Species-Specific Biomass and Essential Oil Traits Across Spatial Positions in an Agrivoltaic System: An Exploratory Field Study of Mediterranean Aromatic Crops

Agrivoltaic systems are regarded as multifunctional land-use strategies, but their effects on high-value aromatic crops remain poorly understood. This exploratory single-site study described biomass production, essential oil yield, antioxidant traits and volatile composition of Thymus vulgaris L., Salvia officinalis L. and Salvia rosmarinus Spenn. at three positions within an agrivoltaic corridor and in an adjacent open-field control. Compared with the open field, the agrivoltaic area received 17.7% less solar radiation, had 6.8% lower reference evapotranspiration and strongly reduced wind speed, and showed 19.2% higher soil water content under the same irrigation schedule. Fresh biomass per plant was 2.4–3.4 times higher at all agrivoltaic positions than in the control, with similar values among positions, while dry matter content varied with position. The most shaded position showed the lowest dry matter content, associated in S. officinalis with a lower proportion of desiccated tissue, and the highest essential oil yield on a dry matter basis (+69.2% in T. vulgaris, +19.4% in S. officinalis and +112.2% in S. rosmarinus), whereas on a fresh weight basis yield was higher only in S. rosmarinus. Estimated oil production per plant was higher under agrivoltaic conditions in all species. Antioxidant capacity was generally highest in the same position, whereas volatile composition differed mainly from open-field control. Although species-specific, the results point to crop position within corridors as a potential agrivoltaic design variable. Since areas and positions were not replicated and chemical analyses were performed on composite samples, this hypothesis requires confirmation through studies with a replicated experimental design.