Lower Oxygen Levels Impacting Ocean Food Chain
I’ve brought up the declining oxygen levels before, but of course, it is still happening. Now, researchers have found that only tiny differences of less then 1% have tremendous affects upon marine life:
A new study published in Science Advances finds just the slightest change in oxygen level could have tremendous ramifications on the food chain. Rising temperatures are causing mid-water regions with very low oxygen, known as Oxygen Minimum Zones (OMZs), to expand in the eastern tropical North Pacific Ocean. While some organisms in certain regions may be able to adapt, researchers found those living in OMZs likely cannot as they’re already pushed to their physiological limits.
“These animals have evolved a tremendous ability to extract and use the small amount of oxygen available in their environment,” said study author Brad Seibel, Ph.D., professor of biological oceanography at the University of South Florida College of Marine Science. “Even so, we found that natural reductions in oxygen levels of less than 1% were sufficient to exclude most species or alter their distribution.”
This is a significant research issue of huge importance to the world, demonstrating that the world’s oceans and marine life are at higher risk then previously known. These organisms (zooplankton, krill, crustaceans and fish) are at the very bottom of the world’s food chain. If they collapse – the life in the oceans will collapse.
There have been numerous reports of dying and starving whale pods, beached whales, and dead calves and dead coral all over the world. A whopping 87% of the world’s oceans are dying. Yet despite these reports and evidence, too little is being done to reverse this trend. The trend is clear (even if the oceans aren’t because of pollution) – they’re dying at an accelerated rate. 2 billion people depend on the worlds oceans for food, jobs and daily survival.
Half of the world’s oxygen is produced via phytoplankton photosynthesis. The other half is produced via photosynthesis on land by trees, shrubs, grasses, and other plants. Current rates of ocean acidification and deforestation are decreasing photosynthesis in the ocean and world’s forest.
4.0C/6.4F is the die-off threshold of oceanic phytoplankton which currently regenerates 50% of the planet’s oxygen, and the shut-down threshold of most land plants.