Wind farm-induced redistribution of soil organic matter: Molecular insights into dissolved organic matter and microbial interactions

Wind energy has become a cornerstone of renewable energy development, yet its environmental impacts on soil systems remain insufficiently understood. In particular, how long-term wind farm operation influences organic matter dynamics at the molecular level has received limited attention. In this study, we first surveyed three onshore wind farms across distinct climatic zones in China and found that long-term wind farm operation significantly enriched soil organic carbon, total nitrogen, nitrate‑nitrogen, and ammonium‑nitrogen within operational zones compared to undisturbed reference areas. Based on this, we focused on one inland wind farm with the highest wind energy potential and the most complete wind regime records as a case study site, to explore the molecular composition and transformation of dissolved organic matter (DOM) in greater depth. By integrating ultrahigh-resolution Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), spectroscopic analyses, and high-throughput sequencing, we reveal that wind-induced microclimatic shifts may contribute to a significant fertile island effect, characterized by increased nutrient availability and enhanced carbon accumulation in wind farm soils. Wind-driven physical transport further shapes the spatial differentiation of DOM: upwind areas are characterized by highly oxidized and humified DOM components, whereas downwind areas accumulate fresh, labile organic compounds. This gradient also drives a transition in microbial trophic strategies, from oligotrophic taxa dominating upwind soils to copiotrophic taxa thriving downwind, with their distinct substrate preferences reinforcing DOM spatial heterogeneity. These findings offer molecular-level insights into wind farm-induced alterations in soil carbon cycling and underscore the need to incorporate biogeochemical perspectives into environmental assessments of renewable energy infrastructure.