Biodiversity and ecosystem dynamics

Topic 4: Biodiversity and ecosystems

" Rainforests are Earth's oldest living ecosystems, with some surviving in their present form for at least 70 million years."

Please spend the next 5 minutes completing the ratings on varied words we will be learning throughout this topic

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​Vocabulary check

Can you explain the difference between heterotrophs and autotrophs?

Autotrophs

Otherwise known as producers

Heterotrophs

Known as consumers

This group of organisms obtains organic matter through the consumption of autotrophs and other heterotrophs (animals).

• Microorganisms consume the organic matter produced by the autotrophs

• Animals higher on the food chain consume the microorganisms and other animals and produce carbon dioxide through respiration.

Heterotrophs

Some are known as decomposers

Decomposers are organisms that break down dead or decaying organisms. They break down organic matter and convert it into inorganic matter which autotrophs feed off.

• Microscopic bacteria (E.coli)

• Fungi (Shitake Mushroom, Oyster Mushroom, Lion's mane)

• Protozoa

• and some invertebrate organisms

Resipration + Decomposition

The consumption of microorganisms and other animals causes the production of inorganic matter. This is then used by autotrophs and the process repeats itself.

Trophic energy levels

90% of energy is lost through trophic levels predominately as heat and the remaining is transferred through.

This is why there is an excess of primary producer species and fewer tertiary consumer species.

The difference between these two is that a chain just shows who eats who. Whereas, a web shows all the possible links between the different species through the trophic levels.

Food web vs food chain

Investigate

You are tasked to investigate a keystone species (an organism that helps define an entire ecosystem) and answer the following question:

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• Explain how the ecosystem would change if the keystone species were to rapidly become endangered or extinct.

  Be specific, I don't want the first basic answer you find :)

Match

Match the following

• Producer

• Consumer

• Decomposer

Produces organic matter from inorganic matter

Consumes organic matter and produces inorganic matter

Breaks down dead or decaying organisms

• Produces organic matter from inorganic matter

• Consumes organic matter and produces inorganic matter

• Breaks down dead or decaying organisms

Labelling

What does this diagram show?

Drag labels to their correct position on the image

Food web

Food link

Food chain

Food for thought

Open Ended

What percentage of energy is lost through each trophic level?

Multiple Choice

Can a consumer organism be contained to one trophic level?

• Yes

• No

• I need to learn more I have no idea.

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No organism occupies only one trophic level, as most consume plant and animal matter (omnivores). See the example above...

Trophic levels

Open Ended

​Based on the previous photo, can you tell me what the difference is between biotic and abiotic factors?

Biotic factors are living organisms in the ecosystem.

Decomposers

Producers

Consumers

Competitors/pathogens

​Biotic factors

Are non-living things in the ecosystem.

Water

Nutrients

Sunlight

Temperature

Abiotic factors

Abiotic and biotic factors

What is a niche?

A niche is a term described as an organism within a community that adapts to prevent the fight for resources to survive within an ecological community.

Biogeochemical cycles

The movement of nutrients between biotic and abiotic factors in the environment.

There are 4 cycles:

• Carbon

• Nitrogen

• Phosphorus

• Sulfur

​Task:

Choose one of the four biogeochemical cycles, and investigate and discuss how human activities such as the production of fertilizer affect your chosen cycle and the ecosystem.

Primary and secondary succession

This is where two or more organisms live together and one or both organisms benefit from one another.

For example sea anemone and clown fish.

​Symbiosis

Activity:

Research two different species and which symbiotic relationship those two species have and justify why.

• Mutualism

• Commensalism

• Parasitism

• Predation

Match

Match the following symbiotic relationships

• Mutualism

• Parasitism

• Commensalism

• Predation

Both species benefit

One species benefits the other is harmed

One species benefits and one is unaffected

One species benefits and the other is harmed

• Both species benefit

• One species benefits the other is harmed

• One species benefits and one is unaffected

• One species benefits and the other is harmed

Multiple Choice

Determine the mutualism relationship

• Bees and flowers

• Ticks and dogs

• Orcas and seals

• Hermit crabs and deceased snail shells

Competition within a single species. e.g. territorial behaviour or dominance.

Intraspecific

Competition between different species. e.g. predation or parasitism.

Interspecific

Interspecific vs intraspecific interactions

Activity: Concept map

• Use the whiteboard and a whiteboard marked to create a map of how all these words interact with one another in an ecosystem.

• On the arrows you draw connecting the words, I want you to write how they interact e.g. predator, energy source, photosynthesis.

(You can use your notes if you need).