Your data on MRCVSonline
The nature of the services provided by Vision Media means that we might obtain certain information about you.
Please read our Data Protection and Privacy Policy for details.

In addition, (with your consent) some parts of our website may store a 'cookie' in your browser for the purposes of
functionality or performance monitoring.
Click here to manage your settings.

River biodiversity increased by reduced metal pollution
There has been no significant improvement to biodiversity since early 2000s.
Ecological health was improved in the 1990s and early 2000s.

A new study has linked an increase in freshwater biodiversity in the 1990s to a reduction in zinc and copper pollution in England’s rivers.

Researchers say that this is likely due to the decline of coal burning and heavy industry during this time.

The UK Centre for Ecology and Hydrology (UKCEH) uses population counts of invertebrate species to evaluate the ecological health of the river. Through this they are able to assess the river’s biodiversity, as well as considering how pollution might be impacting the river’s ecosystem.

Using Environment Agency data, UKCEH had observed a significant increase in species richness in the 1990s and in the early 2000s. However, they have reported no significant improvement since then.

The UKCEH’s latest study, funded by the Natural Environment Research Council, sought to investigate the reasons behind these changes.

A team of scientists, led by UKCEH, implemented statistical modelling to investigate the chemical and physical factors that might be involved. This included data on temperature, river flow and landscape.

The data consisted of 65,000 individual observations on pollutant measurements and invertebrates from 1,457 sites between 1989 and 2018.

An analysis of the data highlighted how effluent sewage impacted concentrations of ammonia and organic matter, and how this then impacted river wildlife. However, it was the correlation between invertebrate diversity with zinc and copper which was strongest.

Researchers theorise that a reduction in coal burning in the 1980s could be linked to a reduction of metal pollution in England’s rivers. Coal burning is a major source of atmospheric metals pollution, which then ends up in rivers through acid rain.

The decline in heavy industry has also been associated with improved biodiversity in the 1990s. UKCEH says the industry was also responsible for metal pollution, as well as leaking polluted sewage through treated and untreated effluent.

The reduced production of domestic products containing zinc and copper may also have resulted in less metal pollution in the sewage.

Andrew Johnson, an environmental research scientist at UKCEH, said: “There is a widespread desire by the public to improve water quality and biodiversity in our rivers but the problem for policymakers is what steps would be most likely to achieve results.

“Our study provides strong evidence that concentrations of zinc and copper have the biggest influence on invertebrate species richness, so future attempts to increase freshwater biodiversity are unlikely to bear fruit without further reductions in these metals.”

Image © Shutterstock

Become a member or log in to add this story to your CPD history

Free CPD announced for BVNA members

News Story 1
 Zoetis is to present a CPD event for free to members of the British Veterinary Nursing Association (BVNA).

Led by veterinary consultant Ruth Moxon, the one-hour online session is designed to help veterinary nurses discuss parasiticide options with clients. It will advise on structuring recommendations, factors for product choice and moving away from 'selling'.

'How do you recommend parasite treatments to your clients?' will be presented on Tuesday, 20 May at 7.30pm. It is free for BVNA members, with £15.00 tickets for non-members.

Veterinary nurses can email cpd@bvna.co.uk to book their place. 

Click here for more...
News Shorts
DAERA to reduce BVD 'grace period'

DAERA has reminded herd keepers of an upcoming reduction to the 'grace period' to avoid BVD herd restrictions.

From 1 May 2025, herd keepers will have seven days to cull any BVD positive or inconclusive animals to avoid restrictions being applied to their herd.

It follows legislation introduced on 1 February, as DAERA introduces herd movement restrictions through a phased approach. Herd keepers originally had 28 days to cull BVD positive or inconclusive animals.

DAERA says that, providing herd keepers use the seven-day grace period, no herds should be restricted within the first year of these measures.

Additional measures, which will target herds with animals over 30 days old that haven't been tested for BVD, will be introduced from 1 June 2025.

More information is available on the DAERA website.