New research1 by Professor John Downing2 and colleagues3 states that ponds across the globe could bury more carbon than all the world’s oceans.
Professor Downing found that constructed ponds and lakes on farmland in the USA bury carbon at a much higher rate than expected; at a rate 20-50 times the rate at which trees trap carbon4. Ponds take up carbon at a higher rate than larger lakes.
Professor Downing will outline this work to an invited audience on Tuesday 6 May, 1300 at University College London.
Professor Downing says ‘aquatic ecosystems play a disproportionately large role in the global carbon budget. Despite being overlooked in the past, it’s small waterbodies that are important because they take up carbon at a high rate and there are more of them than previously thought. The combined effect is that ponds could be burying more carbon than the world’s oceans, each year.’
Dr Jeremy Biggs, Pond Conservation Director of policy and research, says ‘this research has very exciting implications. It may be that ponds will be the modern equivalent of the swamps that formed coal in the past. But before we all rush into making ponds to trap carbon we need to do some basic research here in the UK. If the rate of carbon uptake in ponds in Europe is the same as that found in the USA study, we may well have discovered an important new natural way of trapping carbon.’
Contact
To arrange interviews please contact Ruth Welters, Pond Conservation Communications Manager ruthwelters@pondconservation.org.uk
Office 01865 483114
Professor Downing will be in the UK from Monday 5 May to Tuesday 6 May.
Notes to Editors
- This research was published on 15 February 2008 in the journal Global Biogeochemical Cycles, 22, ‘Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century’.
- The work was led by Professor John Downing, based at Iowa State University, 253 Bessey Hall Ames, IA 50011-1020 USA. www.public.iastate.edu/~downing and http://limnology.eeob.iastate.edu
- The team that did the work included members from the EU, US and Canada. The work was sponsored by the US National Center for Ecological Analysis and Synthesis and the Iowa Department of Natural Resources.
- Facts and figures
a) Constructed ponds and lakes (impoundments) bury between 148 grams carbon per metre squared per year to a high of 17,000 grams of carbon per metre squared per year (median average of 2000).
b) Impoundments of less than 2 hectares in area bury carbon at a rate of 5000 grams per metre squared per year.
c) Ponds capture carbon in two main ways:
i. algae and plants take carbon dioxide out of the air as they grow and the carbon is captured in the pond when the plants die.
ii. water run-off will bring in carbon from the surrounding farmland soil.
d) Pond size: In the UK, a pond is defined as between one metre squared and two hectares.
e) There are about 400,000 ponds in the UK.
f) There are about 304 million natural lakes and ponds in the world, covering an area of 4.2 million km2 (twice that previously thought); 90% of these waterbodies are one hectare or less in area.
g) The average UK car produces about 1.1 tonnes of carbon each year and the total carbon output from the UK is about 150 mega tonnes of carbon each year.
h) To take up the total carbon output from the UK using trees, we would have to plant trees on an area twice the size of the UK.
