There is evidence that microplastics can have a negative impact on coral reefs. Microplastics can physically damage coral by abrading their surface and by introducing contaminants that can harm coral tissue. Ingestion of microplastics by coral can also lead to the absorption of toxins, which can cause stress and harm to the coral.
In addition to the direct effects on coral, microplastics can also have indirect impacts by altering the balance of species on a reef. For example, the presence of microplastics in the water can affect the behavior of herbivorous fish, which are important for maintaining the health of coral reefs by controlling the growth of algae.
Overall, the impact of microplastics on coral reefs is an area of active research, and more studies are needed to fully understand the extent of the problem and how it can be addressed. However, it is clear that reducing the amount of plastic that enters the ocean is an important goal in order to protect marine ecosystems, including coral reefs.