Ecosystems have the potential to be sustainable over long periods of time.
Something is sustainable if it can continue indefinitely depending on nothing but itself. The concept has become increasingly well-known as it has become evident that current human uses of resources, mostly fossil fuels, are unsustainable. Our supplies of fossils are finite, aren't currently being renewed and consequently, cannot carry on indefinitely.
For an ecosystem to be sustainable, it requires three things:
Nutrients can always be recycled, therefore if this is possible in an ecosystem there should never be a lack of chemical elements. Similarly, the waste products of one species are usually used as a resource by another species. The best example to portray this is the decomposers role in an ecosystem, as they release ammonium ions that are then absorbed and used as an energy source by Nitrosomonas bacteria in the soil. While the ammonium is potentially toxic,the interaction between these two species does not allow it to accumulate in the ecosystem. Energy on the other hand cannot be recycled, therefore each ecosystem needs a constant supply of energy to survive.
Something is sustainable if it can continue indefinitely depending on nothing but itself. The concept has become increasingly well-known as it has become evident that current human uses of resources, mostly fossil fuels, are unsustainable. Our supplies of fossils are finite, aren't currently being renewed and consequently, cannot carry on indefinitely.
For an ecosystem to be sustainable, it requires three things:
- Nutrient availability (as was discussed in the Inorganic Nutrients & Nutrient Cycles page).
- Detoxification of waste products (carried out by decomposers).
- Energy availability (from the sun).
Nutrients can always be recycled, therefore if this is possible in an ecosystem there should never be a lack of chemical elements. Similarly, the waste products of one species are usually used as a resource by another species. The best example to portray this is the decomposers role in an ecosystem, as they release ammonium ions that are then absorbed and used as an energy source by Nitrosomonas bacteria in the soil. While the ammonium is potentially toxic,the interaction between these two species does not allow it to accumulate in the ecosystem. Energy on the other hand cannot be recycled, therefore each ecosystem needs a constant supply of energy to survive.
Building a Mesocosm
Mesocosms are small experimental areas to carry out ecological experiments, and in our biology class we set up sealed mesocosms to simulate a sustainable ecosystem. This is how we did it:
PLANNING FOR MESOCOSM
Alia Maiz & Samantha Chandra
Things we need:
As was mentioned before, if the experiment fails, moss should be the first to show signs this occurring as it will be the first to die, yet overall success will be measured by the conditions of the plants in general after several week.
Other comments:
We originally planned to plant seeds into our mesocosm and see if they would grow or not, but after putting everything together and adding a lot of other things (like moss and fungi), we realized that we didn’t have enough space in the jar for more organisms, and that if we were to plant the seeds they would probably not be able to grow because they would have to compete with so many other organisms for nutrients.
PLANNING FOR MESOCOSM
Alia Maiz & Samantha Chandra
Things we need:
- Jar
- Soil taken from the ground
- Sapling/seedling (young plant) from garden
- Rocks
- Charcoal
- Moss
- Fungi
- Put the rocks in the jar and make sure they are spread out evenly.
- Put small pieces of charcoal on top of the layer of rocks.
- Put the soil into the jar (to fill in about half of the jjar).
- Take out the seedling/young plant from the ground with a little bit of soil from the garden.
- Put the seedling into the jar and make sure it is planted firmly.
- Place moss and fungi on the surface of the soil.
- Water the soil to simulate rainfall.
- Seal jar.
- Water the plants every 3 days.
- Soil from the garden will contain bacteria and microorganisms (and possibly worms) to recycle the waste from plants (e.g dead cells in the root, fallen leaves, etc.). Along with the funghi we included (which are saprotrophs), they will act as the decomposers so that nutrients like nitrates, phosphorus, magnesium, and everything else they need in order to grow will be released back into the ecosystem to be used again.
- Rocks/stones underneath the soil prevents the soil from becoming too damp (allows water to trickle down into the stones) so that the roots of the plants won’t rot and grow mold, which is not healthy for the plant.
- Charcoal is used to provide a source of carbon, which is part of the nutrients needed for the ecosystem.
- The seedling and moss will be doing the job of producing oxygen during the day through photosynthesis and producing carbon dioxide through respiration (to be used again in photosynthesis). Moss is also a bio-indicator, meaning that because everything it needs is directly absorbed from the air or ground through its leaves, it reacts more quickly to changes in the environment than plants with roots. For us, this means it will be an indicator of the success of our experiment.
- Energy availability: artificial UV light provides light energy.
- Detoxification of waste: done by microorganisms in the soil.
- Nutrient availability: Carbon is provided by the charcoal, and nitrogen is provided in the air. Carbon cycle done by seedling, nitrogen cycle aided by nitrogen fixing microorganisms. Nutrients are recycled by the decomposers.
As was mentioned before, if the experiment fails, moss should be the first to show signs this occurring as it will be the first to die, yet overall success will be measured by the conditions of the plants in general after several week.
Other comments:
We originally planned to plant seeds into our mesocosm and see if they would grow or not, but after putting everything together and adding a lot of other things (like moss and fungi), we realized that we didn’t have enough space in the jar for more organisms, and that if we were to plant the seeds they would probably not be able to grow because they would have to compete with so many other organisms for nutrients.
The Importance of Sustainability
With the society we have built, at this point the future of our environment, and inherently our own future as well, is looking very bleak. Global warming is causing dramatic climate change that is affecting habitats all around the world, pollution is contaminating even more of our precious flora and fauna, our main source of resources (fossil fuels) is running out and at the moment we are no where near depending entirely on renewable energy, and on top of that, industrial agriculture has become the greatest source of food of our planet, and it is entirely unsustainable. Yet, while that all sounds quite depressing, there is always something we can do to stop ourselves from destroying our home. One of the newest upcoming solutions is the permaculture ideology. "Permaculture is a creative design process that is based on ethics and design principles. It guides us to mimic the patterns and relationships we can find in nature and can be applied to all aspects of human habitation, from agriculture to ecological building, from appropriate technology to education and even economics." (Permaculture Principles, 2015)
Find out more about this great movement by clicking on the link attached to the quote above and watch the video to the left! If you want to get involved find out if there is any non-profit organisation in your area that works with permaculture-if you are living in Bali, like the Permablitz Bali Facebook page by clicking here) or take a course through the Permaculture Institute by clicking here! Also, if you are looking for ways to make your lifestyle healthier and more eco-friendly, watch the Origins documentary on the right, as it gets into great scientific detail as to how we can stay healthy and preserve our planet. |
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