Potential ecological impacts of floating photovoltaics on lake biodiversity and ecosystem functioning

The need to mitigate the effects of climate change is accelerating the development of novel technologies such as floating photovoltaics (FPV). Despite FPV being identified as an emerging issue of concern for biodiversity conservation, it is fast spreading globally and our understanding of their potential ecological impacts is limited. We present an overview of the current knowledge and provide an ecological perspective on FPV potential impacts on lake biodiversity and ecosystem functioning. To date, published works have highlighted reductions in light arrival, wind speed and water temperature with increased FPV cover but the subsequent cascading effects on biological and ecological processes remain unknown. We suggest that modifications in light and water temperature can alter individual regulatory processes affecting, primary production and energy transfer within lake food webs. Additionally, FPV can modify the thermal functioning and oxygenation of the water column while providing artificial habitats for organisms. These modifications can affect individual behavior and life-story but also alter the composition of plant and animal communities, trophic interactions and greenhouse gas balances. We suggest that FPV can also modify socioecological activities related to lake use (e.g., angling, leisure) and pressures at the meta-ecosystem level. Overall, we argue that FPV impacts will be highly context-dependent, varying across ranges of environmental conditions and industrial characteristics (e.g., FPV cover and location). Given the ecological and socio-economic implications of FPV, empirical quantifications based on robust designs are urgently needed and we provide here a unique guideline to help developing research programs to monitor these potential impacts.