Dynamics of grassland vegetation in two sheep-grazed agrivoltaic systems in plain and upland areas
Résumé
Agrivoltaic systems emerged to deal with the dual challenges of ensuring renewable energy production
and agricultural production at the same site; however, their ability to deliver grassland ecosystem services
is questioned. During one year, we studied direct effects of various shade conditions induced by solar
panels on abiotic factors (light, soil water and temperature) and vegetation (growth height, greenness:
NDVI, quantity of forage) at one plain and one upland sheep-grazed site. Under exclosure of grazing,
three treatments per site were set up: control (without solar-panel influence), inter-rows (variable
influence) and panel (full influence). The results showed significant modifications of plant microclimate
under solar panels. Soil temperature was cooler in spring and summer, and the soil moisture response
differed at each site. Unexpectedly, vegetation growth under the solar panels was taller in spring and
summer than that in the control, and biomass was larger during summer drought, but the latter declined
during spring of the following year. The results emphasised that, forage quantity and canopy greenness
(NDVI) could be much wider in sheep-grazed agrivoltaic systems than in open grasslands