off suddenly.

Adaptations Organisms evolve and develop adaptations over time to help them survive in their specific environment Examples of some adaptations are: Migration/hibernation in cold environments Thick fur to stay warm Color changes to help camouflage based on environment Formation of plant spines instead of leaves to help conserve water

Carbon Cycle Carbon is the key ingredient for living things Human activity such as burning of oils/fuels as well as deforestation disrupt the carbon cycle causing an increase in greenhouse gases

Carbon Cycle Carbon is the key ingredient of living tissue. Carbon is present in the atmosphere as carbon dioxide (CO2). Carbon dioxide is released into the atmosphere by volcanic activity, by respiration, by human activities such as the burning of fossil fuels, and by decomposition of organic matter. Plants take in carbon dioxide and use the carbon to build carbohydrates during photosynthesis. The carbohydrates are passed along food webs to animals and other consumers, and the cycle continues.

Carbon Cycle What could happen if the carbon cycle is disrupted? Humans are disrupting the carbon cycle through the burning of fossil fuels. Burning fuels, like coal, oil, and natural gas, releases carbon dioxide into the upper atmosphere. The carbon dioxide is a greenhouse gas that acts like a blanket, trapping heat in our atmosphere. Clearing forests is also contributing to the build-up carbon dioxide, since trees remove carbon dioxide from the air, through photosynthesis.

Nitrogen Cycle Nitrogen is the most abundant gas in our atmosphere, it is a critical component for building proteins (primarily in plants)

Nitrogen Cycle Nitrogen is the most abundant gas in our atmosphere, but not many organisms can use nitrogen in that form. A few, special types of bacteria, known as “nitrogen-fixing bacteria,” can change nitrogen to a form that many organisms can use. These bacteria live in the soil, near the roots of plants. Lightning also has the ability to change nitrogen to a usable form.   Plants take the nitrogen (ammonia) from the soil to make proteins. Animals eat the plants to get the nitrogen they require. When plants and animals die, the organic material returns to the soil and atmosphere.

Nitrogen Cycle What could happen if the nitrogen cycle is disrupted? All organisms need nitrogen to build proteins. Disrupting the nitrogen cycle could have devastating effects – first affecting plants and their ability to make proteins.

Review PRIMARY SUCCESSION! Which type of succession would you expect to see after a volcanic eruption? PRIMARY SUCCESSION!

Review Which type of succession takes longer? PRIMARY SUCCESSION!

They turn into land which is called aquatic succession! Review What eventually happens to ponds over time? What is this called? They turn into land which is called aquatic succession!

Review Pioneer Species (lichen and moss) What is the first species that lives on bare rock called? Pioneer Species (lichen and moss)

The stable community of plants that form in an ecosystem over time Review What is a climax community? The stable community of plants that form in an ecosystem over time

Critical Write Describe how primary succession is related to life forming after the dinosaurs were destroyed.