Ocean acidification
Anthropogenic forces contribute to coral reef degradation, reducing their resiliency. Some anthropogenic forces that degrade corals include pollution, sedimentation from coastal development, and ocean acidification due to increased fossil fuel emissions. The combustion of fossil fuels results in the emission of green house gases, such as carbon dioxide into the atmosphere. The ocean uptakes some of the emitted carbon dioxide, injurious to the natural processes that occur in the ocean. Ocean acidification results in a lower ocean water pH, negatively affecting the formation of calcium carbonate structures which are imperative to coral development. Developing coastal areas has the potential for chemical and nutrient pollution to run off into surrounding waters. Nutrient pollution causes the overgrowth of water plants which have the ability to out compete corals for space, nutrients, and other resources. Another anthropogenic force that degrades coral reefs is bottom trawling; a fishing practice that scrapes coral reef habitats and other bottom substrate dwelling organisms off the ocean floor. Bottom trawling results in physical wreckage and stress that leads to corals being broken and zooxanthellae expelled.