Page 41 - ALG Issue 2 2017

Unearth the secrets of soil health with ‘Earthworm Watch’
Earthworm Watch invites National Allotment Society members to count earthworms and categorise soils
across Britain to help scientists reveal relationships between earthworms, carbon and soil health.
Gardeners and allotment owners appreciate the immense value that earthworms play, more than most for healthy soils, wildlife and for growing. In an average garden there can be as many as eight different species and a spadeful of healthy soil should contain tens of earthworms. Naturalist Charles Darwin understood the role of earthworms in agricultural soils, with his experiments for over 30 years observing their behaviour to determine their senses, movement and the rate by which they recycle soils. This led to his nal book ‘The Formation of Vegetable Mould through the Action of Worms, with Observations on their Habits’ selling more copies than his ‘Origin of Species’.
However, historically there hasn’t been accurate knowledge around the abundance of earthworms in UK soils compared with other invertebrate groups. Scientists at Earthwatch (Europe) and The Natural History Museum are, therefore, asking the public
to sign up to Earthworm Watch, a national citizen science project to understand earthworm abundance and quantify their role in soil productivity, carbon storage and ooding. The project, in partnership with Earthwatch (Europe), The Natural History Museum and Earthworm Society of Britain, has been created speci cally to study earthworms in urban green spaces.
Why should you take part?
Earthworms are ‘ecosystem engineers’ whose activities literally change the structure of the soil. Some earthworms live and feed on decomposing leaf litter on the surface. Soil feeding and deep-living earthworms make horizontal and vertical burrows with soil feeders, ingesting soil directly for burrows and for food. Deep living earthworms drag leaves from the
surface down into their burrows at night. The burrowing actions allow spaces for
air, water and the roots of growing plants. The recycling of soils and organic material passing through earthworm bodies means nutrients are returned to the soil in a form that plants can take in. Without earthworms (along with bacteria and fungi) to break down, aerate and take carbon in fragments into the soil, other life would quickly suffer.
There are 31 species of Earthworms in the UK, but without a baseline, we just don’t know how many of these are present in the soil. As Victoria Burton, PhD student and Lead Researcher on the project explains: “I’ve travelled all over the UK discovering how many and what types of earthworms are in farmland and woodland soils; but what about urban areas, gardens, and allotments’?’ We also don’t fully understand the impacts of different fertilisers, pesticides and composting approaches on earthworm numbers. With your help, scientists can hopefully provide answers to some of these important questions.
How can you take part?
The survey itself takes around an hour to complete and simply requires you to dig two shallow pits in two different habitats in your allotment or green space. These could be a lawn or a vegetable bed; then we ask you to count the earthworms and categorise
the type and carbon content of the soil there. Part of the survey requires you to do a mustard test, which isn’t harmful to the earthworms, but encourages them to the surface.
Alan notes that “there have been many reasons why people have engaged with
the survey so far. One of the greatest motivations has been a desire to improve the state of nature and contribute to science. Many other people see Earthworm Watch
as a fantastic opportunity for their families, school classes, or community groups, to
learn about earthworms’.
Since our launch, the Earthworm Watch
team has engaged over 2500 community groups, with over 750 people signed up. So far, we have recorded over 250 data points from Jersey in the English Channel to Elgin in Scotland with a target of 500 to be completed by the end of the 2017 season.
Visit our website to nd out more: www. earthwormwatch.org
The
Earthworm
Watch
Experiment
Our latest Earthworm Watch Experiment is a new opportunity
for you to deepen your experience
of Earthworm Watch and help our scientists learn more about the best habitats for earthworms. Following
on from completing the Earthworm Watch survey, the experiment asks you to manipulate one square of habitat by adding a form of compost or organic material. After a month you will be able to re-survey, to see how it compares with the regular square (left unchanged!).
Find out more by reading our recent blog at www.earthwormwatch.org/ blogs/composting-and-earthworm- watch-experiment and register at www.earthwormwatch.org/science- experiment.
http://eu.earthwatch.org/ http://www.nhm.ac.uk/ http://www.earthwormsoc.org.uk/
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