Earth's Many Environments
An environment is a collection of all the animals and plants in
a specific area of land or water. Examples of environments are wetlands, deserts,
grasslands, forests, and oceans. Scientists also refer to environments as ecosystems.
Many people use the two terms interchangeably, for example, “desert
environment” or “desert ecosystem.” Each environment has
its own characteristics such as climate,
soil or water make-up, and plant and animal life. Sometimes people just talk
about “the environment.” They might say, “We need to help
protect the environment.” What they mean is everything on Earth — the
whole Earth environment.
Physical and Biological Environments
Earth is the only planet in our solar system - or anywhere else in the universe
we know of - that has environments that support animal and plant life. Earth’s
environments exist under a thin layer of protective gases called the atmosphere.
Environments are shaped by many factors, one of which is weather.
Scientists are interested in both physical
environments and biological environments. A physical environment is made up
of elements such as the atmosphere,
climate, land, and water. The biological environment includes animals, plants,
and bacteria. Both the physical and biological environments are connected to
each other and can never be separated.
Environments Keep Changing
Environments are always changing. Day by
day as weather, temperature, and daylight change, an environment also changes.
Seasons are an example of how an environment can change. Your environment may
have seasons very different from the environment kids somewhere else on Earth
Changes Can Be a Big Deal
Some events have a huge impact on the environment. Hurricanes like Isabelle
in 2003 dumped millions of liters of water on the southern coast of the United
States. Much of the water will refill underground water supplies that plants,
animals, and people will use for many years.
Environmental changes may be small or large. Water levels changing at the
beach may seem hardly noticeable to us, but they can be very important to a
crab. Changes after a hurricane or
volcano can be dramatic. They may cause the plants and animals that live in
the environment to change or disappear.
Changes Can Take a Long Time
Environmental changes may take only a few months or years. Some may occur
over hundreds or thousands of years. We humans only live about 60 to 80 years,
so we often only think of environmental change based on what happens in our
Types of Environments
Different types of environments exist all
over our planet. When you are in the middle of one it is often easy to see
what makes it special. Around the edges it becomes more difficult to recognize.
It starts to blend with the environment it borders. These edges are places
of great species diversity.
Scientists divide environments into smaller groups to better explore them
and explain them. For example, forests are one of the major types of environment.
But, there are different types of forests in different parts of the world.
For example, rainforests are one forest type. Even rainforests are divided
into tropical rainforests and temperate rainforests.
Urban environments may look different from other environments until you examine
them closely. Urban environments have animals, plants, and resources just as
other environments do. If you live in an urban environment, think about where
your town meets the next type of environment. What different kinds of plants
and animals begin to appear?
Tropical rainforests have the greatest number of animal and plant species
of any environment on Earth. Located on either side of the equator, tropical
rainforests are warm and wet. They get at least 200cm of rain each year. These
environments are very lush. The forests support so much life, because they
are always wet and receive the same amount of sunlight almost every day. Constant
conditions help many species of plants and animals develop and survive.
Deserts are defined by how much rain they get. Most deserts, like the Sonoran
in North America and Sahara in Africa, are hot. They receive less than 25cm
of rain each year. The South and North Poles are also deserts but very cold.
Despite extreme cold weather, polar environments still have plant and animal
diversity. Birds and mammals that live there are adapted to survive the polar
The southernmost polar region is called Antarctica, which means "no bears." The
northern polar region is the Arctic. The name “Arctic” comes from
the Greek word arctos, meaning “bear.” Polar bears are
the bears of the Arctic. Polar penguins live only in Antarctica. They are a
type of flightless bird.
Wetlands are environments where the land and the water meet and mix. Types
of wetlands are swamps, bogs, marshes, and fens. Many wetlands have local names.
In Canada, bogs are called muskegs. In the southeastern United States, swamps
are called bayous.
Each wetland type is classified by the plant species that live in it. The
world’s major wetland swamps are located in Africa, North America, South
America, and Asia. The largest wetlands in the world are the bogs of the western
Siberian lowlands in Russia. These bogs are three times the size of the United
Kingdom. Wetlands are becoming one of the most endangered environments. Many
of the animals and plants living there are also endangered.
Oceans are the large body of continuous salt water that cover over 70% of
Earth's surface. Earth has five oceans including the Atlantic, Pacific, Indian,
Arctic, and Southern oceans. It also has 13 seas. Both vertebrates and invertebrates
flourish in the ocean environment, including the smallest and largest animals
Grasslands are environments where grasses are the main type of vegetation.
The grass species are usually mixed with herbs and sometimes with shrubs. Less
than 10% of the land is covered with trees. Grasslands are found on every continent
In Africa (and elsewhere) grassland dotted with trees is called savanna. Grassland
wildlife species include horses, elephants, zebras, antelopes, buffalo and
bison, hawks, and snakes.
Environments and People
Many years ago, there were fewer people than
there are today. This meant their impact on the environment was smaller. As
human populations increased over time, so did their effect on the environments
Today, there are over 6.3 billion people on Earth. The quantity of natural
resources we consume is creating more and faster changes to the environment
of the whole Earth. Human activities can have huge and long-reaching impacts
that affect multiple environments.
For example, people cut trees in the tropical rainforests of Borneo to sell
the wood to furniture makers in Thailand. They, in turn, sell their tables
and chairs to people in Europe, North America, and elsewhere. In this way,
a human activity, say, buying furniture in North America, may be linked to
damage to the tropical rainforest home of orangutans - halfway around the world.
This happens because all species and environments are connected.
In upcoming years, people will need to keep
working together to solve environmental problems. Urgent problems include overfishing in
the oceans, cutting rainforests, draining water from rivers and wetlands, and
polluting of the air and water caused by cars and factories.
The solutions will come from conservation and the creation of new technologies
that need fewer resources.
Conservation is important to make certain that changes in the environment don’t
happen too quickly. Rapid change can cause animals, plants, places, or people
to become endangered or extinct.
Each of us plays a very important role in conservation each day through the
resources we use, reuse, and recycle.