Effects of solar parks on soil quality, CO2 effluxes and vegetation under Mediterranean climate

Abstract

Solar energy is increasingly used to produce electricity in Europe, but the environmental impact of constructing and running solar parks (SP) is not yet well studied. Solar park construction requires partial vegetation removal and soil leveling. Additionally, solar panels may alter soil microclimate and functioning. In our study of three French Mediterranean solar parks, we analyzed 1) effects of solar park construction on soil quality by comparing solar park soils with those of semi-natural land cover types (pinewood and shrubland) and abandoned croplands (abandoned vineyards); 2) the effect of solar panels on soil microclimate, CO2 effluxes and vegetation. We measured 21 soil properties of physical, chemical, and microbiological soil quality in one solar park and its surroundings to calculate integrated indicators of soil quality. We surveyed soil temperature and moisture, CO2 effluxes and vegetation below and outside solar panels of three solar parks. Soil aggregate stability was reduced by SP construction resulting in a degradation of soil physical quality. Soil chemical quality and a general indicator of soil quality were lower in anthropogenic (SP and abandoned vineyards) than in semi-natural (pinewood and shrubland) land cover types. However, differences between abandoned vineyards representing the pre-construction land cover type and solar parks were not significant. Solar panels reduced the soil temperature by 10% and soil CO2 effluxes by 50% but did not affect early successional plant communities. Long-term monitoring is needed to evaluate the effects of solar panels on vegetation.

Does soil matter?

“…12 (1-2) Climate Plan (2020) will be met in 2026, installed capacity of 9,000 MW can realistically be achieved by 2030. Despite the increasing importance and extent of solar parks, the environmental effects of their construction and operation have not yet been properly investigated (Zhang H. et al 2023, Lambert 2021, Turney & Fthenakisz 2021. Research draws attention to the negative changes in soils (Choi et.…”

“…After installation, the parts of the area shaded by the panels can affect up to 25-47% of the total area of the solar park (Ong 2013). Here, the microclimatic conditions change, which affects soil moisture, surface temperature, the carbon cycle and the physical, chemical and microbiological properties of soil (Barron-Gafford et al 2016, Lambert 2021). However, after proper planning and implementation, solar parks can offer unique opportunities for the benefit of the local environment and biological diversity (Fthenakis 2011, Hernandez et al 2019, Blaydes et al 2021.…”

Dynamic variation and patterns of soil moisture in desert PV power station construction

“…Any small change in available water will have a fatal impact on plant growth. At the same time, the microclimate under the PV panel may also change the composition of plant community and soil respiration process [9].…”