algal bloom

1. Jayanta S.Tiple
B.F.Sc. 3rd
year
Algal Bloom

2. Content
• Introduction
• HAB’S
• In India
• World Wide effect of HAB’s
• Reasons of increasing HAB’s
• Images of some Algal Bloom
• Some spp. of HABs
• Cyanobacteria
• Effect of algal bloom.
• Control method

3. Algal Bloom
• An algal bloom is a rapid increase in the popullation of
algae in an aquatic system.
• Algal blooms may occur in freshwater as well as marine
environments.
• Result of an excess of nutrients (particularly p and n).
• Their growth - cause for other plants to die.

4. Algal Bloom

5. Harmful algal blooms
A harmful algal blooms is an algal bloom that causes
negative impacts to aquatic organisms via production of
natural toxins, mechanical damage to aquatic organism.
HABs are often associated with large-scale marine
mortality events and have been associated with various
types of shellfish poisonings and also fin fishes and other
aquatic organisms .

6. In India
• Researchers have found toxic bloom has increased
around 15 percent over the 12 years in indian seas.
• There was 80 harmful bloom recorded between the
1998-2010 in indian water.
Research data was generated by- K.B Padmakumar & V.N
Sanjeevan (centre for marine living resources &
Ecology,kochi)
1st
recorded observation on algal bloom in india was in
1908.

7. Worldwide Effects of HAB’sWorldwide Effects of HAB’s
Light penetration levels in water decrease altering
photosynthesis rate.
Algal blooms may be harmful to seagrass and coral
reef ecosystems and the connected food webs.
Shellfish may accumulate algal toxins by feeding
on the toxic phytoplankton resulting in fish kills,
marine mammal distress, human illness and
possible death.

8. Reasons for Increase in HAB’sReasons for Increase in HAB’s
 Global climate changes producing wider ranges
for some species.
 Human contributions of increased nutrients and
pollution in coastal waters and also fresh waters.
 Changes in local ecosystems that may allow
exotic species to thrive if introduced.

9. Continue..
 Upwelling.
 Formation of mud banks.
 Nutrients discharge on sea or fresh water
through river.

10. Eutrophication means of process where by water bodies receive
excessive amounts of nutrients, which results in excessive plant
growth and formed algal bloom.

14. IN AQUACULTURE

16.  Factors that can contribute to HABs
include:

Excess nutrients (e.g. phosphorus or nitrogen)

Sunlight

Low-water levels or low-flow conditions

Calm water (low-wind conditions)
 Warmer temperatures

17. Images
Freshwater algal blooms A red tide

18. Some HAB’s
• Cyanobacteria (blue-green algae)
• Redtides - neurotoxic shellfish poisoning
• Ciguatera-Gambierdiscus toxicus
• Alexandrium
• Gymnodium
• Dynophysis
• Coolia monotis
• Prorocentrum lima.

19. Harmful effect of algal bloom
• Changes in levels of chemicals such as nitrogen and
phosphorus from fertilizer, in the water.
• Algal blooms can deplete the oxygen and block the
sunlight that other organisms need to live.
• And some can produce toxins that are harmful to the
health of the environment- plants, animals, and people etc.
• Aquaculture industries.

21. PROBLEMS

24. PREVENTION

25. Control method
• Biological- Bacteria(Gymnodinium mikimotoi ),
Virus, Bivalves, zooplankton etc.
• Chemical- Copper sulfate, Alum etc.
• Physical

27. EXAMPLE

28. Thank You