Reef Ecosystems And Their Decline

Jean Pierre Ledee CIAM 6117 – 0U1

Prof. Loretta Robertson, PhD

OVERVIEW

• ECOSYSTEM

• CURRENT DANGERS

• CLIMATE CHANGE

• BLEACHING

• OVERFISHING

• PUERTO RICO

• REMEDY

• QUESTIONS

• REFERENCES

ECOSYSTEM

• FOR MILLIONS OF YEARS, THE

REEFS HAVE BEEN IN A STEADY

BALANCE BETWEEN ITS

ENVIRONMENT IN CHEMICAL AND

PHYSICAL FORM.

CLIMATE CHANGE

• WARMER WATER TEMPERATURES

BROUGHT ON BY CLIMATE CHANGE

STRESS CORALS BECAUSE THEY ARE

VERY SENSITIVE TO CHANGES IN

TEMPERATURE.

• IF WATER TEMPERATURES STAY HIGHER

THAN USUAL FOR MANY WEEKS, THE

ZOOXANTHELLAE THEY DEPEND ON

FOR SOME OF THEIR FOOD LEAVE

THEIR TISSUE.

• WITHOUT ZOOXANTHELLAE, CORALS

TURN WHITE BECAUSE

ZOOXANTHELLAE GIVE CORALS THEIR

COLOR.

• BLEACHED CORALS ARE WEAK AND

LESS ABLE TO COMBAT DISEASE.

CLIMATE CHANGE

• MUCH OF THE CARBON DIOXIDE THAT

ENTERS THE ATMOSPHERE DISSOLVES

INTO THE OCEAN.

• THE OCEANS HAVE ABSORBED ABOUT

1/3 OF THE CARBON DIOXIDE

PRODUCED FROM HUMAN ACTIVITIES

SINCE THE 1800’S.

• AS CARBON DIOXIDE IN THE OCEAN

INCREASES, OCEAN PH DECREASES

OR BECOMES MORE ACIDIC.

• WITH OCEAN ACIDIFICATION, CORALS

CANNOT ABSORB THE CALCIUM

CARBONATE THEY NEED TO MAINTAIN

THEIR SKELETONS.

CLIMATE CHANGE

Time pH pH change relative

to pre-industrial

H+ concentration

change

relative to pre-

industrial

Pre-industrial (18th

century) 8.179

Recent past (1990s) 8.104 −0.075 + 18.9%

Present levels ~8.069 −0.11 + 28.8%

2050 (2×CO

2 = 560 ppm) 7.949 −0.230 + 69.8%

2100 (IS92a)[34]

7.824 −0.355 + 126.5%

CLIMATE CHANGE

CLIMATE CHANGE

• BLEACHING

OVERFISHING

• ALL ANIMALS THAT ARE FUNDAMENTALLY INTEGRAL TO

THE REEFS MAKE UP A CHAIN THAT STOPS WORKING

CORRECTLY IF ONE OF THE COMPONENTS IS MISSING.

• EACH ANIMAL FEEDS ON OTHER ANIMALS AND IS AT THE

SAME TIME FOOD FOR EVEN GREATER ONES.

• GENERALLY, LARGE CARNIVOROUS ANIMALS FEED ON

THE ONES THAT DIRECTLY EAT PARTS OF THE CORALS.

THIS MAINTAINS A WORKING BALANCE BETWEEN ALL.

OVERFISHING

OVERFISHING

• THE INTRODUCTION OF HUMANS TO

THE EQUATION HAS GREATLY

AFFECTED THIS FLOW.

• BY OVERFISHING SPECIFIC SPECIES

OF FISH, WE GREATLY UNBALANCE

THE FOOD CHAIN IN THE REEFS.

• HUMANS MOSTLY OVERFISH THOSE

THAT ARE HIGH ON THE FOOD

CHAIN BECAUSE OF THEIR SIZE

AND QUALITY OF THE MEAT.

OVERFISHING

• THIS IN TURN CAUSES AN INCREASE ON THOSE THAT

FEED OFF OF THE CORALS AND DAMAGES THE

UNDERWATER LIVING HABITAT.

• BY ELIMINATING THE HABITAT, THE ENTIRE CHAIN IS

BROKEN BY DECREASING THE TOTAL POPULATION IN

THE LONG RUN.

PUERTO RICO

• BLEACHING

• 1987 - MAJOR BLEACHING IN THE CARIBBEAN

(HIGH TEMPERATURES)

• 1989 – MINOR BLEACHING (HURRICANE HUGO)

• 1990 - MOST SEVERE BLEACHING EVER

EXPERIENCED IN THE WESTERN NORTH ATLANTIC

• 1995 – SEVERE AND WIDESPREAD BLEACHING

THROUGHOUT CARIBBEAN.

• 1998 – STRONGEST BLEACHING EVENT IN PUERTO

RICO

PUERTO RICO

REMEDY

• HOW TO FIX THE PROBLEM

• BETTER REGULATIONS NEED TO BE

IMPLEMENTED TO CONTROL THE AMOUNT OF

FISHING DONE THROUGHOUT THE WORLD.

• BETTER MANAGEMENT OF THE CURRENT

REGULATIONS SINCE MOST OF THESE ARE

IGNORED OR NOT ATTENDED AS THEY

SHOULD BE.

REMEDY

• CREATE MORE UNDERWATER

SANCTUARIES OR PROTECTED

ENVIRONMENTS TO PROMOTE AND

HELP IN THE CREATION OF NEW

REEFS AND EXPANSION OR

HEALING OF CURRENT ONES.

• MAKE THE PROBLEM VISIBLE TO

THE POPULATION SO EVERY

INDIVIDUAL UNDERSTANDS THE

SITUATION AND IS MOTIVATED TO

HELP.

QUESTIONS

• CAN THE PROCESS OF CLIMATE CHANGE BE STOPPED? CAN IT

BE REVERSED?

• CAN BLEACHING OF THE CORALS BE FIXED?

• IS THERE A WAY TO ACCELERATE THE GROWTH OF CORALS?

• CAN WE CONTROL OVERFISHING WITHOUT HINDERING THE

GLOBAL ECONOMY?

• IS THERE A WAY TO BETTER PROTECT AND MAINTAIN THE

UNDERWATER HABITAT?

• Coral Reefs and Climate Change - How Does Climate Change Affect Coral Reefs - Teach Ocean Science. (N.D.). Retrieved September 20, 2015.

• The State of Coral Reef Ecosystems of Puerto Rico – National Oceanic and Atmospheric Administration. Retrieved September 20, 2015.

• Climate Change and Coral Bleaching In Puerto Rico: Efforts and Challenges – Puerto Rico Department of Natural and Environmental Resources. Retrieved September 20, 2015.

• Velazco, A. (2003, June 18). Climate Change And Coral Bleaching In Puerto Rico: Efforts And Challenges. Retrieved September 20, 2015.

• Using Data To Identify Hot Spots And Predict Bleaching Events – EarthLabs. Retrieved September 20, 2015.

• Meyers, J. (2009, October 12). Global Warming and Coral Bleaching. Retrieved September 20, 2015.

REFERENCES