What was one of the primary results of chinese civilization settling in river valleys

Well from what I learned they nearly got wiped out at one point but it was great for agriculture, they grew rice and other plants but they had much flooding

Probably the primary result of Chinese civilizations settling in the river valleys was that they were able to produce more crop produce this way than if they would stay at another place. Doing this, they were able to sustain themselves relatively easily compared to other towns and nations.  

The dangers of an inadequate monetary supply.