Priority chemicals and marine biodiversity - Mission Blue

February 1, 2015

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From our new partners at the GOES Foundation (Global Oceanic Environmental Survey):

by Dr. Howard Dryden, GOES Founder

Nature 2010 and Nature 2011 reported that there has been a 40% drop in primary productivity in the North Atlantic since the 1950s. At the same time, oceanic pH started to decline sharply, causing seawater to acidify.  This trend may be related to an increase in industrial output and carbon dioxide emissions. However, as a marine biologist specializing in some of the largest aquarium life support systems in the world, I know that carbon dioxide is used to increase primary productivity. Woods Hole reported that an increase in carbon dioxide increased photosynthetic productivity, yet over the last 60 years there may have been a reduction by 40%. A slight increase in temperature would also be expected to increase productivity.

According to the IPCC report 2014, human-caused carbon dioxide emissions only account for 3% of all the emissions entering the atmosphere. The oceans are responsible for between 50% and 80% of all atmospheric carbon dioxide fixation, buffering the atmosphere from more rapid changes. If we have truly lost 40% of this CO2 fixation capacity, the reduction in primary productivity could account for the increase in atmospheric carbon dioxide and ocean acidification.

Increased atmospheric carbon dioxide and ocean temperatures should increase primary productivity, but given that there has been a reduction, could there be another reason for these drops in pH, primary productivity and climate change?

From MARBEF we know that priority chemicals such as PCBs (polychlorinated biphenyls) are found at concentrations over 1 ug/l in the Southern Oceans. We also know that concentrations over 1 ug/l will impact protists (including plankton) by reducing photosynthetic activity. When we factor in all of the other priority chemicals such as PBDE (flame retardants) and methylmercury, it becomes apparent that priority chemicals may be responsible for this reduction in primary productivity and indirectly responsible for the increase in atmospheric carbon dioxide and ocean acidification.

Studies suggest that atmospheric carbon dioxide will continue to increase for the next 50 years. If the current hypothesis is correct that carbon dioxide dissolution into the oceans accounts for ocean acidification, then acidification will continue and the pH will fall below 7.9. At this level of acidity, plankton such as carbonate-based coccolithophores and the eggs of many species of fish and crustacea cannot survive. Without fish and crustacea we lose the whales, seals, penguins and polar bears that rely on them for food, and without coccolithophores we lose around 50% of the capacity of the oceans to sequester carbon dioxide and buffer the planet.

At the current rate of change, pH 7.9 will be reached in 25 to 40 years. If we accept the current hypothesis concerning climate change, then it is inevitable that there will be a huge shift in marine biodiversity and reduction in carbon sequestration that will accelerate climate change, putting the entire marine ecosystem at risk. If we lose the marine ecosystem then the terrestrial system will follow.

However, if preventing priority chemicals could play such a significant role in mitigating ocean acidification alongside reducing CO2 emission from fossil fuels, there is a chance that we can reverse the trend. Slowing ocean acidification could allow marine ecosystems to recover in a matter of a few years. Protists would be able to increase the pH and sequester atmospheric carbon dioxide, but this all must happen before ocean acidity falls below pH 8.0.

The GOES Foundation is about debating these issues and raising awareness regarding the delicate nature of the marine ecosystem and the inevitability of a cascade failure of the marine ecosystem over the next 25 to 40 years if nothing is done to prevent priority chemicals from entering the environment.

GOES Mission:

  1. Raise awareness of priority chemicals in the marine environment and implications with regards to marine biodiversity
  2. Raise awareness of related public health, water and food security implications
  3. Identify sources of priority chemicals and opportunities for the circular economy to deal with the issues

GOES Research: Global Oceanic Environmental Survey for priority chemicals

  1. Priority chemicals. Four of the most toxic include: PCBs, PBDE, methylmercury, organo-tin
  2. Sample biomass (a measure of all living organic organic matter) data to be used to measure primary productivity
  3. Genotyping, DNA analysis of every living organism in the sample including viruses

The GOES Foundation is based in Edinburgh, Scotland. For more information visit www.goesfoundation.com.

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