Final answer:
To prevent erosion to the coastline near coral reefs, people can avoid using harmful chemicals, implement sewage treatment systems, and create buffer zones of plants or sand dunes.
Step-by-step explanation:
In order to help prevent erosion to the coastline near the series of coral reefs, people can take several actions. First, they can avoid using harmful chemicals and pesticides in their gardens or farms that could contaminate the water and harm marine life. Second, implementing effective sewage treatment systems can prevent the discharge of untreated wastewater into the oceans. Third, creating buffer zones of plants or sand dunes can reduce the impact of waves and protect the coastline from erosion.