THE CARBON CYCLE
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Let's start learning about the carbon cycle by creating our own closed environment.
What is the Carbon Cycle?
The carbon cycle is the continuous, natural process by which carbon atoms travel between the atmosphere, Earth's surface (rocks/soil), oceans, and living organisms. It is essential for life, balancing carbon storage and release through fast (photosynthesis/respiration) and slow (geological storage) processes.
How is the Earth's Carbon Cycle similar to a Closed Terrarium?
In the Earth's atmosphere, matter cycles instead of disappearing. Atoms and molecules have been reused for as long as there has been matter. Through the water cycle, water falls to earth, evaporates, turns into clouds, and finally falls to Earth again. Between falling and evaporating, water can be drunk by an animal; make watermelon juicy; become part of a fish; and much more.
The Carbon cycle shows us how we reuse this element; through photosynthesis, plants remove some Carbon dioxide from the atmosphere, breaking CO2 molecules to create carbohydrates like glucose, fructose and sucrose. When animals eat plants, sugars are broken down to create energy, releasing CO2 as byproduct into the atmosphere; or added to living tissue, later released when they die, with help from bacteria and detritivores, adding carbon back to Earth.
A balanced closed terrarium works the same way. The lid isolates the system from the outside, creating both a carbon and a water cycle, like the ones on Earth. The bugs and bacteria eat decaying matter, releasing the carbon back to the earth as well as the air inside the jar.
The Carbon cycle shows us how we reuse this element; through photosynthesis, plants remove some Carbon dioxide from the atmosphere, breaking CO2 molecules to create carbohydrates like glucose, fructose and sucrose. When animals eat plants, sugars are broken down to create energy, releasing CO2 as byproduct into the atmosphere; or added to living tissue, later released when they die, with help from bacteria and detritivores, adding carbon back to Earth.
A balanced closed terrarium works the same way. The lid isolates the system from the outside, creating both a carbon and a water cycle, like the ones on Earth. The bugs and bacteria eat decaying matter, releasing the carbon back to the earth as well as the air inside the jar.
Did You Know?Plants don't just do photosynthesis; they also perform cellular respiration just like us. At night, when there is no light, plants use the oxygen in the jar to break down their stored sugars for energy, releasing CO2 back into the air.
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Did You Know?While the terrarium is a closed system for matter (nothing enters or leaves), it is an open system for energy. Sunlight enters through the glass to power photosynthesis, and heat eventually radiates back out.
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Did you know? |
Did you know? |
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Decomposers (detritivores) are the 'recycling center' of your model Earth. They break down organic compounds into inorganic nutrients like Nitrogen and Phosphorus, which the plants then absorb through their roots to grow again.
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If you add too many animals (consumers) and not enough plants (producers), the oxygen levels will drop too low. If you add too much water, fungi might take over. Like Earth, the terrarium requires homeostasis, which means a stable internal balance.
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The Carbon Cycle on Earth
Check ut all the players involved in the Earth's Carbon Cycle:
How do you think this relates to a closed terrarium?
What are the "players" in our terrariums?
Let's see!
What are the "players" in our terrariums?
Let's see!
The Carbon Cycle Players
The carbon cycle is essentially a relay race of carbon atoms moving between gas and solid forms.
- The Producers (Plants/Moss): They are the "Carbon Catchers." Using sunlight, they pull CO2 from the air to build their bodies (glucose/cellulose).
- The Consumers (Springtails/Microbes): They are the "Carbon Releasers." When they eat decaying plant matter, they perform cellular respiration, which chemically breaks down sugars and exhales CO2 back into the jar’s atmosphere.
- The Decomposers (Fungi/Bacteria): These are the "Recyclers." They break down dead matter that neither the plants nor the bugs can use, ensuring carbon doesn't stay "locked" in dead leaves forever.
In our Earth's matter cycles, no new atoms are created or destroyed! They are just rearranged. The Carbon atom that was in a CO2 (Carbon Dioxide) molecule on Tuesday might be part of a leaf's sugar on Wednesday, and back in the air by Thursday after a springtail eats it!
The Water Cycle Players
The water cycle in a jar is a closed loop driven by temperature changes.
- The Energy Source (Sunlight): While not a physical "part" of the jar, it is the engine. It heats the liquid water, turning it into water vapor (evaporation).
- The Plants (Transpiration): Plants play a massive role here! They pull water from the soil and release it through tiny pores in their leaves (stomata). This is called transpiration.
- The Glass Walls (Condensation): The glass acts as the upper atmosphere. When the warm water vapor hits the cooler glass, it turns back into liquid droplets.
- The Substrate (Soil/Drainage): The clay beads and soil act as the "Earth's Crust." They store the water (collection) and allow it to be filtered and re-absorbed by roots, starting the cycle over again.
