7 wonders of the soil
The humble dung beetle relies almost exclusively on faeces, playing a crucial role in keeping the soil fertile and lowering levels of the greenhouse gas nitrous oxide. There are around 10,000 species of dung beetle, everywhere in the world except Antarctica, and ranging from 0.2 to 17 centimetres long. There are three types: rollers make balls of faeces, sometimes 50 times their own size, and roll them into burrows; tunnellers dig below the dung; while dwellers live and breed within it. In the process they fertilize and improve the soil: rollers and tunnellers drag and bury dung up to 60 centimetres underground, distributing nutrients, aerating soil and helping water to percolate through. This also sequesters carbon and reduces the nitrous oxide – a greenhouse gas over 300 times more powerful than carbon dioxide – emitted by manure. New Zealand plans to import and release 11 species of foreign dung beetle in order to manage livestock waste and reduce greenhouse gases.