Lesson 4 Toward Sustainability
Looking to Nature for Help
Our environment is in trouble.
With the planet becoming warmer, sea levels are rising and natural disasters such as forest fires and floods are increasing.
More and more waste is also being produced.
Plastic, in particular, is causing problems with soil and water pollution.
It is clear that humans are a major contributor to the destruction of nature.
Will we be able to protect the environment from mountains of plastic?
Can we stop climate change from reaching dangerous levels?
Achieving these goals seems difficult.
Nature, however, may have provided us with solutions to these problems.
Here are three areas where changes are already happening.
Dealing with Plastic Waste
About fifty percent of plastic is produced for single-use products.
That means the items are used just once and then discarded.
Do you ever stop to think about where these plastic items go after you throw them away?
Recycling can help reduce the amount of plastic in our landfills.
However, less than ten percent of the world’s plastic waste has been recycled so far.
Often, plastic waste is moved to places where it is just dumped or burned.
Furthermore, between 8 and 14 million metric tons of plastic end up in the ocean every year.
This puts many marine species in danger.
With this in mind, scientists are turning to mealworms.
Mealworms are the larvae of a certain species of beetle.
Special bacteria live inside them.
These bacteria can break down plastic.
This means that mealworms can actually feed on plastic.
Scientists are now looking for ways to cultivate the bacteria outside of mealworms.
They also want to speed up the process by which the bacteria break down plastic.
This may help us keep our landfills plastic-free.
Purifying Polluted Soil
Mining and other industries are causing soil pollution across the globe.
Although polluted soil can be dug up and transported to a landfill, this process is expensive.
Moreover, it only moves the problem to another area and does not really solve it.
Fortunately, there is an eco-friendly and cost-effective way to restore polluted soil—planting willow trees.
These amazing trees have extensive and well-developed root systems.
As a result, they naturally extract a wide range of harmful materials from the soil.
They can also grow quickly, even in soil with a high acidity level or a lot of heavy metals in it.
Research on the effectiveness of using willow trees for this purpose is in development.
Scientists have found that some species of willow trees are able to absorb harmful materials better than others.
Therefore, this promising area should be further explored to find out which trees are the most effective.
In time, we may be able to clean up our land with willow trees.
Producing Algae Biofuel
Statistics show that about thirty to forty percent of people in the world drink coffee each day.
The coffee-making process, however, generates used coffee grounds, which are normally sent to landfills.
There, they can create a harmful greenhouse gas.
Unfortunately, there’s no way to stop everyone in the world from drinking coffee.
However, we can reduce greenhouse gas emissions by turning used coffee grounds into biofuel.
Biofuel is a natural fuel that is made from plant or animal sources.
Researchers have found that they can grow algae on old coffee grounds without adding any other nutrients.
If these algae are exposed to twenty hours of light and four hours of darkness each day, they eventually produce high-quality biofuel.
The biofuel is renewable and sustainable, and it creates only a small amount of emissions.
These are just a few solutions we can find in nature.
There could be many more possible solutions to the problems we currently face.
It seems that Mother Nature has given us one more chance.
In return, we need to look for more ways to keep the environment healthy and clean.
If we do, the future of our planet may be bright after all.
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