Figure 2: | Scientific Reports

Figure 2

From: Listening to earthworms burrowing and roots growing - acoustic signatures of soil biological activity

Figure 2

AE monitoring during maize roots growing in a soil filled glass cell. Time-lapse images were taken to monitor maize roots growing in the glass cell from the day the geminated seeds are planted (a) to the last day of the experiment (b) where X’s indicate the locations of the acoustic sensors. Cumulative number of acoustic events were monitored for the three separate acoustic sensors. (c) The results for sensors S2 and S3 are given after background noise filtering from sensor S1. Simultaneously, the cumulative water uptake was also monitored (d) as well as the estimated total root length (e) determined with time-lapse images (a,b). The vertical dashed line (ce) denote the time when germinated seeds were planted in the glass cells (two days after the beginning of the experiment).