2.2 Grazing treatments and plant survey
The manipulative experiment was conducted with all 15 plots consisting
of three herd compositions: lamb plots with light, moderate, and heavy
grazing intensities, mixed lamb and dry ewe, dry ewe plots (Fig. 2a, c).
We individually fitted sensors to one lamb and one dry ewe in each lamb
and ewe grazing plot, while both a lamb and a dry ewe were fitted with
sensors in each mixed plot. We monitored the accelerations of 17 sheep,
comprising 11 lambs and 6 dry ewes, for a total of 53,280 tri-axis
accelerations per sheep using accelerometer loggers to collect the
behavioral data of grazers.
To monitor vegetation resources quality and quantity, the above-ground
biomass (AGB), five quadrats of 1 m2 were randomly
placed within each plot on June 20th, August
15th, and September 10th, 2022. In
addition, the aboveground plants were collected and then oven-dried at
105 °C for 15 min and then at 65 °C for 48 h until constant weight. The
nitrogen content in the dried plant samples was measured using the
Kjeldahl method and then multiplied by a conversion factor of 6.25 to
obtain the crude protein content (CP) of the plants (Sanna et al.,
2019).