News Release

Climate-change set-back for acidified rivers

Peer-Reviewed Publication

Cardiff University

Climate change is hampering the long-term recovery of rivers from the effects of acid rain, as wet weather counteracts improvements, according to a new study by Cardiff University.

The research, by Professor Steve Ormerod and Dr Isabelle Durance of the School of Biosciences, took place over a 25 year period around Llyn Brianne in mid-Wales. Their findings are published online today in the British Ecological Society's Journal of Applied Ecology.

Carried out in 14 streams, the research involved assessing the number and variety of stream insects present each year. The scientists measured concentrations of acid and other aspects of stream chemistry, and documented climatic variation such as warmer, wetter winters.

With average acidity in rivers falling due to improvements in the levels of acid rain, the researchers expected that up to 29 insect species to have re-colonised the less acidic Welsh streams. These included sensitive mayflies and other groups often eaten by trout and salmon.

The findings however, showed a large short-fall in biological recovery, with just four new insect species added to the recovering rivers sampled.

Professor Steve Ormerod, who has led the project since it began in the early 1980s, said "Since the 1970s, there have been huge efforts to clean-up sources of acid rain, and our research shows that rivers are heading in the right direction. However, our results support the theory that acid conditions during rainstorms kill sensitive animals. During recent wetter winters, upland streams have been acidified enough to cancel out up to 40 percent of the last 25 years' improvements: climatic effects have clearly worked against our best efforts."

Dr Isabelle Durance, who co-authored the paper said: "More and more evidence now shows that some of the worst effects of climate-change on natural habitats come from interactions with existing stressors - in this case acid rain. A wider suggestion from our research is that by reducing these other environmental problems, we can minimise at least some climate-change impacts."

###

Notes to editors

1. S J Ormerod and Isabelle Durance (2008). Restoration and recovery from acidification in upland Welsh streams over 25 years. Journal of Applied Ecology, doi: 10.1111/j.1365-2664.2008.01587.x, is published online on 3 December 2008.

2. The Cardiff School of Biosciences addresses the major biological questions which face health and life scientists. The major research areas of the School are: biodiversity and ecology, connective tissue biology, environmental biochemistry and microbiology, mammalian genetics, molecular enzymology and entomology, and neuroscience cell biology. The School also houses the Common Cold Centre, the world's only centre dedicated to researching and testing new medicines for treatment of the symptoms of flu and the common cold.

The School achieved a one hundred per cent success in the national, independent assessment of university teaching quality. The top 'excellent' grade was awarded to Pure and Applied Biology, Biochemistry, Anatomy and Physiology, and to the first and second year pre-clinical training for doctors and dentists.

3. Cardiff University is recognised in independent government assessments as one of Britain's leading teaching and research universities.

2008 marks the 125th anniversary of Cardiff University having been founded by Royal Charter in 1883.

Today the University combines impressive modern facilities and a dynamic approach to teaching and research. The University's breadth of expertise in research and research-led teaching encompasses: the humanities; the natural, physical, health, life and social sciences; engineering and technology; preparation for a wide range of professions; and a longstanding commitment to lifelong learning.

Cardiff is a member of the Russell Group of the UK's leading research universities.

Visit the University website at: www.cardiff.ac.uk

4. The British Ecological Society is a learned society, a registered charity and a company limited by guarantee. Established in 1913 by academics to promote and foster the study of ecology in its widest sense, the Society has 4,000 members in the UK and abroad. Further information is available at www.britishecologicalsociety.org.

5. Copies of the paper and photographs are available from Becky Allen, British Ecological Society Press Officer, tel: +44 (0)1223 570016, mob: + 44 (0)7949 804317, email: beckyallen@ntlworld.com.

6. For further information:
Professor Steve Ormerod
School of Biosciences
Cardiff University
Tel: 029 20 875871
Email: ormerod@cardiff.ac.uk


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.