Microscopic plants, using volcanic ash for dating
24 April 2012
This week in the Planet Earth Podcast: we take a closer look at tiny marine plants, which underpin the entire marine food chain and play a vital role in the Earth's climate. Also, how scientists are using volcanic ash called tefra to tell how people may have responded to rapid environmental changes in the recent past.
TV nature programmes have done a brilliant job of showing us the majesty of the world's rainforests. Not only do they harbour a vast diversity of plants and animals, but they also absorb huge amounts of carbon dioxide and so play a role in keeping our climate cool.
But how many people have heard of phytoplankton? Phyto what, I hear you say? Unfortunately, they're not quite as well-known as rainforests, except maybe as Sheldon Plankton in the television cartoon SpongeBob SquarePants.
But it turns out that while phytoplankton represents just two per cent of all plant matter on Earth, it accounts for half of all carbon dioxide absorption from the atmosphere. Richard Hollingham meets plankton expert Katy Owen at the UK's most easterly point, Lowestoft, to find out more.
Click the play button above to listen now.
A full text transcript is available.
Later, Sue Nelson gets up close and personal with volcanic ash from an Italian island called Lipari. Victoria Cullen and Christine Lane from the University of Oxford explain how they're using traces of ash to investigate how our ancestors coped with rapid changes in climate during the last 80,000 years.
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