the tropical coral reefs - uab barcelona › pub › tfg › 2014 › 119242 › tfg... · the...

Local and 

Fisheries

Overfishingof hervibores

Destructivefishing

ExplosivesCianureTrawling

More seaweedsTHE TROPICAL CORAL REEFS

The tropical coral reefs are global centers of biodiversity, andthe most widely distributed reefs (Fig. 1). They are beingdegraded by several factors both direct human impacts such

- Beatriz Marín Díaz – Biologia Ambiental – Universitat Autònoma de Barcelona -

Excessivesedimentation

anthropogenic pressures

Climate

Oceantemperatures

increase

Increase in tropical storms and hurricanes

Rising sea level

Coral bleaching

Habitatdestruction

Trawling 

Coastal developement

• Tourism, edification

Contamination

• Agricultural and industry spillsTROPICAL CORAL REEF 

THREATS

degraded by several factors, both direct human impacts suchas climate change.

Zooxanthellae Coral

Aliment from photosynthesis, oxygen and calcification

Nutrients and protection

Coral species are long‐lived and slow growing, so damagesare often important.

Tropical region of western Atlantic

Indo‐Pacific region

Fig. 1. Distribution of tropical coral reefs [1]

BIODIVERSITY

Most diverse and complex communities of the planet,mainly fish and invertebrates

ESTATE OF THE REEFS

2008 data [2]:

19% of the original area is lost 15% are in critical state 20% are threatened 46% are recovering or in good state

INTERACTION BETWEEN THREATS AND EFFECTS

Climate global change

CO2

increase

Coral bleaching

Coral diseases

Ocean acidification

Population increase

( ff ll)

Decrease fish population

Hunger 

Sedimentation

46% are recovering or in good state

2011 data [3]:

25‐30% of world coral reef have been degraded

• Include between 1/3 and 1/4 of themarine species.

• Some studies report that this biodiversity is beingunderestimated.

• Almost 1/3 of coral species are endangered.

(affects all)

Algae cover 

Fisheries

Global climate change

Temperature increase

CO2 increase

Increase of oceans temperatures

Tropical storms

Increase of sea level

Coral bleaching

Diseases, plagues 

Ocean acidification

Overfishing 

Habitat destruction 

Contamination

Coastal erosionOverfishing of herbivore fish

Destructive fisheries 

Chemical contamination, agricultural spills

Coral predators

Synchronized reproduction

M t i l f Coastal protection

Local and antrophicpressures

Tourism 

2 acidification

BiodiversityCoastal development

Medical  and biochemical research

CO2 uptakeCommercial extraction 

Reef area

Changes in structure,

Settlement of epibionts and algae

Base of the food chain

Threats to other ecosystems and populations

Material for construction

Bioactive compounds

Community organizations of 

people

Coastal protection

Examples of disappeared species in some tropical reefs:

Ophiuroids Ricordea florida

Importance of the EFFECTS of the DEGRADATION

Employment

Changes in structure, composition, and abundance of 

the communities 

Direct effectsReduction of reef area

Since 1950 tropical reefs have lost more than 19% of its area.

Changes in structure, composition, and abundance of the communities of coral reef

Reef ecosystems will be replaced by ecosystems with less

Loss of biodiversity

33% of coral reef species are endangered.¼ of the marine species depend on coral reef, so if reefs disappear, they will be also 

Sea snakes Crinoids

Fisheries

Decrease of abundance and diversity ofcommercial species of coral reef fishes.

*12‐14% of world fisheries are linked to coral reefs.

Loss of tourism recreation and

Reef ecosystems will be replaced by ecosystems with less biodiversity  and less productivity. Reefs that remain will be 

stronger but less attractive. 

affected.

Damage or destruction ofcoral colonies causes

epibiont and algaesettlement

More lose of reef area

Indirect effects:

Alteration of the 

Effects on population (goods and services affected)

Reefs are a source of income, food and coastalprotection for over 500 million peopleworldwide and more than 100 million peopledepend economically on these.

ConclusionsCurrently we have enough data to assume that there is a real effect both onglobal level and ecosystem level (ex. goods and services). To make decisionsabout how to handle this matter properly, we should do a better monitoringof the situation to obtain good data.

Twomajor problems for face the recuperation:HungerMore overfishing

Coral reef have resisted increases intemperature and pH increases

Corals are resilient and canrecover even slowly but now

Loss of bioactive compounds

Many species are used inmedicaland biochemical research.It won't be possible to discover newpossible compounds.

Loss of tourism, recreation and associations of people

Economic losses (hotels, divingcenters, commerce, jewelry). Lossof people associations that offergoods and services to tourists andimproved the wellbeing of thecommunity.

Problem: This activities also causedegradation of coral reef.

Reduction of coastal protection

Against tsunamis, erosive processes, tidal waves, etc.

If the CO2 emissions continue this way, it is expected that by the end of the century:

carbon balance

Degraded reef  

Less sink of CO2

Climate change could increase

Bibliography: [1]: Cole, S. (2006). NASA Coral Reef Images Key to New Global Survey. Goddard Space Flight Center. NASA. [2]:Wilkinson, C. (2008). Status of Coral Reefs of the World: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Centre, Townsville, Australia. [3]:  Palumni, S., Richmond, R., Hughes, T. (2012). Consensus Statement on Climate Change and Coral Reefs. 12th International Coral Reef Symposium. 

Previsions for the future

Malaria

Anticancerigens

HIV

Bactericidals

*Coral reef are capable ofabsorbing more CO2 thanrainforests

temperature and pH increasesseparately, but not both factorstogether.

recover even slowly, but now,the damages are occurring toofast.

Surface temperatures of the ocean: ↑2‐3ºCSea level: ↑1,7m

↓pH of the oceans: 8,1  7,9 Frequency of tropical storms will increase 

More degradation and by 2050 all reef endangered