Bioindicators
Bioindicators are species of animals
Bryan Tan Kwang Shing 2O1 (4)
Introduction
The introduction of
contaminants into our natural
environment which causes
harm, disorder and instability
to the ecosystem is called
pollution. Pollution takes place
in many forms, such as water,
air, light, heat and sound. In
this pamphlet, bioindicators,
bioamplification,
bioaccumulation, bioremediation
and the importance of
minimising pollutions would be
introduced.
Water Pollution
or plants used to track an
ecosystem. These organisms show
the presence of the different
pollutants by responding with
different symptoms. They are able
to provide us with information on
The pollution might cause the
shortage of an important food
source for one species of animal.
As a result, these animal species
would not have enough food and
die. The other animals in the
food web would also be affected.
the changes in the ecosystem, be it
chemically, physiologically or
behaviourally. Contents of certain
elements or compounds, behaviour,
population structures, metabolicbiochemical and the cellular
A Caddisfly is usually used as an
structures tell of the bioindicators
indicator of water quality
us about those changes. Usually,
Bioaccumulation
mosses, tree bark and lichens are
Bioaccumulation occurs when
used as plant indicators (lichens are
Persistent Bioaccumulative Toxic
not plants as they are both fungi
substances, such as the harmful
and algae). For example, a high
DDT and methylmercury, enter
level of sulphur dioxide could be
an organism through breathing,
deduced from a sudden
ingestion or skin contact more
disappearance of lichens in an
quickly than it can leave the
ecosystem. These plant indicators
organism. As a result, that
also help to indicate toxicity levels
organism has a much higher
in our environment. A sudden
concentration of those
increase or decrease in an animal
substances than its surrounding
population might show damage
environment.
caused by pollution.
Bioremediation
Bryan Tan Kwang Shing 2O1 (4)
Bioremediation is the usage of
microorganism metabolism to
remove pollutants in our
Bioamplification
environment. Bioremediation is
Bioamplification, is also known as
usually categorised as in situ
biomagnifications. It occurs when
bioremediation or ex situ
a PBT, accumulated in one part
of the ecosystem, increases in
concentration for every
consecutive trophic level. For
example, pollution causes a water
body to be polluted with
pesticides. Fishes are
contaminated with pesticides.
These fishes are in turn eaten by
other animals or humans.
These contaminants are
accumulated in the tissues and
they get more and more
concentrated with every
increase of trophic level as
predators tend to have a longer
lifespan than their prey and
each trophic level contains less
biomass with every consecutive
trophic level.
Bioamplification in our
environment
Impacts
bioremediation. The former
refers to the treating of the
contaminated materials at the
site while the latter refers to
Bioaccumulation and
the treating of contaminated
bioamplification are closely
materials away from the site.
related and they cause negative
To date, bioremediation is
impacts to our ecosystem. For
unable to easily treat all
example, if DDT is
contaminants, such as lead and
bioaccumulated and bioamplified,
cadmium as they are not
it will cause shell-thinning in
readily absorbed by organisms.
contaminated birds’ eggs. Also,
The accumulation of metals such
high level of mercury would
as mercury into food webs
impair some animal’s
might also make matters worse.
reproductive success. For animals
Organisms are genetically
in the higher trophic levels,
modified. A good example would
biomagnified contaminants would
be the Deinococcus radiodurans.
lead to the decrease of bird rates,
It has been modified to consume
increase of death rates and thus
ionic mercury from highly
cause a declining population.
radioactive nuclear waste.
Water pollution causes more than
Bryan Tan Kwang Shing 2O1 (4)
14,000 deaths a day in
developing countries. Nearly 700
million people living in India have
The usage of bioremediation is not
only cost-effective but it is also
efficient which can be used in
areas not easily accessible.
no access to proper toilets and
close to a thousand die of
diarrhoeal every day.
Water pollution, in forms of oil
spill, causes not only skin
irritation and rashes; it causes
deaths of many marine animals.
Water pollution in the form of
heavy metals might pass through
the various trophic levels,
Importance of Minimising
Pollution
increasing in concentration in the
process.
which damages plants.
due to the rising level of
atmospheric carbon dioxide would
cause a slight but critical increase
in acidity of ocean waters. This
might cause deaths of marine lives
would might disrupt the marine
ecosystem. In order to minimise
the number of people and animals
dying due to pollution, we have to,
obviously, minimise pollution.
‘R’s – Reduce, Reuse and Recycle.
cardiovascular diseases, chest pain
production of tropospheric ozone
Recent studies have shown that
play our part by practicing the 3
respiratory diseases,
receive. This will lead to the
condition of global warming.
released into the air. We can also
smog and haze might cause
amount of sunlight the plants can
heat than usual, worsening the
to minimise the pollutants
environment. Air pollution, like
photosynthesis due to the reduced
atmosphere would traps more
Collection Systems and Scrubbers
human health and our
and haze also reduce the rate of
industrial sites accumulate in our
Industrial sites also use Dust
Pollution in all forms harms
and throat inflammation. Smog
Greenhouse gases released by
The most direct consequence as
shown by the examples above is
the harm of human health and
our environment. However,
pollution indirectly contributes to
global warming.
Special Thanks To
1 http://tinyurl.com/dgm9jg
2. http://tinyurl.com/3dndysp
3. http://tinyurl.com/3bxt8u9
4. http://tinyurl.com/3hhoq6t