Long‐Term Operation of Photovoltaic Power Stations Promotes Soil Carbon Sequestration but Induces Stoichiometric C:N:P Imbalance in Desert Ecosystems

Soil carbon‐nitrogen‐phosphorus (C:N:P) stoichiometry governs nutrient cycling and carbon sequestration in desert ecosystems, yet how large‐scale photovoltaic (PV) deployment, a cornerstone of global carbon neutrality, shifts these stoichiometric balances and whether such shifts enhance or degrade long‐term land function remain unresolved over decadal timescales. To resolve this uncertainty, this study selected six photovoltaic power stations with operational durations of 1, 3, 7, 9, 12, and 14 years, quantified the contents of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), and the variations of their stoichiometric ratios across three microhabitat types (under panels, SUP; between panels, SBP; panel‐front leading edges, PFL), and identified their key environmental drivers. Results showed that SOC, TN, and TP contents significantly increased across all panel positions with prolonged PV operation. Crucially, by year 14, we identified a pronounced asymmetric accumulation pattern: SOC accumulated significantly faster (increasing by 182.61%–204.35% relative to control) compared to TN (37.31%–54.48%) and TP (50.11%–80.23%). This asymmetric accumulation led to a significant rise in C:N and C:P ratios, signifying a progressive shift toward stoichiometric C:N:P imbalance, particularly in the SUP microhabitat. Both random forest and PLS‐PM analyses identified operation duration and panel position as the primary drivers of these stoichiometric shifts, mediated by soil available nutrients. Climatic factors exerted positive effects on TP accumulation but negative effects on SOC, C:P, and N:P ratios. This study reveals that while long‐term photovoltaic operation significantly enhances carbon sequestration, it concurrently induces stoichiometric C:N:P imbalance. These findings highlight the necessity of implementing position‐specific management (e.g., targeted nutrient regulation) to mitigate nutrient imbalance risks, thereby ensuring the long‐term stability and sustainability of desert PV carbon sinks.