Menu
Allianz and Afloat - Supporting Irish Boating

Ireland's sailing, boating & maritime magazine

Marine Institute Banner Advert

Microplastics in Rivers Trapped in Sediment & Stay in Headwaters, New Research Finds

15th January 2022
The new research published this week notes that swirling river waters can trap lightweight microplastics that otherwise might be expected to float – depositing them in riverbeds

Lightweight microplastics can be trapped in freshwater sediment and stay longest at “headwaters” or sources of rivers and streams, a new study has found.

It can then take up to seven years for such pollutants to travel just a kilometre further towards the sea or ocean, a study by researchers at the University of Birmingham, Northwestern University and Loyola University Chicago in North America calculates.

The research published in the journal Science Advances follows a similar study released last autumn by the University of Leicester.

As reported by Afloat, the University of Leicester research found microplastics may travel at less than 0.01km per hour.

The new research published this week notes that swirling river waters can trap lightweight microplastics that otherwise might be expected to float – depositing them in riverbeds.

“As rivers are in near-constant motion, researchers had previously assumed that lightweight microplastics were swept rather swiftly towards the ocean and rarely interacted with riverbed sediments,” the authors state.

They set out a new model describing processes that influence particles, including hyporheic exchange, involving widely abundant microplastics which are 100 micrometres in size and smaller.

The scientists used global data on urban wastewater discharges and river flow condition to discover that microplastic pollution resides the longest at the source of a river or stream - known as the ‘headwaters’ that are furthest away from the ocean.

In headwaters, microplastic particles move at an average rate of five hours per kilometre, but can then take up to seven years to move one kilometre under low-flow conditions.

Stefan Krause, professor of ecohydrology and biogeochemistry at the University of Birmingham, noted that the slow movement of microplastics downstream” makes it more likely that aquatic species ingest microplastics and propagate them through the food-web.

This can "potentially cause harm for environmental and public health”, Krause said.

“Our findings highlight that we need to develop strategies to reduce future microplastic inputs into rivers, and find effective solutions to remove the existing legacy of plastics from our rivers in order to restore freshwater ecosystems,” he said.

The study was led by Dr Jennifer Drummond at the University of Birmingham, and supported by a Royal Society Newton International Fellowship, Marie Curie Individual Fellowship, the German Research Foundation, the Leverhulme Trust and the National Science Foundation.

The paper ‘Microplastic accumulation in riverbed sediment via hyporheic exchange from headwaters to mainstems’ by Jennifer D. Drummond, Uwe Schneidewind, Angang Li, Timothy J. Hoellein, Stefan Krause and Aaron I Packman is published in Science Advances.

Published in Marine Science
Lorna Siggins

About The Author

Lorna Siggins

Email The Author

Lorna Siggins is a print and radio reporter, and a former Irish Times western correspondent. She is the author of Everest Callling (1994) on the first Irish Everest expedition; Mayday! Mayday! (2004) on Irish helicopter search and rescue; and Once Upon a Time in the West: the Corrib gas controversy (2010).

We've got a favour to ask

More people are reading Afloat.ie than ever thanks to the power of the internet but we're in stormy seas because advertising revenues across the media are falling fast. Unlike many news sites, we haven’t put up a paywall because we want to keep our marine journalism open.

Afloat.ie is Ireland's only full–time marine journalism team and it takes time, money and hard work to produce our content.

So you can see why we need to ask for your help.

If everyone chipped in, we can enhance our coverage and our future would be more secure. You can help us through a small donation. Thank you.

Direct Donation to Afloat button

Marine Science Perhaps it is the work of the Irish research vessel RV Celtic Explorer out in the Atlantic Ocean that best highlights the essential nature of marine research, development and sustainable management, through which Ireland is developing a strong and well-deserved reputation as an emerging centre of excellence. From Wavebob Ocean energy technology to aquaculture to weather buoys and oil exploration these pages document the work of Irish marine science and how Irish scientists have secured prominent roles in many European and international marine science bodies.

 

At A Glance – Ocean Facts

  • 71% of the earth’s surface is covered by the ocean
  • The ocean is responsible for the water cycle, which affects our weather
  • The ocean absorbs 30% of the carbon dioxide added to the atmosphere by human activity
  • The real map of Ireland has a seabed territory ten times the size of its land area
  • The ocean is the support system of our planet.
  • Over half of the oxygen we breathe was produced in the ocean
  • The global market for seaweed is valued at approximately €5.4 billion
  • · Coral reefs are among the oldest ecosystems in the world — at 230 million years
  • 1.9 million people live within 5km of the coast in Ireland
  • Ocean waters hold nearly 20 million tons of gold. If we could mine all of the gold from the ocean, we would have enough to give every person on earth 9lbs of the precious metal!
  • Aquaculture is the fastest growing food sector in the world – Ireland is ranked 7th largest aquaculture producer in the EU
  • The Atlantic Ocean is the second largest ocean in the world, covering 20% of the earth’s surface. Out of all the oceans, the Atlantic Ocean is the saltiest
  • The Pacific Ocean is the largest ocean in the world. It’s bigger than all the continents put together
  • Ireland is surrounded by some of the most productive fishing grounds in Europe, with Irish commercial fish landings worth around €200 million annually
  • 97% of the earth’s water is in the ocean
  • The ocean provides the greatest amount of the world’s protein consumed by humans
  • Plastic affects 700 species in the oceans from plankton to whales.
  • Only 10% of the oceans have been explored.
  • 8 million tonnes of plastic enter the ocean each year, equal to dumping a garbage truck of plastic into the ocean every minute.
  • 12 humans have walked on the moon but only 3 humans have been to the deepest part of the ocean.

(Ref: Marine Institute)

Featured Sailing School

INSS sidebutton

Featured Clubs

dbsc mainbutton
Howth Yacht Club
Kinsale Yacht Club
National Yacht Club
Royal Cork Yacht Club
Royal Irish Yacht club
Royal Saint George Yacht Club

Featured Brokers

leinster sidebutton

Featured Associations

ICRA
isora sidebutton

Featured Webcams

Featured Events 2022

Featured Sailmakers

northsails sidebutton
uksails sidebutton
quantum sidebutton
watson sidebutton

Featured Chandleries

CHMarine Afloat logo
osm sidebutton
https://afloat.ie/resources/marine-industry-news/viking-marine

Featured Marinas

dlmarina sidebutton

Featured Blogs

W M Nixon - Sailing on Saturday
podcast sidebutton
mansfield sidebutton
BSB sidebutton
wavelengths sidebutton
 

Please show your support for Afloat by donating