<
https://www.scientificamerican.com/article/microplastic-pollution-is-messing-with-photosynthesis-in-plants/>
"Microplastics are now a ubiquitous part of our daily physical reality. These
minuscule fragments of degrading plastic now suffuse our air, our soil, the
food we eat and the water we drink. They’re being detected everywhere
researchers look, from Antarctic sea ice to human brains.
As scientists develop a better idea of where microplastics are accumulating in
the environment, they’re just beginning to understand how these pollutants
affect one of the most essential and widespread kingdoms of life on Earth:
plants. A new study, published on Monday in the
Proceedings of the National
Academy of Sciences USA, reveals how microplastics hinder photosynthesis
across a wide range of plant species—including crucial food crops. “It’s really
scary,” says Marcus Eriksen, a marine scientist at the 5 Gyres Institute, a
nonprofit plastic pollution research organization, who was not involved in the
study.
The researchers found that the presence of microplastics (plastic particles
that are less than five millimeters in size) can reduce photosynthesis by as
much as 7 to 12 percent, on average. That could range from 6 to 18 percent in
terrestrial crops, 2 to 12 percent in marine plants such as seaweed and 4 to 14
percent in freshwater algae. “The exposure to microplastics was not surprising
at all,” Eriksen says. “What surprised me was the level of impact.”
A generalized reduction in photosynthesis at such a scale could have major
implications for the global food supply, according to the study’s researchers.
With the current rates of worldwide plastic production (and resulting
microplastics exposure), farmers could see a 4 to 13.5 percent yield loss per
year in staple crops such as corn, rice and wheat over the next 25 years.
Additionally, seafood production could drop by up to 7 percent as aquatic
ecosystems lose the algae that forms the base of their food webs. This would
seriously impact the global economy and exacerbate food insecurity for hundreds
of millions of people, according to the study’s authors.
Decreased photosynthesis could also hamper efforts to fight climate change. As
plants photosynthesize, they draw carbon dioxide from the air into their
tissues and store it in the form of sugars. Most climate models assume plants
will be able to take up atmospheric carbon at a consistent rate over the next
several decades. But if less carbon is sequestered in forests, grasslands and
kelp beds than researchers had predicted, that will make mitigating warming
that much harder."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
