Nurse Log Basics
What do we call a fallen tree that provides a home and nutrients for new plants to grow?
A Nurse Log.
True or False: Plants get the majority of the matter they need to grow from the soil.
False. (They get most matter from air and water).
This is the original source of energy for almost all life in the nurse log ecosystem.
The Sun.
These organisms, like fungi and bacteria, break down dead matter.
Decomposers.
A species that is not native to an area and causes harm is called this.
Invasive Species.
Name two things you might find living inside or under a nurse log.
(Any two) Salamanders, worms, beetles, moss, fungi, seedlings.
Plants use gas from the air and water to make food. Which gas do they take in?
Carbon Dioxide (CO2).
Plants are called "producers" because they turn light energy into ______ energy.
Chemical energy (sugar/food).
Decomposers are vital because they ______ nutrients back into the soil.
Recycle (or return).
If bullfrogs eat all the dragonflies in a pond, what happens to the animals that also rely on dragonflies for food?
They will struggle to survive or have to find new food sources (Competition).
How does a thick, solid tree trunk eventually become soft and "crumbly"?
Decomposers break down the wood fibers.
This scientific law states that matter cannot be created or destroyed, only changed.
The Law of Conservation of Matter.
When an animal eats a plant, what percentage of energy is typically passed on? (Hint: Most is used for heat/living).
Roughly 10% (The "10% Rule").
If you weigh a log and the decomposers on it, will the total weight increase, decrease, or stay the same over time?
Stay the same (Conservation of Matter).
What is one way humans can help restore balance to an ecosystem disrupted by an invasive species?
(Any one) Removing the invasive species, planting native plants, preventing transport of non-native pets.
Why do we call the nurse log a "system"?
Because it has interacting parts (living and non-living) that work together.
If a plant grows in a sealed jar, why doesn't the soil weight change much even as the plant gets heavy?
Because the plant's weight comes from the CO2 in the air, not the dirt.
Draw or describe a simple chain showing energy moving from the Sun to a Decomposer.
Sun to Plant to Animal to Decomposer.
How do decomposers get the energy they need to survive if they don't eat plants?
They get energy by breaking down the chemical bonds in dead matter.
Define "Carrying Capacity" in the context of a pond ecosystem.
The maximum number of individuals an environment can support without crashing.
What is the "Anchoring Phenomenon" of this entire 5.1 unit?
The fallen log (Nurse Log) in the Pacific Northwest.
What are the tiny, invisible building blocks that all matter (including air and logs) is made of?
Particles (or atoms/molecules).
Explain how energy from a dead animal eventually helps a new seedling grow on a nurse log.
Decomposers break down the animal and nutrients go to soil and seedling uses nutrients to grow.
Besides fungi, name a "microbe" that acts as a decomposer in the forest.
Bacteria.
If a scientist removes an invasive predator from a pond, explain why the population of primary producers (like algae or underwater plants) might actually decrease as a result.
This is due to a Trophic Cascade. Without the predator, the number of primary consumers (the animals that eat plants) will explode because nothing is hunting them. These extra consumers will then overgraze and eat up all the primary producers.