biology project on algae
DESCRIPTION
project work for CBSE class XII - biologyTRANSCRIPT
INVESTIGATORY PROJECT IN BIOLOGY
A STUDY ON HARMFUL EFFECTS OF
ALGAE ON WATER BODIES
Submitted byAparna P. Nampoothiri
SHANTHINIKETAN SCHOOL(Senior Secondary)
Kunnumpuram, Vilappil, Thiruvananthapuram – 73
CERTIFICATE
This is to certify that project in Chemistry entitled A STUDY ON
HARMFUL EFFECTS OF ALGAE ON WATER BODIES is a
bonafide record of work done by Kum. Aparna P. Nampoothiri
Reg No. ……..……………for the requirement of CLASS XII practical
examination of AISSCE during the academic year 2012 – 2013.
Teacher in charge External Examiner
Head of the institution
TABLE OF CONTENTS
Topic Page no:
1 Acknowledgement 4
2 Introduction 5
3 What are algae ? 5
4 Types of algae 6
5 Habitat 6
6 Importance of algae 6
7 Harmful effects of algae
8 7
9 Objective 8
10 Theory 8
11 Requirements 9
12 Procedure 11
13 Observations and calculations 12
14 Result 14
15 Conclusions 14
16 Bibliography 15
ACKNOWLEDGEMENT
I acknowledge with gratitude the immense help and knowledge
provided by Sri. Sam …......, our teacher of Botony and my grateful
thanks are to him for his able teaching and guidance. I also thank the
school authorities, my parents, my aunts and uncles, my brother and my
friends for their constant support and co-operation.
I also thank Smt. Sajitha Rajan, Lecturer, All Saints College,
Trivandrum for the able guidance provided and the College Authorities
for the immense help extended in using the laboratory facilities without
which this project would not have been complete in this full shape.
I also thank the Guruvayoor Temple authorities and other people
who have extended immense help to me in completing this project
successfully.
I also thank the almighty for all the blessings.
INTRODUCTION
I would like to draw the attention of all to the following news
clipping:
“A striking evidence of ignorance by various Governments and
its departments for keeping the heritage zones in
Thiruvananthapuram city clean, Sreevaraham and
Mithranandapuram ponds are few among them. But finally
there are some good news for heritage lovers of
Thiruvananthapuram. Thiruvananthapuram Corporation has
initiated a project to clean both ponds on an emergency basis.
A total amount of Rs.14 lakh is alloted for the 1st phase of the
project. The 1st phase includes cleaning the pond and
construction of sidewalls and beautification of its surroundings.
The Mayor of Thiruvananthapuram Corporation K. Chandrika
has inaugurated the project”.
My mother's sister lives very near to the Mithranandapuram
temple. Sreevaraham is also not far. Seeing the news clipping I decided
to visit the said ponds for ascertaining the facts. It was the first time that
I realized, algae can cause such a heavy damage to the water bodies. It
was learnt that algae have harmful effects also.
Hence I decided to have a study on presence of Algae on water
bodies such as ponds and their Harmful Effects thereon.
What are algae ?
Algae are a group of chlorophyll bearing, photosynthetic,
autotrophic, thalloid plants. Their body is not differentiated into true
roots, stems and leaves. They lack vascular tissue and epidermis with
stomata. The study of algae is termed Phycology. The term “algae” was
coined by Carolus Linnaeus. The form and size of algae are highly
variable. The size ranges from microscopic unicellular to colonial,
filamentous and to massive plant bodies. They fall into a heterogeneous
group of cryptogamic plants comprising thirteen large phyla.
Algal diversity
They fall into a heterogeneous group of cryptogamic plants
comprising thirteen large phyla.
As on date 40,000 algal species have been described. Another
3,60,000 species are believed to exist on the earth. A total of 834 species
of algae having reported from Kerala.
The blue-green algae are a large and morphologically diverse group of phototrophic prokaryotes
The green algae are cosmopolitan and occur in marine brackish, fresh waters and soil environments.
The brown algae are global in distribution and essentially marine.
The red algae forms the largest group and predominantly marine.
The Charophyta are predominantly freshwater
Types of algae
Algae are mainly divided into three classes: Chlorophyceae (green
algae), Phaeophyceae(brown algae) and Rhodophyceae(red algae).
Habitat
Algae are mainly aquatic. Algae thrive both in marine as well as
fresh water. They can also be seen in terrestrial habitats like moist soils,
wet rocks, tree trunks and moist walls etc. Aquatic algae are found in
water either completely submerged or free floating on the surface. In
fresh water bodies such as rivers, ponds, lakes etc they are seen either
floating in masses or attached to submerged bodies such are stones.
Some fresh water algae are Spirogyra, Ulothrix, Oedogonium, Zygnema,
Cladophora, Clamydomonas, Volvax etc.
In marine conditions the mostly seen are brow and red algae.
However some green and blue green algae also occur in marine
conditions. Examples of marine algae are Sargassum, Padina, Ulva,
Polysiphonia etc.
Terrestrial genera are found on or beneath the moist soil. Some
occur on the surface also. Eg. Vaucheria, Botrydium etc.
Terrestrial forms can be further classified as
- cryophytes (those that grow in ice). But these algae show specific
color effect under such conditions. Eg. Yellow Green color of
Chlamydomonas yellow-stonensis, red color of Chlamydomonas
Nivalis etc.
- aerophytes (those that are adapted for aerial mode of life) found in
tree barks, moist walls, flower pots, rocks, fencing wires etc. They
take water and carbon dioxide directly from atmosphere.
- thermophytes (those that are found in hot springs at quite high
temperature). These forms tolerate temperatures up to 850C. Eg.
Oscillatoria Brevis, Synechococcus Elongates etc.
Importance of algae
Algae have important ecological roles, including producing most of
the world’s oxygen and being the primary producers – the basis of the
food chain for all other life – in the ocean.
Algae are one of the important sources of food for fishes, aquatic
amphibian, mammals and other animals. Algae like Gracilaria and
Gelidium are used as food in coastal regions of India. Spirulina, a type of
blue-green algae is rich in proteins, vitamin B complex and minerals.
Powdered Spirulina is used in herbal tonics and biscuits.
In New Zealand, Denmark, France, Norway etc some algae like
sargassum, ascophyllum, marcocystis etc are used as fodder for animals.
Algae Chlorella Pyrenoidosa and Synechococcus are useful for
astronauts for the reason that these algae multiply rapidly and thus will
synthesize a rich harvest of food utilizing the carbon di oxide and
liberating sufficient oxygen as a byproduct for the use of astronauts.
Iodine obtained from kelps is used to prepare various anti-goitre
medicines.
Chlorellin, an antibiotic obtained from Chlorella, Cladophora and
Lyngbya possess anti-viral properties. Charales are useful in destructing
the mosquito larvae. Agar-Agar is used in laxatives. Carrageenan acts as
blood coagulant.
Some blue green algae, such as Anabaena, Nostoc, Aulorisa,
Tolypothrix etc are able to convert atmospheric nitrogen into molecular
nitrogen. Thus they act as nitrogen fixing agents to increase the fertility
of the soil.
PRESENCE OF ALGAE ON WATER BODIES AND THEIR HARMFUL
EFFECTS
Now let us come to the key point of this project ie. harmful effects
of algae. As told already it was really shocking to notice that most of the
water bodies around us are being spoiled due to the growth of algae. In
villages in olden days and even now in most of the rural areas ponds are
considered as the main source of water for various domestic uses. The
villagers keep these ponds clean. Towards the end of the summer the
remaining water in the ponds are pumped out and the bottom and sides
of the ponds are cleaned of all dirty materials, clay and even growing
vegetation. The monsoon rains fill the ponds and the water is used over
the year till next monsoon. As the time goes several under water plants
flourish in the pond and so the algae. Towards the beginning of summer
a green scum starts appearing over the pond water surface – the
Spirogyra. It is noticed that this scum causes some bad smell as well as
bad taste to the water. Hence it is a fact that the water contaminated
with algae becomes unfit for use.
Such growth of Spirogyra can be removed by skimming the floating
scum. But think if the algae grow in plenty to such an extent that it
becomes practically impossible or uneconomical to remove them. There
is no way out than to prevent the growth by continued filtering and
avoiding conditions favorable for the growth.
Harmful algal bloom is one of the severe conditions of spoilage of
water bodies by a type of algae called blue-green algae to which
references have already been made above. It was noticed that the water
of the Sreevaraham and Mithranandapuram temple ponds before
cleaning looked greenish brown and was having severe odor.
Blue-green algae:
Blue-green algae also known as Cyanobacteria or blue-green
bacteria, and Cyanophyta is a phylum of bacteria that obtain their energy
through photosynthesis. The name "Cyanobacteria" comes from the color
of the bacteria.
Blue-green algae can be considered as simple aquatic plants that
exist naturally in marine waters, rivers, lakes and ponds. When certain
conditions are present, such as high nutrient and light levels, these
organisms can reproduce rapidly. This dense growth of algae is called a
bloom. Some of these blooms are harmless, but when the blooming
organisms contain toxins, other noxious chemicals, pathogens or other
impacts to reaction or economic activities it is known as a harmful algal
bloom.
In addition to depleting the oxygen in water, the algae poison the
filter-feeding shellfish such as mussels and clams that consume them.
The shellfish in turn become poisonous to any animal, including humans
that eat them. Potentially fatal outbreaks of shellfish toxicity happen
every year, and people die, along with marine mammals, birds, fish and
higher invertebrates
As per recent news paper reports one of the Bengali mazdoor died
at Medical College, Thiruvananthapuram after eating clams caught from
the Kannanthura beach near Shanghumugham. It was also reported that
the clams became toxic due to “Kadal Kara” the local name for Toxic
Algal Bloom. Sometimes the algae directly release toxins into the
environment.
When the algae that cause toxic blooms are mostly varieties of red
algae, the name red tides is given for the deadly blooms.
Some algal blooms can look like foam or thick slurry. The blooms
can be blue, bright green, brown or red and may look paint floating on
the water. Some blooms may cause only discoloration of the water or
may not affect the appearance of the water.
Certain blue green algae produce toxins that could pose a health
risk to people and animals when they are exposed to them in large
enough quantities. Health effects could occur when surface scums or
water containing high levels of blue green algal toxins are swallowed or
through contact with the skin or when air borne droplets containing
toxins are inhaled while swimming, boating and skiing.
Blue-green algae that form harmful blooms have been known to
produce a wide array of neurotoxins, liver toxins, cell toxins and skin
irritants. Consumption of large amounts of these toxins by animals or
humans can result in muscle cramps, twitching, paralysis, cardiac or
respiratory difficulty, nausea, vomiting and liver failure. Skin irritants,
found in nearly all blue-green algae blooms, can produce symptoms
including skin irritation, rashes and gastrointestinal distress.
It is also reported that the most dominant blue-green algae viz
Microcystis, produces Microcystin, a liver toxin and skin irritant.
Bright green blooms are a result of Cyanobacteria or blue-green
algae such as Microcystis. Blooms may also consist of macroalgal (non-
phytoplanktonic) species. These blooms are recognizable by large blades
of algae that may wash up onto the shoreline
Freshwater algal blooms
On a smaller scale, algae are a pest in the tanks, ponds and lakes
used for fish farming. As in the ocean, algae can deplete the water of
oxygen and cause problems for fish. Algae can also overwhelm plants
and immobile animals, like corals, and clog up equipment. In swimming
pools, gardens, and bird baths algae are little more than unsightly, but in
aquaculture they are often a serious problem
Freshwater algal blooms are the result of an excess of nutrients,
particularly phosphorus. The excess of nutrients may originate from
fertilizers that are applied to land for agricultural or recreational
purposes; these nutrients can then enter watersheds through water
runoff. Excess carbon and nitrogen have also been suspected as causes.
When phosphates are introduced into water systems, higher
concentrations cause increased growth of algae and plants. Algae tend to
grow very quickly under high nutrient availability, but each alga is short-
lived, and the result is a high concentration of dead organic matter which
starts to decay. The decay process consumes dissolved oxygen in the
water, resulting in hypoxic conditions (oxygen depletion). Without
sufficient dissolved oxygen in the water, animals and plants may die off
in large numbers.
Blooms may be observed in freshwater aquariums when fish are
overfed and excess nutrients are not absorbed by plants. These are
generally harmful for fish, and the situation can be corrected by changing
the water in the tank and then reducing the amount of food given.
Algal blooms caused by blue-green algae and spirogyra are not
alike. Some times both are mistaken for each other. A comparison of
both is as given below.
Harmful Algal Bloom : Microcystis Muck : Cladophora or Spirogyra
Blooms tend to stay in water
column
Can wash up on shore in mats
Can produce liver, skin, or nervous Not known to produce toxins
system toxins
Blooms not known to harbor E. coli Mats (on beach and in water) have
contained E. coli
Peak growth often occurs late
summer
Peak growth often occurs early
summer
When blooms die, sink to bottom,
often responsible for
When blooms die, float to surface,
final location
depleted oxygen on bottom depends on wind and water bottom
circulation
Colonial (circular cells) Filamentous (end to end), branched
Grows in response to nutrients,
light
Grows in response to nutrients,
light
Planktonic (passively moves in
water)
Benthic (bottom dwelling)
Microalgae (microscopic cells) Macroalgae (grow up to 3 ft. long)
Other reasons for algal blooms:
Water is still and turbulence is low (lack of mixing)
Weather patterns are stable for a long time
Weather is warm
There is more sunlight
Shallow water bodies which allow more sunlight to pass to under
water
OBJECTIVE
Objective of this project is to have case study on harmful algal
blooms in fresh water ponds. More precisely, to study whether there is
any harmful effect due to the presence of algae and how the excessive
growth of algae has resulted in those ponds. Finally, to suggest some
methods to avoid the algal growth in fresh water ponds from the
knowledge acquired during case studies.
CASE STUDIES
I : Sreevaraham and Mithranandapuram Temple Ponds :
Sreevaraham temple pond is located on the Western side of the
Sreevaraham temple in Trivandrum. The pond has a ring road passing
almost all around except for the eastern side, where the temple is
located. The North, west and Southern sides of the pond are thickly
populated “Agraharams”. According to the residents all around the pond
has become a garbage dump and a breeding place of mosquitoes. It was
noted that the bad smell of water has rendered the living on the banks
much difficult. The Trivandrum Corporation has now took initiatives for
cleaning the pond and reclaiming the banks by constructing new
retaining walls.
Due to the damaged side walls all the waste water from the road
drain, houses around and the storm water simply rushes into the pond.
When we visited the pond almost 90 % of the water has been
pumped out and even then I could see the algal scum floating on the
water. The mud at the bottom of the pond was simply black in color and I
could not stand the bad smell that emerged from the pond. On enquiry
with the locals it was revealed that the residents all around used to drain
their waste water into the side drains of the road which in turn drained
into the pond on several occasions. On analysis of the water sample
collected from the pond, the presence of Spirogyra and Blue-Green algae
was released.
It is understood that the waste water mainly consisted of soap
waste which is a good source of phosphates that has catalyzed the
growth of algae in plenty. The black mud at the bottom is generated from
the sedimentation of storm water and from the sedimentation of dead
algae.
It was told that, during historic periods, the pond had a drain which
constantly drained the water from pond above a particular level. People
used to bath in this pond. No house hold waste was drained in to the
pond. The water had never been spoiled like now. Now the case is
reverse: The heavy load of waste/nutrients and blocked drain has made
the water more concentrated of nutrients suitable for the growth of
algae. The cleaning works initiated by the Corporation authorities are still
going on.
The Mithranandapuram temple pond located just 1 km north of the
Sreevaraham pond, by the side of the West Fort Street (Airport Road). In
contrast to Sreevaraham pond this one is a confined one with less
number of residences around. But the main road to the Airport is lying on
the Northern side. All the waste water flows into the pond during rains,
due to the dilapidated condition of side walls. There is no proper cleaning
and there is no drain even for draining the excess waster. The
Corporation has cleaned this pond and the construction of side walls is
yet to be taken up. But after cleaning the water is now clear and has no
smell or odor.
II : A Village pond by the side of NH-47 at Marutha Road near
Palghat :
When we were returning from Ooty we happened to notice a pond
by the side of the road. We alighted there to have a look at the pond.
Some local people also came around. This pond is located at corner of
large extent of paddy fields. At first, we could not see any water in the
pond. What we could see was only a thick scum of algae. We just
skimmed a portion and could see the greenish brown water under neath.
The locals were saying that they used to take bath in this pond years
back. But due to the construction of NH bye pass the drains have been
blocked. There is no culvert. The excess quantity of fertilizers used in the
paddy fields have drained into this pond. There is no side wall for this
pond. The scum mainly consisted of Spirogyra. It was told that the locals
have urged the Panchayat authorities for cleaning the pond at regular
intervals. The locals also warned us not to venture into the pond as
contact with the water may cause itching in the skin.
III : Pond at Alapuram Children's Park and Boat Club, near
Muttada, Trivandrum :
This pond is located near Muttada. The pond was in a neglected
condition years back. It was told that this pond is once renovated and
side walls we could see was constructed then, about 7 years back. Even
then what we could see at the pond was deep green water. Surprisingly
we could also see children swimming in the pond with any inconvenience
of itching or any such discomfort. We collected samples and even simply
looking at the sample we could see the algae floating in it. The sample
was kept still for some days in ventilated bottles. The algae got
sedimented at the bottom. On analysis, this sample showed the presence
of blue green algae.
It was noticed that this pond does not have any drain facility. So
the rain water and spring water entering the pond is held there itself
making the water concentrated of nutrients making situation favorable
for the algal growth. Sufficient sunlight is also available. How ever the
water in this pond is not potable due to the presence of algae, its smell
and odor.
IV : Guruvayoor temple pond :
On contrast to all the above we could find crystal clear water in this
pond. My father's sister is living near the temple. With the help of uncle
we visited the temple authorities to know how they keep the water clean.
We noticed that lot of people are taking bath in the pond and the pond is
having no drain at all.
The authorities explained that they have installed a filtering plant
by the side of the pond. This was installed about 25 years back. Before
that the water in the pond was green in color like any other temple pond
we could see along the country. The water from the pond is pumped into
the plant where the algae is filtered to a large extent. Then the water is
chlorinated to deodorize and for decolorising. This cleaned water is let
back into the pond through another end. This process keeps the water
almost crystal clear. The authorities also told that if the plant is shut
down for about a week or more the water is seen to turn green.
In addition, the authorities have introduced restriction to the usage
of soap and oil in the pond while bathing. Dumping of garbage is strictly
prohibited. Good side walls prevent entry of either waste water or storm
water during rains.
INFERENCES
Algae is found in almost all water bodies.
Algae thrive best in the presence of Phosphates and Nitrates.
Algae thrive best where good sunlight is available.
Algal blooms render the water bodies unfit for human use.
Proper filtration of suspended algae could keep the water clean.
Toxic algal blooms can cause skin irritation and could also be fatal.
RECOMMENDATIONS
Water is very precious. So we should preserve what ever sources of
water is available to us. We have seen that uncontrolled growth of algae
in fresh water will render it unfit for domestic use. There are other
activities also which contaminate the fresh water sources. How ever we
are at present concerned about controlling algal growth that may
contaminate the water sources.
From the case studies and other readings, a part of which is
discussed in brief in paras above, the following recommendations are put
forth for preserving the fresh water sources.
Inflow of any kind of surface water into the ponds or lakes which is
a source of fresh water must be checked at any cost.
Use of soaps and detergents, which are sources of phosphates,
must be discouraged in the pond.
Drains from paddy fields and other cultivated areas shall not be
allowed to discharge into the fresh water sources such as ponds lakes
etc. This will reduce the inflow of nitrogenous and phospahatic salts into
them.
The ponds shall have facility for constantly draining the excess
water above a particular level. The ponds will have springs from were
water is incoming. This spring water may contain some minerals which
we cannot control effectively. So the overflow drain will help in keeping
the salt/algal concentration to a minimum.
Ponds shall be cleaned at regular intervals preferably by the end of
summer by pumping out the water and removing the mud and other
debris collected at the bottom. Dead or decaying leaves increase the
nutritional value of the water in the pond providing a rich source of
nutrition to algae.
Growing fishes is also a control method. The fishes will consume
most of the floating algal matter thus keeping the water clean.
Growing aquatic plants that can use up pond nutrients will also
reduce the risk of algal blooms.
Chemically treating the pond with algaecide can also help
effectively put an end to algal growth. But the that algaecide can have
negative effect on aquatic life. One should ensure that the pond has
proper filtration systems to remove dead algae and should make sure
that the pond does not have aquatic plants and wildlife, as they can be
severely affected by algaecide.
Beneficial bacterial used on a regular basic can effectively help in
natural algae control on most algae types. In addition, beneficial bacteria
can also help in reducing water order, improving health of fish and in
controlling mud/sludge in ponds.
Having rocks and stones in the pond can aid in the growth of
beneficial bacteria. But such stones have high risk on ponds supposed to
be used as swimming pools.
BIBLIOGRAPHY
1. WEBSITES : www.wikipedia.org www.eHow.com www.igin.com aquaticpath.umd.edu/toxalg/ www.waterencyclopedia.com › A-Bi www.kdheks.gov/ - United States (Kansas Department of health and environment)
2. BOOKS :
Exploring biology by Sanjay Sharma and Sudhakar Banerjee, Arihant Publications NCERT Biology Text for class XI A text book of biology for XI by Dr. J.P. Sharma, Laxmi Publications