Résumé
Solar parks require large areas to produce sufficient electricity, affecting plants and soil through changes in microclimatic conditions, in particular light reduction. Solar parks need to be managed by grazing or mowing to avoid overgrowth of solar panels. Both microclimate changes and management may affect pant communities, soil fauna and biological activity, and thus potentially change local ecosystem functioning. This study analysed plant functional traits (morphology, chlorophyll), soil physicochemical characteristics (nutrients, density, moisture, temperature), mesofauna communities (mites and springtails), and soil respiration by comparing three treatments (under solar panels, between panel rows and in continuously unshaded areas (outside) within twenty solar parks located in two southern French regions of different climate. We found that soil respiration and mesofauna abundance were 62 % and 38 % lower, respectively, under panels compared to areas outside solar panels. The community-weighted mean of chlorophyll content, lateral spread, leaf length, leaf height, and specific leaf area increased significantly under the panels with differences depending on management and region. With differences depending on management and region panel effects on soil respiration were independent of management and region in our path analysis, soil mesofauna abundance was particularly reduced under panels of mown solar parks. It is crucial to understand how solar park management interacts with the effects of solar panels on plant and soil biodiversity in order to develop strategies that reduce ecological impact while maintaining ecosystem functions.