Though ocean dead zones often occur naturally, they can also be triggered by human activity.
These zones are identified by the reduced levels of oxygen in the water, commonly referred to as hypoxia.
There are many factors that combine to create dead zones, but nutrient pollution is the primary cause of those zones created by humans.
Excess nutrients that run off land or are piped as wastewater into rivers and coasts can stimulate an overgrowth of algae, which then sinks and decomposes in the water. The decomposition process consumes oxygen and depletes the supply available to healthy marine life.
Fifty years ago there were only 49 identified ocean dead zones. That number has increased to a frightening 405 dead zones worldwide.
Nestled between Sweden, Finland, and Poland in the Baltic Sea lie seven of the largest of the ocean dead zones. This particular sea is especially vulnerable to changes in the environment because it has a mix of both salt and fresh water marine life. The Baltic Sea also triggers changes to the climate in these areas, which in turn has an impact on the oceanic eco-system.
The second largest dead zone is in the Gulf of Mexico where oil drilling and spills happen at a increasing rate.
According to the Scientific American, approximately 83,000 tons (75,000 metric tons) of fish and other ocean life are lost to the Chesapeake Bay dead zone off the coast of Delaware each year. The fishing industry has already suffered and at this rate will continue to suffer severely.
For communities relying on seafood as a major food source, the future for harvesting locally looks unlikely.
It is very important that we take action now. The dead zone in the Black Sea recovered following the collapse of the Soviet Union. The reduction in fertilizer runoff from fields in both the Ukraine and Russia was enough to reverse the damage.
By reducing our use of fossil fuels, and using good farming practices that keep the environment safe there is a chance we can help save our oceans.
Image: Public Domain
If you read this far, we assume you found this post interesting. Please help Blackle Mag thrive by sharing it using the social media buttons below.Tweet
What did you think of this post? Let us know in the comments below.