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The Biodiversity Dilemma: What is Biodiversity? |
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The word biodiversity
is short for biological diversity, it describes the
number of different kinds of plants and animals in a specific area.
Levels of
Biodiversity
This diversity can exist at three
different levels. All are very important and related to each other:
Genetic level: This includes the variety of genetic
information within a species or population. The more diverse its genetic code,
the more likely a species will survive changes in the environment. For example,
we have different types of apples. Some kinds are more resistant to
disease than others, while others may tolerate warmer climates.
Two examples of how important
genetic diversity is are as follows: The loss of Potato blight wiped out
the potato crop in
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Species
level: This level includes a
variety of different species within an ecosystem habitat that enables the
system to remain stable even with changes or disturbances. For example,
the salt marsh is full of a variety of different species including fish,
crabs, herons, gulls, etc. that help enrich the system. |
Most efforts to restore endangered
species populations are targeted at this level. The
Ecosystem level: This level is the variety of different
kinds of ecosystems within a region that
enable the regions to cope with changes or disturbances. For example, migrating
birds need two different kinds of ecosystems in two different parts of the
world as well as in healthy ecosystem rest stops along their route.
As we lose many different types of
ecosystems to development and consumption of natural resources, this level of
global diversity decreases. For example, filling in mangrove swamps to
build high-rise hotels on the coast or cutting down rain forests for grazing
land and the sale of prized natural resources such as mahogany and rubber is
dramatically decreasing the resiliency of
ecosystem diversity.
Ecosystem,
Species, and Genetic Resiliency
All three levels of diversity are
essential to maintain life on earth as we know it today. Each level must
be protected because they all depend on one another and must be resilient in
order to survive. It is the variety of genes, species, or ecosystems that
makes all three levels resilient.
The Importance
of Biodiversity
Here is an analogy to help you
understand what biodiversity does:
Let's pretend I'm giving you a
free ticket for a flight to
That's a lot like our ecosystems
and species diversity. We know plants and animals help our ecosystems provide
ecological services - like the photosynthetic plants that give you food energy,
and the decomposers that enrich your soil so trees are able to grow in order to
provide shade you.
Suppose we asked these
questions: "How many species do we have on this eco-ship?"
"How many do we need?" "Are some more important than
others?" "What is the minimum number we need to function?"
We don't know the answers. Now think about it, wouldn't you like to keep
as many of these rivets as possible?
How
Biodiversity Benefits Humans
So, when we lose biodiversity, we
lose access to many different plants and animals that we might need. Here are
some specific ways that biodiversity helps us:
Scientists use the genetic diversity
in our food crops so we can continue to grow plants that are resistant to pests
and disease. Many of our prescription drugs were first made from plants and
animals. If we continue to lose species, especially those not well researched
such as those in tropical forests, will lose out on potentially valuable
medicinal cures.
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Ecosystems also
help clean the air we breathe and the water we drink. |
Biodiversity stabilizes the
ecosystem. It keeps our options open for the future. There may be
resources out there that we don't yet understand their potentials, and we don't
want to destroy them before we even know about them. Biodiversity also
increases the beauty of the planet. What would
Saving a Whole
Ecosystem or Just One Animal in it?
So should we try to save whole
ecosystems or just one animal at a time?
Trying to preserve either a single
animal or even the ecosystem are both good ideas if in the long run they work
to save the area. When you try to save an individual animal, especially a keystone species, you must provide it with a
place to live and food to eat. What better place than its own habitat. Also, in the process of saving an
ecosystem, you save all of the other plants and animals in that ecosystem by
default. Sometimes it is easier to get people excited about saving an important
animal like a parrot or a panda rather than an ecosystem. So we use some animals
as ambassadors to get attention and operate in the limelight so we can protect
the lesser known plants and animals in the ecosystem.
What is a
Keystone Species?
A keystone species is one on which
many other species in the ecosystem depend. For example, in a longleaf pine sandhill, if you were to take out the gopher
tortoise, 
a
keystone species, then the ecosystem would change dramatically. For example,
the gopher tortoise digs burrows to live in and shares these homes with
hundreds of other animals. Without a protective place to live, all of those
other animals might die.
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EXTINCTION
It is true that extinction is a natural process, but never
before has it occurred at such a fast rate. And, depending on your view, it
is not happening because of natural reasons now. Due to human actions and
changes in our ecosystems, we have seen the extinction of thousands of
species in just the last two hundred years; it is natural for only about one
species to go extinct every hundred years. |
Causes of Loss
of Biodiversity
The easiest way to remember the five
main causes of biodiversity loss is to think of the acronym HIPPO. It stands
for:
Habitat loss
Some plants and animals require specific
habitats and cannot live without them. Because of increasing development
and other changes to the ecosystem, plants and animals are losing their needed
habitats.
Invasive species
When an invasive
species is introduced, into an ecosystem, it can change the entire makeup
of that ecosystem. Over time, it may push out many of the native plants and
animals. For example, melaleuca has replaced
indigenous species in
Population Growth
The growth of the human population is
increasing at an exponential rate, there are more and more people depleting
resources and taking away natural habitats to provide for homes, farms, and
roads.
Pollution
Humans continually contaminate the
air, water, and soil with their everyday lifestyles. This makes it a
bigger challenge for plants and animals to survive.
Over
consumption of natural resources.
Many scientists believe there are
enough resources on the planet if humans only use what they need. However, when
we have three TVs in one home, or enough clothes for a
month, we are wasting valuable resources. The energy,
and other raw materials used to make these products come from the environment.
The use of these resources often brings disruption or pollution to the plants
and animals. (The U.S, makes up 5% of the world
population, yet we consume more than 50% of the earth's natural resources.)
Ways to
Preserve Biodiversity
Here are just a few examples of ways
people are already helping preserve biodiversity:
* Landscaping
urban areas for wildlife;
* Restoring degraded coastal habitats
by planting mangroves or sea grass;
* Restoring longleaf pine forests by
supporting prescribed fire;
* Adding species to the Endangered Species List protects animals,
plants, and habitat;
* Developing environmentally friendly
manufacturing practices; and
* Keeping gene banks to preserve
genetic information for use later.
Here are some ways you and your
friends and family can get involved:
* Use native plants in the landscape
to provide food for native insects, birds, and other wildlife;
* Conserve natural resources;
* Support zoos and botanical gardens
that keep seed banks and live specimens of animals that are extinct in the
wild; and
* Recycle, reuse, and of course,
reduce consumption!
Bibliography
Keystone
species at Biodiversity
Loss: Cascade Effect.
Extinction rates at Species:
Unprecedented Extinction Rates and It's Increasing.
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