Describing different way on how effluents released from thermal plants into the seas/ocean can have immense negative effect on the marine fauna and flora.

1. THE EFFECTS OF THERMAL POLLUTION
ON MARINE LIFE
By Surabhi Tanwar

4. 1) DECREASE IN DO (Dissolved Oxygen) LEVELS:
• Cold water contains more oxygen
than hot water so increases in
temperature also decrease the
oxygen-carrying capacity of water.
• In addition, raising the water
temperature increases the
decomposition rate of organic
matter in water, which also depletes
dissolved oxygen.
• These decreases in the oxygen
content of the water occur at the
same time that the metabolic rates
of the aquatic organisms, which are
dependent on a sufficient oxygen
supply, are rising because of the
increasing temperature.

5. • Ocean invertebrates, fish and marine reptiles are obligate
poikilotherms -- their body temperatures depend entirely on the
surrounding water.
• Each species is adapted to a single range of temperatures and many
pass through several different life stages, each with an individual
range of tolerance. The ocean's vast populations of microbes, fungi
and sea plants also rely on narrow temperature ranges for optimal
growth.
• Thermal pollution often temporarily increases aquatic plant
populations. Other life forms, including microbes and animals, move
into these regions to exploit the higher oxygen levels, but when
photosynthesis stops at night or upon the death of plants, dissolved
oxygen levels plummet, leading to massive animal die-offs. Excess
heat can also cause unnaturally large microbial blooms, which kill
animals by depleting local oxygen or producing toxins.

7. • Unnatural warmth and cold can also
delay and redirect migration, influence
when and whether breeding occurs, and
decrease survival of young in marine
mammal, reptile and bird populations.
• Heat pollution that leads to an
overabundance of organisms in a region
can draw in excessive numbers of
creatures that feed on them, while
depletion of prey populations by heat
stress forces their predators to encroach
on regions outside their normal range.
Both situations lead to unnatural
competition between and within species.
2) MIGRATION :

9. • A sudden thermal shock can result in
mass killings of fish, insects, plants or
amphibians.
• Hotter water may prove favorable
for some species while it could be
lethal for other species. Small water
temperature increases the level of
activity while higher temperature
decreases the level of activity.
• Many aquatic species are sensitive
to small temperature changes such
as one degree Celsius that can
cause significant changes in
organism metabolism and other
adverse cellular biology effects.
3) ECOLOGICAL IMPACT :

10. • A significant halt in the reproduction
of marine wildlife (although this may
be true, reproduction can still occur
between fish – but the likelihood of
defects in newborns is significantly
higher) can happen due to
increasing temperatures as
reproduction can happen with in
certain range of temperature.
• Excessive temperature can cause
the release of immature eggs or can
prevent normal development of
certain eggs.
4) AFFECT ON REPRODUCTIVE SYSTEM :

12. • Outside of ideal temperatures,
digestive enzymes begin to fail,
altering organisms' rate of growth
and ultimate size.
• Altered temperature can cause the
need for more food and farther
travel farther to find it, placing stress
on surrounding populations as
hungry interlopers encroach.
• Excess heat can confuse animals'
ability to determine season and
even direction.
→ It is also important to know that, thermal pollution can also
trigger malnutrition in the affected organisms. Increase in the
water temperature interferes with enzymes which are
responsible for breaking down of lipids.
5) DIGESTIVE SYSTEM :

14. • A nuclear power-generating station on Nanwan Bay in Taiwan
caused bleaching of corals in the vicinity of the discharge
channel when the plant first began operation in 1988.
• Studies of the coral Acropora grandis in 1988 showed that the
coral was bleached within two days of exposure to temperatures
of 91.4°F.
• In 1990 samples of coral taken from the same area did not start
bleaching until six days after exposure to the same temperature. It
appears that the thermotolerance of these corals was enhanced
by the production of heat-shock proteins that help to protect
many organisms from potentially damaging changes in
temperature.

15. Marine
 http://animals.pawnation.com/effects-thermal-pollution-marine-
life-7712.html
 http://everydaylife.globalpost.com/effects-thermal-pollution-
marine-life-40307.html
 http://www.conserve-energy-future.com/causes-and-effects-of-
thermal-pollution.php
 http://www.slideshare.net/amba_slide/marine-pollution-8524112
 http://www.slideshare.net/nileshjakher/thermal-pollution-16258502
 http://www.powershow.com/view/1ac5e3-
ODYxY/Thermal_Pollution_powerpoint_ppt_presentation

16. Presentation by: Surabhi Tanwar
Student of Masters in Environmental
Science- Institute of Science, Mumbai