Transcript Coral - Fiji National University | E

EDU 711
Science and Technology
Assignment 2
SEREIMA BANUVE
2012000688
SECTION: 302
TOPIC
CLIMATE CHANGE- CORAL BLEACHING
Source: David Burdick, NOAA.
WHAT ARE CORAL?
•
•
•
•
•
•
•
•
Corals are marine invertebrates living in compact colonies of many
identical individual "polyps".
composed of tiny, fragile animals called coral polyps
Have tiny plant like organism living in their tissues
Cannot survive without the microscopic algae zooxanthellaephotosynthetic algae live inside the polyps tissue.
Coral give the algae a home in return the algae provide the coral with
food.
Also called the tropical rainforest of the oceans.
Coral are animals.
zooxanthellae provide up to 90 per cent of the energy corals require to
grow and reproduce.
Continues……..
Source:
www.ourbreathingplanet.com
Source:wikipedia.org
SOME OF THE CORALS FOUND IN FIJI WATER
Found in Beqa
Lagoon
Found in Bligh Water
Source:
www.scubasue.com
Source:www.divemistres
s.net
Found in
the coral
coast
Source: coralcoastfiji.org
Source:www.uwphotog
raphyguide.com -
Coral Polyps- zooxanthella
SOURCE:
extrememarine.org.uk
Zooxanthellae algae require
sunlight for photosynthesis, and
coral reefs usually begin to form
in clear, shallow waters near land
because water gradually filters
out sunlight with depth.
Tiny plant cells called zooxanthellae live within
most types of coral polyps. They provide the
.
coral with foods resulting from photosynthesis
Source: oceanservice.noaa.gov
Contributed by TammyG
Types of Coral
• Two main categories of corals which are hard corals and soft
corals
• Examples of hard corals include: brain, star, staghorn, Elkhorn,
and pillar. Soft corals include: sea fans, sea rods, sea whips and
sea plumes.
Hard corals
Source:en.wikipedia.org
Mushroom Coral
Photo Credit:
Courtesy NOAA
SOME HARD CORAL IN FIJI
SOURCE:
http://www.liveaquari
a.com: (Acropora sp.)
SOURCE:
http://www.liveaqu
aria.com:
(Acropora
hyacinthus
Hard coral are marine corals that generate a hard skeleton
SOFT CORAL
Sea Fern
Source:Andrew David,
NOAA/NMFS/SEFSC
Panama
Foliase (Cabbage) Coral
Photo Credit: Chuck Savall, ICRIN
Source: Gorgonian Fan coral:
Gorgonia ventalina on “La
Jardinera”
www.uwphotographyguide.com -
Soft Coral found in Fiji
Source:www.allposters.c
om
Source:liveaboardadventures.co
m
Soft corals are soft bodies made up of a large number
of polyps connected by fleshy tissue. They lack the
limestone skeleton found on their relatives, the hard
coral. The term 'soft' is a bit misleading because
these corals have numerous tiny, needle-like spicules
in their tissues.
So What is
Coral
Bleaching?
• Coral bleaching is a stress condition in reef corals
that involves a breakdown of the symbiotic
relationship between corals and unicellular algae
(zooxanthellae).
• These microscopic plants live within the coral tissue
and provide the coral with food for growth and their
normal healthy colour.
• symptoms of bleaching include a gradual loss of colour
as zooxanthellae are expelled from the coral tissue,
sometimes leaving corals bone white
• Most reef-building corals normally contain around 1-5
x 106 zooxanthellae cm-2 of live surface tissue and 210 pg of chlorophyll a per zooxanthella. When corals
bleach they commonly lose 60-90% of their
zooxanthellae and each zooxanthella may lose 50-80%
of its photosynthetic pigments (Glynn 1996).
Continu…..
Source:en.wikipedia.
org
source: J. Roff
Source: scienceyoucanlove.tumblr.com
Source:www.peoplean
dtheplanet.com
Source:www.treehugger.co
m:
Source: wind.jmu.edu
Source:
www.globalwarmingimages.
net
What causes coral bleaching?
• environmental stressors such as pollution, oil spills,
•
increased sedimentation, changes in salinity, low oxygen, or disease.
Primary cause of coral bleaching is increased sea temperatures.
Corals are very sensitive animals so water temperatures need only
increase 1-2 degrees Celsius above normal levels for bleaching to
occur. The corals are still alive after bleaching but begin to starve.
Most corals struggle to survive without their zooxanthellae. If the
stressful conditions return to normal rather quickly, the corals can
regain or regrow their zooxanthellae and survive. If the stressors
are prolonged, the corals are more susceptible to disease,
predation, and death because they are without an important energy
source.
(source :http://www.reefcheckhawaii.org/eyesofthereefBleach.htm)
• a rise in sea surface temperature and loses the symbiotic algae that
provide it with color and nutrition.
Fresh Water Dilution
• Rapid dilution of reef waters from storm-generated
precipitation and runoff has been demonstrated to cause coral
reef bleaching. Generally, such bleaching events are rare and
confined to relatively small, near shore areas.
• (http://www.marinebiology.org/coralbleaching.htm)
Solar Irradiance
• Bleaching during the summer months, during seasonal
temperature and irradiance maxima often occurs
disproportionately in shallow-living corals and on the
exposed summits of colonies. Solar radiation has been
suspected to play a role in coral bleaching. Both
photosyntheticaly active radiation (PAR, 400-700nm) and
ultraviolet radiation (UVR, 280-400nm) have been
implicated in bleaching.
• (http://www.marinebiology.org/coralbleaching.htm)
Rising sea levels: Global sea levels may rise by more than 60
centimeters during the next 100 years due to the melting of
glaciers and polar ice, and thermal expansion of warmer water.
Rising water levels will have serious impacts on marine
ecosystems. The amount of light reaching offshore plants and
algae dependent on photosynthesis could be reduced, while
coastal habitats are already being flooded.
Chemical Pollution
• Agriculture and industry release a variety of chemicals into
coastal waters. Pesticides and fertilizers used in agricultural
development projects are carried in run off to sea and have
been known to take part in coral reef destruction. Pesticides can
destroy or damage zooplankton or reef communities. They cause
further damage by accumulating in animal tissue and may affect
physiological processes. Herbicides may interfere with the basic
food chain by destroying or damaging zooxanthallae in coral,
free living phytoplankton, algal or sea grass communities.
Source: http://www.gbrmpa.gov.au
Coral bleaching in Fiji
• Gregor Hodgson, founder of Reef Check, a volunteer
organization that provides an annual survey of coral reefs, said
bleaching has occurred in approximately 65 percent of Fiji's
reefs. About 15 percent of them are dead.
• (By Environmental News Network staff, April 26, 2000
Web posted at: 12:03 p.m. EDT (1603 GMT)
• Coral bleaching in the Somosomo Strait - Fiji Islands. April 2000
Photo by James Wiseman
Source:Fiji. © Cat
Holloway / WWF-Canon
What impact does Coral Bleaching have on Fiji?
•
•
•
•
•
According to Dr Robin Cumming, a biology lecturer at USP,
Fiji's reefs were affected by bleaching in 1998 and in 2000 with
some areas worse hit than others.
Fiji is a country that is highly dependent on tourism for its
income so coral bleaching affect economy.
Destroy many marine life habitats
Destroy what need to protect us from tidal waves and tsunami.
Economy breakdown- attract a lot of tourist.
Impact of Coral Bleaching on the Pacific Island and
the World.
• In the Pacific Islands, collaboration with Hawai`i Conservation
Alliance and climate researchers at the University of Hawai`i’s
International Pacific Research Center, the Department of
Geography and many other Departments. collaborations are
aimed at assessing historic climate trends and promoting the
development of regional climate models that will aid in
estimating future climate conditions in the Pacific Islands.
• (http://www.fws.gov/pacific/climatechange/changepi.html)
•
•
•
Over 60 cases of coral bleaching have been found in the world since
the 1980s, they have been spotted in French Polynesia, the
Caribbean, Palau, Australia, and the eastern Pacific. Most of the
reported bleaching usually happens during the summer or at the end
of an extended period of warm temperatures (Buchheim 1998).
El Niño is the oscillations in the ocean and atmosphere systems in
the tropical Pacific Ocean. Some years El Niño is more severe than
in other years. At its severest, temperatures can rise up to 7 to
8°C. Such a high rise in temperature devastated the reefs in the
east Pacific. 95% of the coral reefs in Galapagos Island were
destroyed due to this wave of climate extremity. El Niño events are
found to occur every 7 to 8 years, research indicates that they now
occur much more frequently at anywhere from every 3 to 5 years.
This increase in frequency is attributable to climate change. Global
warming is the cause of an increasing number of cases of coral
bleaching all over the world. It is important to understand that the
actions taken on one side of the planet can have devastating
consequences on the ecosystems located on the other side of the
planet.
(http://sitemaker.umich.edu/gc2sec7labgroup3/climate_change)
Predicted hotspots for potential coral bleaching
and global warming. Graph provided
by NOAA satelite data and represents
predicted anomolies from mean sea
surface temperatures. Color bars
represent .25 degrees celcius temperature
anomolies. (White is normal, Red is +5 degrees
celcius warmer
SOURCE: http://www.gbrmpa.gov.au
In 1998, there was a global mass bleaching event where 50 per
cent of the reefs on the Great Barrier Reef suffered
bleaching. During this time, sea temperatures on the Great
Barrier Reef were the highest ever recorded.
Mass bleaching also occurred in 2002, with 60 per cent of
reefs were affected. This was the largest coral bleaching event
on record. Two periods of hot weather resulted in sea surface
temperatures a few degrees centigrade higher than long-term
summer maxima.
In both events, about five per cent of the Great Barrier Reef's
coral reefs were severely damaged.
Source:www.oceanclimatechange.org.au
CAN CORAL SURVIVE BLEACHING
Does the coral have any hope?
• Australian scientists have found that corals contain a kind of
sunblock called fluorescent pigments. These pigments form a
kind of shield around the zooxanthellae and protect them from
the harmful effects of sunlight at high temperatures. The
pigments change the harmful UV and blue wavelengths in
sunlight to softer, lower energy wavelengths like green and
yellow.
• Fluorescent corals survive bleaching events better than nonfluorescent corals, and every species of coral has some varieties
that have fluorescent pigments. Over time, more fluorescent
pigments may develop to protect the corals. Even though nonfluorescent varieties may die out, there will be some corals that
have the fluorescent pigments and therefore may survive.
• If a channel of cold water constantly runs through the warm
water, thus keeping the zooxanthellae cool, then those corals
can survive. Another way in which corals can survive is just by
being tougher than others, in the same way that some people are
always healthy while other people are always sick.
• (http://www.science.org.au/nova/076/076key.html)
Some possible solution
•
•
•
Create effective marine protected areas (MPAs). Create MPAs in areas
that are less prone to bleaching events because of local cold-water
currents.
Lessen other pressures on coral reefs. Reefs with fewer stresses will be
more likely to recover from coral bleaching and adapt to increased
temperatures. Countries and communities need to enforce laws against coral
destruction, as well as control pollutants, and promote sources of
construction material other than coral. Controlling coastal development
through an Integrated Coastal Zone Management (ICZM) strategy can help
protect reefs from long-term stresses.
Adopt policies and treaties to reduce greenhouse gas emissions and
climate change. The reduction of greenhouse gases will decrease the
severity of global climate change. All countries are encouraged to support,
ratify and implement the Kyoto Climate Change Convention. All countries are
also encouraged to participate in the work of the UN Framework Convention
on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate
Change ( PIPCC).
(http://www.coral.org/node/126)
• Protect and enhance ecosystems that absorb greenhouse gases.
The loss of some ecosystems, especially forests and wetlands,
contributes a significant amount of carbon dioxide and other
greenhouse gases to the atmosphere. Governments can mitigate
the severity of climate change by protecting and enhancing
these ecosystems, a strategy known as natural carbon
sequestration. Natural carbon sequestration is the process of
removing carbon dioxide from the atmosphere by enhancing
ecosystems, such as forests, that absorb greenhouse gases.
Carbon sequestration should be considered as a primary
management strategy.
(source: http://www.coral.org/node/126)
MY OWN VIEW
• Actually it was interesting to learn more about our ecosystem
especially Coral. My own view is that we need to keep our Oceans
free from all hazzards since for us here in Fiji, Coral is a source
of income. Ask me why? Because one of our most source of
economy is tourism and this natural beauty coral have attract
them to our shore. Tourist sometimes realise the beauty of Fiji
depend on our environment. My younger brother is a diving
instructor and he always says that underneath the ocean is
“Paradise”. Coral suffer because of this bleaching. We need to
stop all this from happening since Coral plays an important role
in our Ocean.
 It’s the habitat of our friends the marine life
 Beautification of there world- as we beautify ours with flowers.
 Protect us from tidal waves, imagine if there was no coral- there
are soldiers guarding our shores.
And a question I am
asking…..
What else can we do
to minimize this
issue?
CONCLUSION
• If a global warming trend impacts on shallow tropical and
subtropical seas, we may expect an increase in the frequency,
severity and scale of coral reef bleaching. Coral mortality could
exceed 95% regionally with species extinctions. A conservative
temperature increase of 1-2 degrees C would cause regions
between 20-30 degrees N to experience sustained warming that
falls within the lethal limits of most reef-building coral species.
In conjunction with sea temperature rise would be a sea level
rise, and it has been suggested that sea level rise would
suppress coral growth or kill many corals through drowning or
lower light levels. Some coral populations and their
endosymbiotic zooxanthellae may be able to adapt to the
extreme conditions predicted during global climate change.
Refuges in benign habitats, such as deep, sunlit reef substrates,
oceanic shoals and relatively high latitude locations, might exist,
but widespread coral mortality and reef decline would be
expected in shallow reef zones in most low latitude. Even if
significant sea warming and elevated irradiance levels do not
occur, coral reef degradation from anthropogenic pollution and
overexploitation will still continue, a result of unrelenting human
population growth