I made a miniature version of the Singing Compost for an unusual occasion: the British Soil Science Society’s annual conference. Held in the cricket stadium buildings, the conference brought to Cardiff an international crew of soil scientists and stakeholders. Together with Anna Colin from the Centre for Art and Ecology Goldsmiths, we explained the project to interested attendees, and went to a few talks. Artists Daro Montag, Jo Pearl and Phil Lambert also showed work in the conference’s culture room.

 

 

I attended an interesting talk from Bob Klein Lankhorst of Royal Ejkelkamp, a Dutch Company specialising in soil monitoring and analysis. They are developing a tool for fast identification and counting of soil mineral and animal content, pushing a liquid soil mix through a millimeter wide window. A microscope with a video output feeds into an AI system that lists the various items passing through the window. This didn’t provide microbial scale information, but the visuals and data were nevertheless very engaging.

 

Many thanks to prof Jack Hannam for the invitation!

 

Tech note:

We found out later that the copper and zinc electrodes we used generate a current due to their electro-chemical properties (the oxidation of zinc occurs at the anode, while the reduction of copper ions happens at the cathode). It is possible that electrogenic bacterial populations close to the electrodes contribute to the electrical output, but most electricity harvested is from the copper-zinc oxydo-reduction reaction, with moist soil acting as the electrolyte. This system is referred to as an Earth Battery.