Answer:
Increase nutrient concentration
Step-by-step explanation:
Flood water runoff can take with it material from areas occupied by industries and crops. These areas have a large amount of chemical and organic waste arising from the result of agricultural and industrial activities. In this way, when the floodwaters carry this type of wastewater and flow into an aquatic environment with the presence of coral reefs, it causes an increase of nutrient concentration in that environment. This causes negatively affects the aquatic environment, causes eutrophication and harms coral reefs.