ASSESSING THE IMPACT OF CLIMATE CHANGE ON MARINE BIODIVERSITY: A STUDY OF CORAL REEF ECOSYSTEMS

Abstract

Human activities through fossil fuel combustion combined with deforestation and modified land management practices have induced substantial alterations in atmospheric greenhouse gas contents especially carbon dioxide and methane emissions. These alterations triggered by heat stress together with ocean acidification and falling carbonate ion levels caused both global warming and ocean acidification thus becoming major threats to coral reef ecosystems. Observational evidence shows that increasing coral bleaching events and reduced calcification rates together with numerous subtle but essential ecological and physiological changes affect coral reefs. Scientists make a prediction of coral reef ecosystems becoming rare worldwide during this century because reef-building corals and other species show no signs of adapting to these environmental changes. Many experts believe that preventing dire outcomes for coral reefs will be possible through proper control of atmospheric carbon dioxide rise along with local pressure reduction including overfishing and declining water quality. Coral reefs maintain vital importance for the survival of millions of people which requires immediate adoption of protective measures. It has been concluded that the current ocean acidification rate together with temperature increase patterns threaten coral reef ecosystems to a significant degree. The ongoing atmospheric CO2 concentration trends will enable coral reefs to exceed their critical carbonate ion requirements while surpassing their temperature tolerance thresholds within short periods. The situation is predicted to become more severe for tropical and subtropical coastal areas due to expected increases in storm strength and rainfall intensity and sea-level rise. Under these circumstances coral reefs will experience dramatic shrinkage in their size distribution along with corals becoming extremely rare reef-dwelling animals within tropical and subtropical regions. Multiple species that depend on reef-building corals and carbonate structure creation will face extinction due to these circumstances. Research does not show sufficient signs of coral-dinoflagellate symbiosis to match the swift modifications in human-generated environmental changes.