Data from: Bioelectrical synchronization of Picea abies during a solar eclipse
Data files
May 26, 2025 version files 15.04 MB
Abstract
Regular light–dark cycles greatly affect organisms, and events like eclipses induce distinctive physiological and behavioural shifts. While well-documented in animals, plant behaviour during eclipses remains largely unexplored. Here, we monitored multiple spruce trees to assess their individual and collective bioelectrical responses to a solar eclipse. Trees anticipated the eclipse, synchronizing their bioelectrical behaviour hours in advance. Older trees displayed greater anticipatory behaviour with early time-asymmetry and entropy increases. These results reveal a relationship between trees, shaped by individual age and physiology as well as collective history. This highlights the significance of synchrony in plants, offering new insights into coordinated behaviours in nature.
https://doi.org/10.5061/dryad.brv15dvhr
We measured bioelectrical potentials using five pairs of differential electrodes from trees in a forest. Each electrode pair was connected to a differential amplifier before data recording. This setup, with electrodes placed on both the inner (xylem) and outer (phloem) layers of the tree, allowed us to capture information about bioelectrical activity throughout the tree’s vascular system. For the collection of xylematic bioelectrical potentials from one tree, ten stainless steel (AISI 316) threaded rods of 6 mm diameter were utilized. These rods were evenly spaced along the trunk, uncovered portions of roots and logs, with a separation distance of 50 cm. Each electrode pair was connected to a differential amplifier prior to recording the data. For the collection of phloematic biolectrical potentials, two recording circles were positioned around the trunk of another tree. One circle was located 1 m above the ground level with a radial distance of 60◦, while the other was located 3 m above the ground level with a radial distance of 90◦. As with the xylematic potential collection, each electrode pair was connected to a differential amplifier prior to analog to digital conversion. The same threaded rods were used to collect biolectrical signals from five logs. The first rod was inserted at the top of each log, and the second was positioned along one of the roots, 50 cm away from the first. Both rods were then connected to the differential amplifier. Signals were transmitted using the double-shielded ultra-low resistance INCA1050HPLC cable from MD Italy, designed for highfidelity audio applications. Recording devices are called Cybertree device, developed by OpenAzienda Srl.
Description of the data and file structure
Data is composed by four datasets, one for plant F connected to the electrodes, and three recordings from the climatic probe that collected real data about temperature, relative humidity, rainfall, solar radiation, cumulative and bioclimatic indexes calculated from measurements. The first file is a .CSV where the rows contain recordings composed in this way: sequential time in seconds, voltage on differential channel 1 in volts, voltage on differential channel 2 in volts, voltage on differential channel 3 in volts, voltage on differential channel 4 in volts, voltage on differential channel 5 in volts, date expressed in month-day-year, time expressed in hours:minutes:seconds. The latter files are .XLS tables containing recordings ranging from 1st Jan 2022 to 14th Nov 2022. Wherever data are not available, empty cells are left. The first row contains column label [measure units], the columns the different readings. Physical sensors readings have a minimum frequency of 1 sample per hour, even though the internal sampling rate is much higher, the output is always the hourly average. "Export_Val_Di_Fiemme_01_01_2022_14_11_2022Indici bioclimatici" has the following column composition: A date (day/month/year hour:minute:second); B average Fregoni index [°C]; C minimum Fregoni index [°C]; D maximum Fregoni index [°C]; E average Huglin index [°C]; F minimum Huglin index [°C]; G maximum Huglin index [°C]; H average Winkler index [°C]; I minimum Winkler index [°C]; J maximum Winkler index [°C]; K normalized average Winkler index [°C]; L normalized minimum Winkler index [°C]; M normalized maximum Winkler index [°C]. "Export_Val_Di_Fiemme_01_01_2022_14_11_2022_Indici cumulati" has the following column composition: A date (day/month/year); B average leaf wetness duration [hours]; C minimum leaf wetness duration [hours]; D maximum leaf wetness duration [hours]; E average evapotranspiration [mm/day]; F minimum evapotranspiration [mm/day]; G maximum evapotranspiration [mm/day]; H average 10°C per day [°C]; I minimum 10°C per day [°C]; J maximum 10°C per day [°C]; K average 18°C per day [°C]; L minimum 18°C per day [°C]; M maximum 18°C per day [°C]; N average 20°C per day [°C]; O minimum 20°C per day [°C]; P maximum 20°C per day [°C]; Q average rainfall [mm]; R minimum rainfall [mm]; S maximum rainfall [mm]; T global solar daily radiation [MJ / (m2 * day)]; U minimum global solar daily radiation [MJ / (m2 * day)]; V maximum global solar daily radiation [MJ / (m2 * day)]. "Export_Val_Di_Fiemme_01_01_2022_14_11_2022_sensori indici orari" has the following column composition: A date (day/month/year hour:minute:second); B average measured temperature [°C]; C minimum measured temperature [°C]; D maximum measured temperature [°C]; E average relative humidity [%]; F minimum relative humidity [%]; G maximum relative humidity [%]; H average leaf wetness [1 = present, 0 = absent]; I minimum leaf wetness [1 = present, 0 = absent]; J maximum leaf wetness [1 = present, 0 = absent]; K average pluviometric rainfall [mm/h]; L minimum pluviometric rainfall [mm/h]; M maximum pluviometric rainfall [mm/h]; N average dewpoint temperature [°C]; O minimum dewpoint temperature [°C]; P maximum dewpoint temperature [°C].
- Chiolerio, Alessandro; Gagliano, Monica; Pilia, Silvio et al. (2025). Bioelectrical synchronization of Picea abies during a solar eclipse. Royal Society Open Science. https://doi.org/10.1098/rsos.241786
