Unbeknownst to most humans, each day the smallest marine microorganisms in the world battle it out, as revealed in a new study conducted by scientists at the University of Southern California, who say the implications of this process is vital for understanding the ocean's role in climate change.
The team sampled water off the coast of Southern California daily over a five-month time period, taking the samples after an algal bloom. They found that these clouds of microorganisms are not uniform, instead consisting of a constant war between numerous species, with different organisms coming out on top each day.
Phytoplankton, the tiny organisms in our oceans, make up the bottom of their food chain and are important for the removal of carbon dioxide from the atmosphere.
"We witnessed a daily boom and bust among the phytoplankton species," Jed Fuhrman, senior author of a study, said in a press release.
These species perform approximately half of the world's carbon fixation, the process that converts carbon dioxide from the atmosphere into organic compounds, making them of great interest to scientists looking to find ways to curb global warming damages. However, until now, researchers never had a firm grasp on algal blooms, limiting their ability to better understand their role in carbon fixation and sequestration.
Previous efforts to study algal blooms typically relied on microscopes to classify the species of phytoplankton in the mix, whereas the current study instead analyzed the organisms' ribosomal RNA, allowing for more accurate identification and quantification.
"This could shift how this work is done in the future," said David Needham, lead author of the study. "I think a lot of people are going to start taking a closer look at their blooms."
The team found that not only is their an amazing level of phytoplankton diversity within the bloom that they studied, but it was marked by constant shifts in the dominant species. Although some of these changes are likely the result of spatial variability, others were too dramatic for this to be the sole cause, pointing to a constant microbial war within these blooms.
The findings were published in the Feb. 29 issue of Nature Microbiology.
