Takaaki Kasuga of Osaka University led the group, which created a circuit board comprised mostly of cellulose nanofibers that alert farmers to low soil humidity. The sensor biodegrades in a little over a month.
Technical challenges remain, however. The sensors contain small amounts of metals that don’t break down in the environment, and the sensors need an external power source. Kasuga tells NHK Japan he hopes to solve these issues before the sensors are available for commercial sale.