Population Increases, Bad on Our Oceans
It is currently estimated that three babies are born every second and because we are living longer the population is increasing at an incredible rate. Right now the population growth rate is approximately 1.3% per year. With a little over 7 billion people in the world that is an increase of around 90 million new lives every year. This massive increase each year is causing many problems for the world, one being our ability to manage the garbage and waste that is being used. With the amount of sewage being accumulated many people have turned to dumping it into our oceans because there is too much to be treated. This means not only are the dead zones going to increase in size but new dead zones are going to start appearing if this continues. Another problem we face is the increase in number of fish farms to keeps up with the demand. It sounds good, increasing the growth numbers of fish mean more food for people, but what isn't accounted for is the waste these fish are putting off and the uneaten food pellets. Both of these thing are starting to have a huge impact on the creation of algae blooms and therefore dead zones, and it's possible that if the trend continues this could become a bigger factor than the fertilizer runoff in many places.
Image source: http://www.aratosuav.com/agriculture.html