"The deeper we look into nature the more we recognize that it is full of life, and the more profoundly we know that all life is a secret, and we are all united to all this life."
Albert Schweitzer
ACTIVITIES
What is ecology?
What we are concerned about when we are dealing
with ecology is how living beings are related to each other and the conditions
they are living in. A living being affects and is affected by other beings
of its own species and of other species. What all beings in general require
for survival (energy, shelter, etc.) and also for the continuing existence
of their species are the main factors determining the nature of these
relationships. Besides that the non-living environment has a great influence
on the lives of all other living and non-living things forming the ecosystems.
Physical Environment
Soil, air and water mainly make up this non-living environment. In
addition to these, the sunlight effects the living conditions to a great
extent. The production of food inside plant bodies, which initiates the
chain of life, would not take place in the absence of sunlight. The existence
of plants and all other living beings in return would cease if it were
not for the sun. Temperature also depends mainly on sunlight. In return,
humidity, which is a measure of the amount of water vapour present in
air, is dependent on temperature. Temperature and humidity are two important
factors to influence the living beings greatly.
Soil Component
As for the soil, it's indeed more than what we imagine. It's not only
the covering of the earth-surface, the part that we stand on, live on,
and where the plants are attached to. It's also the home for many living
beings, such as microorganisms, worms, mice, moles, rabbits, snakes, bacteria,
fungi, alga, shrubs,etc. What it contains depends on dwelling things in
or on it as well as the temperature water and the humidity in the area.
It contains many decayed animal and plant material. The organic content
of soil differs according to species living on it since some special species
prefer different areas. Similarly the inorganic part varies again in different
areas. Different rocks for example, when they are smashed into little
pieces under the influence of water, wind, and temperature differences,
form different types of soil.
Water component
Although soil is what comes first when considering a home for the living
-since we are land-dwelling beings - another great host is water. More
than a half (and slightly less than three quarters) of the world is covered
with water: in oceans, in lakes, rivers, glaciers, as subsurface water.
It also exists in all living beings' bodies and in air as mentioned previously.
However, although water seem to exist abundantly on Earth, the water the
living things require for their survival, the fresh water, is only about
1% of all of the existing water on the Earth.
Journey of water
Water indeed travels all the time, sometimes flowing on the ground, sometimes
from the roots to the leaves of a tree, sometimes through an animal's
body or sometimes high up in the sky in the clouds. Meanwhile, entering
and leaving those stations it passes by, water can exist in solid, liquid,
gaseous states and it continuously changes from one state to another.
With the heat form the sun, together with the wind force water evaporates,
thus begins to move upwards (similar to the water vapor getting out of
animals' bodies, plants' leaves) where it comes together to form the clouds.
Later on, when the vapor particles pass through a colder area in the sky,
they turn back to the ground as rain or if further colder area, as in
the form of snow. Some fall on the oceans, seas, rivers, again some fall
on the soil from where plants get them with the help of their roots. They
use some and give back some of the particles out to the atmosphere through
their leaves similar to the way we human beings breathe away some vapour
during our respiration through our mouth.
Fitted to the nature
All living beings need to be well-adopted to and be in harmony with the
conditions where they are living because they need to maintain somewhat
stable conditions in their bodies. The cactus, for example, is adapted
to the arid desert conditions. It stores water in its body and conserves
moisture by reflecting some of the sun-rays with the help of its fleshy
tissues in its stem and has modified leaves as in the form of spines which
helps it to avoid heat. The arctic fox, on the other hand, lives in another
extreme of climatic conditions, and reduces heat loss by the help of its
white fur, and several internal features which help it maintain its body
in a stable state especially in terms of the body temperature. Beside
these examples from extreme climatic conditions, all living beings have
special mechanisms fitting a specific area, which provide the ideal living
conditions for them. We give the name "ecosystem" to those specific
areas together with the species living there and their surroundings. This
can also be considered vice versa, that is, the living beings maintain
suitable features that fit to that specific area. Actually this is a two-way
process, which continues for long years and which selects the most suitable
individuals for various environmental conditions thus provides a harmony
between living-beings and their surroundings. That's why this process
is called "natural selection".
Cycles & Energy
Just as energy is passed on from one being to another through what we
call the food chain, all the materials, which make up living bodies e.
g. carbon and nitrogen, are recycled over and over.
Photosynthesis and The Food Web
The plants ,instead of 'feeding' on other living-beings produce their
own food. With the help of sunlight plants turn water (which they take
up through their roots) and carbondioxide (which is one of the components
of the air , in a very small amount though) into a substance we call glucose,
which is the basis of the substances living beings feed with. Meanwhile
plants give out oxygen which is vital for all other living beings and
all this process is called "photosynthesis". Therefore, plants
are able to make use of sunligth to make food and when animals eat plants
they obtain necessary nutrients and energy and in turn they are eaten
by other sorts of animals. For example, a worm takes up the necessary
energy for its living by feeding on a tree's leaves and then so does the
bird by eating the worm. This web of feeding (food web) is based on the
need of all living beings for energy and at the same time provides a great
diversity of species on earth by controlling the populations of other
species.
Living Together
The living-beings not only live in relation & harmony with the non-living
environment but also with other living-beings. A tree, for example, while
being an obstacle for a bush growing in the neighborhood (because its
leaves shield the sunlight which is also necessary for the bush) it might
be at the same time a home for a bird and a beetle, as well as being a
means of feeding for a squirrel and a worm maybe. On the other hand, it's
just a ring in the chain of life, existing for only a small period of
time in the form of what we human-beings call a "tree". When
it dies , it will be the beginning for other forms of life.