□ Reasons:- ◇ Global warming as the most significant factor o | Upsc geography
□ Reasons:-
◇ Global warming as the most significant factor of coral bleaching causing large-scale coral death.
◇ El Nino phenomenon has also been related to coral bleaching.
◇ The outbreaks of coral diseases (black band disease, coral plague, aspergillosis and white band disease) cause coral death.
◇ Local factors like increase in siltation of sea waters due to mass flux of sediments and nutrients brought by the steams from the erosion of high islands consequent upon land use changes; pollution of sea waters caused by industrial effluents, urban sewage and oil slicks; destructive fishing practices, overfishing; clearing of marine forests around coral reefs; filling of wetlands (marine forests and wetlands trap sediments and filter pollutants and thus save corals from degradation); mining of coral rocks for building materials; collection of rare coral species etc. are also responsible for coral degradation at local and regional levels.
