How humans activities affect the ocean in a positive and a negative way?

Negatives on the left of the dash, positives on the right

Overfishing-some organisations try to stop this by protecting certain areas of coastline

Polluting- particularly oil spills, organisations put netting around the spill to prevent it spreading

Littering (throwing trash)- people are spreading the Word not to trash litter

Killing Coral Reefs(which messes up the food web in the ocean)- there was a story about this on the news the other day (people who are reading this later, don't worry).

Thus, it turns out that people's actions impact the ocean in a very negative way- even though the ocean is pretty good at getting rid of pollutants such as oil through chemical processes, humans cause more damage to the ocean than most people know about... The only positives that I can think of are just some organisations such as the RSPB, BTO etc. are trying to prevent these negatives that are listed from happening, which is of course good news, but it is only righting what we have already done wrong, not making a good impact to the ocean from the start.