Core of the sensor: The individual fields (light blue) contain several substrates for different enzymes in addition to control substances.
(Photograph: Kilian J. Kessler)
Nonetheless, processes in the soil are highly complex and it is still difficult to derive direct recommendations for agriculture from the measurements. “We first have to examine more closely how enzyme activity, which we can now measure rapidly and in a standardised way, relates to soil quality,” Meller says, “and to do that, we need a huge amount of data.” Their data collection efforts will soon get a boost from their first customers: several researchers, including some at the Research Institute of Organic Agriculture (FiBL), will begin testing the first version of the Digit Soil sensor this year. This data will then help Meller and Iven to validate their measurement methods and link the findings with processes in the soil.
Ultimately, the two scientists aim to use their rapid test to map how different actions affect the soil. They eventually want to offer the authorities a tool that will aid in providing sustainable support for soil health. In the future, farmers should be able to use the sensor themselves to monitor the quality of their land and the effects of their actions – such as what fertilisers and pesticides they should spray on their fields and which ones they would do better to avoid.
Meller and Iven secured an ETH Pioneer Fellowship for their idea in 2020. At the moment, they are working to make the sensor even more compact. They also hope to have it transmit data wirelessly to a computer or smartphone by the end of 2021.
