2026-08-01 JOURNAL OF ENVIRONMENTAL SCIENCES 2026 166(卷), null(期), (331-343页)
Understanding nitrogen (N) biogeochemical cycling within the unsaturated-saturated zone of lakeshores in semiarid deserts is critical for maintaining lake ecosystem equilibrium, yet remains poorly studied. Results revealed significant vertical gradients in N fractions, with higher concentrations in the unsaturated versus saturated zone. Quantification of functional genes across seven N cycles identified ammonification and denitrification genes as most abundant. Nitrification rates decreased vertically (surface to depth) but increased horizontally along the groundwater flow path, while denitrification rates showed the opposite pattern. Temperature and functional genes were key nitrification drivers; total organic carbon explained 49.8 % of denitrification rate variation. Crucially, denitrification represented 34.76 %-38.92 % of the total N cycling potential, indicating its key role in mitigating lake eutrophication via N removal in the lakeshore zone. We propose a conceptual model of these N processes specific to semiarid desert lakeshores. These findings enhance regional environmental quality assessment and lakeshore ecosystem service representation.