Chinese Algae And The Pollution Connection

by: Randy Travis

Green algae covering more square miles than the state of Massachusetts has appeared off the coast of China for the sixth year in a row. Several hundred tons of this Chinese algae that threatened the Olympics in 2008 is growing in the waters near beaches north of Shanghai and washing ashore faster than it can be collected. Instead of burying themselves in sand, beach goers are burying themselves in Chinese algae nearly sixteen inches deep in many places.


(photo ZME Science)

An Environmental Mess On A Huge Scale

This year’s bloom is the largest of the last six years and bulldozers are being used to clean the areas for tourists and locals who would rather swim in the water than on or through a green carpet. Local officials want to remove as much as they can from the beaches because the algae can emit toxic gases when it decays. Cleanups begin as early as 3 am and continue throughout the day. Scientists and researchers have determined that the Chinese algae is not immediately harmful to humans, so there’s no danger swimming in the waters or playing with the algae on the beaches. Aside from some possible mild skin irritations, beach goers are not at risk.

The existence of the algae means that a drastic change has occurred in the ecosystem that may be dangerous or harmful in the long run. There are many reasons why the algae blooms could be happening in such vast quantities and none of them are necessarily good. Algae requires food and specific conditions to thrive and our sewage, agricultural or industrial waste and pollution provide the green biomass with all that it needs.

What to do when you are cold at the beach in China?

(AP Photo-Ng Han Guan)

Such a large bloom so close to a populated area could indicate that too much raw sewage is being dumped into the oceans, or industrial plants are releasing chemicals they shouldn’t be or in larger quantities than they should. These things increase nutrients, nitrogen and phosphate levels in the ocean, offering food for algae to thrive on.

(photo ZME Science)

(photo ZME Science)

Where Did The Algae Come From?

Algae is a great indicator of pollution since the two generally go hand in hand. It’s sudden appearance invariably points to increases in pollution. Fluctuations in acidity of the ocean waters from pollution or acid rains can cause certain kinds of algae to thrive. Organic matter such as sewage or fertilizers that are washed from farms and heavily populated areas also provide nutrients necessary to sustain algae. Warm waters and sunny days offer the other necessary elements and then we see massive blooms. Some algae thrive in waters with heavy metals which would indicate pollution from yet another source. Oil pollution will also feed several other kinds of algae and the presence of those types would indicate a possible oil spill, leak, or illegal dumping. The fact that large algae blooms typically occur close to industrial areas, waste water treatment plants, and populated areas only further enforces the fact that our pollution is causing this to happen.

Is CO2 Linked To The Algae Bloom?

In addition to pollution, the cause could be changes in the carbon dioxide levels in the oceans, something else that algae needs to survive. Coral reefs help to regulate carbon dioxide in our oceans which, among other things, helps regulate the growth of algae. Coral and algae have a symbiotic relationship in that algae creates oxygen that corals need, and corals create carbon dioxide that the algae needs. As coral reefs are killed or destroyed, the carbon dioxide levels in the oceans increase. This increase in carbon dioxide helps provide better conditions for algae to grow and then we see larger and more widespread blooms. To add insult to injury, these large blooms block out necessary sunlight and nutrients from the coral reefs, effectively smothering them. This creates a cycle of coral death, carbon dioxide increase, and algae growth that is further perpetuated by our irresponsible pollution.

kids swimming in Algae

(photo ZME Science)

Larger Ocean Impacts

And it’s not only the reefs that could be in danger. Such a large mass of algae can be dense enough to remove significant amounts of oxygen from the waters creating conditions that could kill other plants and marine life. These plants and marine life feed both humans and ocean dwelling creatures alike. The pollution we continue to dump into the oceans now could eventually leave us with oceans absent coral reefs, sea grass, and many fish that ocean side communities require to survive.