Ecosystems in a Jar
Make a sustainable ecosystem for your organism(s) in a sealed environment - with no access to oxygen or external factors such as rain, air and pollution.
Ecosystems can be difficult to analyze because they are so big and complex. Scientists use an experimental tool called the mesocosm to help analyze natural systems. The mesocosm consists of the resources and materials found in the ecosystem in question. They are placed in a sealed, clear container to allow access to sunlight while controlling all the other conditions within the system. Ecosystems are considered sustainable or not if the organism is able to survive within the mesocosm.
Much like how an eclipse provides scientists a chance to study variables affecting weather on a grand scale, a mesocosm offers a controlled environment that enables scientists to meticulously investigate and understand how specific variables influence ecosystems and climate on a more localized and manageable level. In both instances, these controlled settings provide invaluable opportunities for scientific inquiry, allowing researchers to explore the intricate interactions between environmental factors and their impact on the broader climate system.
This activity is a shorter version of the workshop Exploring Ecosystems developed by the Let’s Talk Science National Office.
What You Need
- Glass jar (or clear-plastic container/bottle without shoulder + neck)
- Plastic wrap and rubber band
- Water
- Soil or potting mix
- Small stones or pebbles
- Organisms of choice
- Plant or succulent (from seed or initially grown) *basil plants work well
- Insect or organism (e.g Worms)
- Moss
Guide:
Safety Notes
Refer to the Learning Through Nature Quick Reference Guide for facilitating an outdoors outreach visit.
What To Do
- Go outside and collect all the materials from a nearby park or forest.
- Add stones and pebbles to the bottom of the jar in a small layer for drainage.
- Add a layer of moss (if available).
- Add a thick layer of potting mix or soil, about 1/4 of the jar.
- Add your plants or seeds + any other organisms you collected.
- Decorate with more stones, shells or other ornamental finishings. Make sure to leave room in the jar for the plant to create an atmosphere and grow.
- Add some water. The amount of water required for your system to be self-sustaining is specific to your mesocosm. Try adding enough to soak the bottom layer of pebbles. If the soil seems dry you can add more water.
- Seal the container with plastic wrap and a rubber band.
- Leave mesocosm under an open, sunny area.
- Observe your mesocosm for a few weeks – what happens to the organism? Is your mesocosm sustainable?
- Reminder: Do not open the lid.
Discovery
Ecosystems consists of all the living organisms (plants, animals, microorganisms) and non-living things (water, rocks, temperature, etc.) in an area. Everything in an ecosystem is connected either directly or indirectly through processes. Therefore, one change in an ecosystem can have wide ranging impacts on all the other components in the ecosystem.
If a mesocosm is sustainable for life, the plant should grow while remaining sealed. This is because plants are able to create their own food and oxygen through the process of photosynthesis – as long as the mesocosm has access to enough sunlight and nutrients in the soil. The presence of bacteria in the soil also allows for nutrient recycling. Signs of growth include the plant becoming larger/taller, the appearance of roots in the soil and condensation on the lid/cover. Condensation may occur and cause pressure and push up on the plastic wrap.
Mesocosms are an important tool that connect field studies to laboratory research – they allow scientists to study the effects of different factors on an ecosystem within a simulated environment.
Mesocosms can be useful in the study of the effects of climate change on different ecosystems. Climate change refers to long-term changes in the Earth’s temperature, precipitation and weather patterns due to human activity that releases greenhouse gases into the atmosphere. These gases form an invisible layer that traps the sun’s rays and cause the Earth to heat up faster than it should (global warming). Mesocosms allow scientists to recreate a small portion of an ecosystem and alter different factors (such as composition, temperature, nutrient availability, etc.) associated with climate change. How the mesocosm and organism(s) responds to those changes give scientists a better understanding of the potential consequences of climate change and allow them to make more accurate projections.
- If your mesocosm is determined to be sustainable, conduct another experiment by changing a factor, such as the amount of light or water available, altering the temperature, or by adding something to the soil (i.e. baking soda or vinegar for pH) to see how that affects the organism.
- Research different climate trends that may affect your community and adapt your mesocosm to simulate those changes.
- How does your organism respond to the changes? What does this mean about the future?
- What are some actions we can take to prevent these changes from occurring?
- Resources on the Environment (STEM in Context) – a resource page including articles and careers profiles related to the environment.
What's Happening?
Ecosystems consists of all the living organisms (plants, animals, microorganisms) and non-living things (water, rocks, temperature, etc.) in an area. Everything in an ecosystem is connected either directly or indirectly through processes. Therefore, one change in an ecosystem can have wide ranging impacts on all the other components in the ecosystem.
If a mesocosm is sustainable for life, the plant should grow while remaining sealed. This is because plants are able to create their own food and oxygen through the process of photosynthesis – as long as the mesocosm has access to enough sunlight and nutrients in the soil. The presence of bacteria in the soil also allows for nutrient recycling. Signs of growth include the plant becoming larger/taller, the appearance of roots in the soil and condensation on the lid/cover. Condensation may occur and cause pressure and push up on the plastic wrap.
Why Does it Matter?
Mesocosms are an important tool that connect field studies to laboratory research – they allow scientists to study the effects of different factors on an ecosystem within a simulated environment.
Mesocosms can be useful in the study of the effects of climate change on different ecosystems. Climate change refers to long-term changes in the Earth’s temperature, precipitation and weather patterns due to human activity that releases greenhouse gases into the atmosphere. These gases form an invisible layer that traps the sun’s rays and cause the Earth to heat up faster than it should (global warming). Mesocosms allow scientists to recreate a small portion of an ecosystem and alter different factors (such as composition, temperature, nutrient availability, etc.) associated with climate change. How the mesocosm and organism(s) responds to those changes give scientists a better understanding of the potential consequences of climate change and allow them to make more accurate projections.
Investigate Further
- If your mesocosm is determined to be sustainable, conduct another experiment by changing a factor, such as the amount of light or water available, altering the temperature, or by adding something to the soil (i.e. baking soda or vinegar for pH) to see how that affects the organism.
- Research different climate trends that may affect your community and adapt your mesocosm to simulate those changes.
- How does your organism respond to the changes? What does this mean about the future?
- What are some actions we can take to prevent these changes from occurring?
- Resources on the Environment (STEM in Context) – a resource page including articles and careers profiles related to the environment.