Rise of Arabian Sea Plankton May Threaten Fisheries as Dead Zones Grow

First Posted: Sep 10, 2014 06:33 AM EDT
Close

A growing dead zone may just threaten fisheries in Arabia. Scientists have found that the rapid rise of an unusual type of plankton in the Arabian Sea could be disastrous for nearby fish.

The plankton in question is called Noctiluca scintillans. This unusual dinoflagellate eats other plankton and also draws energy from the sun with the help of microscopic algae living within its cells. The plankton is green in color and colors the Arabian Sea in an emerald swath each winter. Yet it seems like the bloom of plankton is growing.

"These blooms are massive, appear year after year, and could be evastating to the Arabian Sea ecosystem over the long-term," said Helga do Rosario Gomes, one of the researchers, in a news release.

The main issue is that Noctiluca has a varied diet, which means that it has an edge over other organisms. In fact, the green algae in its cells allow it to exploit oxygen-starved dead zones. It can also swim down in the water column to find nutrients, swim upward to find light and even eat other small organisms.

In order to better understand Noctiluca, the researchers studied the organism over three successive winters. They sampled and performed experiments on the organism. They found that Noctiluca grew faster in the light than in the dark, and that its carbon-fixation rate rose up to 300 percent when placed in oxygen-starved water.

They also found the main issue behind the blooms. Massive sewage flows into the Arabian Sea as the coastal population continues to grow. Mumbai's population has doubled to 21 million in just the last decade, and the region now sends 63 tons of nitrogen and 11 tons of phosphorus into the sea each day. This, in turn, fuels the growth of the organisms.

The problem is that Noctiluca could help contribute to the degradation of fisheries if blooms continue to expand. By creating dead zones where little oxygen exists, fish are pushed elsewhere and can impact the economy.

The findings are published in the journal Nature Communications.

See Now: NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone

©2017 ScienceWorldReport.com All rights reserved. Do not reproduce without permission. The window to the world of science news.

Join the Conversation

Real Time Analytics