Bio-indicators are organisms used to assess environmental quality and ecological health through their responses to environmental changes, pollution, and ecosystem disturbances. Effective bio-indicators are abundant, well-studied, and sensitive to contamination, with examples including lichens and microorganisms, which can reveal changes in air and water quality. They play a crucial role in monitoring ecosystems and can provide quick assessments of contamination levels.

1. BIO- INDICATORS
AND
THEIR
APPLICATIONS

2. BIO-INDICATORS
Bio-indicators are biological indicators of environmental
quality, characterizing environmental conditions.
Bio-indication is a research activity allowing us to obtain a
picture of the ecological situation on the basis of its important
element (e.g. species, ecological form, population,
association or community).
Bio-monitoring can be defined as a process in which the
“analytical instruments” used, i.e. plant and animals or their
fragments, provide continuous, real time analytical
information.

3. PROPERTIES OF BIOINDICATORS
 Good Indicator Ability:
--Provide measurable response (sensitive to the disturbance or stress but does not
experience mortality or accumulate pollutant directly from their environment)
--Response reflects the whole population/Community/ecosystem response
--Respond in proportion to the degree of contamination or degradation
 Abundant and Common:
--Common including distribution within area of question
--Relatively stable despite moderate climatic and environmental variability
 Well Studied:
--Ecology and life history well understood
--Taxonomically well documented and stable
--Easy and cheap to survey
 Economically/Commercially important
--Species already being harvested for other purposes
--Public interest in or awareness of the species.

4. Bio-indicators selection criteria
 Abundance or wide distribution
 Simple procedure of identification and sampling
 High tolerance for the pollutants analyzed,
 Population stability
 High accumulating capacity

5. • The organisms and organism associations are monitored for changes that
may indicate a problem within their ecosystem.
• Bio-indicators are organisms, such as lichens, birds and bacteria, that
are used to monitor the health of the environment.
• The changes can be chemical, physiological or behavioral. Specific
physiological and behavioral changes in bio indicators are used to detect
changes in environmental health.
• Bio indicators are relevant for Ecological health.
Bio indicators are used to: detect
changes in the natural environment,
monitor for the presence of pollution
and its effect on the ecosystem in
which the organism lives, monitor the
progress of environmental cleanup and
test substances, like drinking water for
the presence of contaminants.

6. Types of bio-indicators and uses
MICROBIAL INDICATORS –
 Microorganisms can be used as indicators of aquatic or terrestrial ecosystem health.
 Found in a large quantities, microorganisms are easier to sample than other
organisms.
 Some microorganisms will produce new proteins, called stress proteins , when
exposed to contaminants like cadmium and benzene.
 For example , microbial indicators can be used for testing water: Bioluminescent
bacteria are being used to test water for environmental toxins .
 If there are toxins present in the water, the cellular metabolism of the bacteria is
inhibited or disrupted.
 This affects the amount of light emitted by the bacteria. Unlike traditional tests, this
one is very quick-taking from five to thirty minutes to complete. However, it only
indicates the presence of a toxin causing the change in the organism.
Phytoplankton Zooplankton ,Herring gull’s eggs ,and diatoms and various other
microorganisms.
Examples:

7. • Plant organisms play an important role in their natural habitats - they supply
oxygen, control organic substance circulation and biological balance of the soil
and bottom deposits, provide food and shelter to other organism.
• Phytoindicators are more and more frequently used for ecosystem quality
assessment due to their sensitivity to chemical changes in environmental
composition and the fact they accumulate pollutants.
• The use of plants as bio-indicators has many advantages, including low costs,
the possibility of long-term sampling and high availability.
• Lower plant organisms (grasses, mosses, lichens, fungi and algae) are used
most often in analyses of atmospheric depositions, soil quality and water
purity.
PLANTS AS BIO-INDICATOR

8. • 2) PLANT INDICATORS - The presence or absence of certain plant or
other vegetative life in an ecosystem can provide important clues about the
health of the environment.
• Lichens , often found on rocks and tree trunks, are organisms consisting of
both fungi and algae.
• They respond to environmental changes in forests , including changes in
forest structures , air quality, and climate.
• The disappearance of lichens in a forest may indicate environmental
stresses, such as a high levels of sulfur dioxide, sulfur-based pollutants , and
nitrogen.
LICHENS-a simple slow-growing
plant which typically forms a low
crust-like, leaf-like, or branching
growth on rocks, walls, and trees.

9. • Mosses and lichens are applied as indicators of
environmental pollution due to their capacity to accumulate
and store heavy metals and other toxins.
• Typical examples of a biological indicator of air pollution are
lichens.
• Their major advantage is response repeatability in various
habitats.
• Regardless of the investigation site and differences in the
species composition, destruction zones are easy to
distinguish.
• Due to their specific anatomic, morphological and
physiological characters, lichens are among the organisms
that die first as a result of excessive air pollution

10. Bio-indicators of Aquatic Ecosystems
• The organisms used as bio-indicators must be
characterized by much higher sensitivity than the best
chemical indicators.
• Aquatic organisms accumulating pollutants allow us to
detect them even when their water concentrations are too
low to be detected.
• An example may be determination of radioisotope activity
in plankton, which is several times higher than in water.

11. • The water purity state should be determined using
organisms sensitive to pollution, characterized by a narrow
range of tolerance.
• The following tests and bio-indicators can be applied to
analysis of water and sewage toxicity test based on
Chlorella vulgaris – a unicellular green alga, widespread in
fresh waters.
• Diluted sewage solutions are introduced into laboratory
algal cultures, then absorbance is measured with a
spectrophotometer in the visible range.

12. REFERENCES
Some Considerations About Bio-indicators in Environmental Monitoring
R. Gadzała-Kopciuch1*, B. Berecka2, J. Bartoszewicz2, B. Buszewski1
Bio-indicators in Human Environment