Wind-driven sediment disturbance controls basin-scale internal phosphorus loading in Lake Chaohu: a remote sensing—constrained framework

Internal phosphorus loading from sediments is strongly regulated by hydrodynamic disturbance and temperature-dependent biogeochemical processes in shallow lakes, yet basin-scale quantification remains constrained by limited observations and scaling uncertainties. Here, a hydro-biogeochemical framework was developed and evaluated for Lake Chaohu, China, by coupling wind-driven sediment disturbance with temperature-dependent biogeochemical kinetics and constraining the spatial disturbance response using Sentinel-2 observations. A multivariate disturbance function ( Ψ ), derived from in situ and satellite observations, was used to characterize spatial variability in sediment resuspension under wind forcing and combined with shear-stress-normalized flux formulations to reconstruct daily phosphate release rates. Applied to Lake Chaohu, the framework showed good agreement with observation-constrained estimates of sediment phosphate release ( k = 0.81, R 2 = 0.82), capturing both seasonal variability and episodic wind-driven fluctuations. The reconstructed release patterns were consistent across the western, central, and eastern regions of the lake, supporting the use of the framework for regional-scale estimation within Lake Chaohu. The results demonstrate how meteorological forcing, sediment disturbance, and temperature-dependent processes can be integrated with satellite observations to extend experimentally constrained estimates of sediment phosphate release across space and time. Further evaluation across lakes with contrasting sediment and optical properties is needed to determine the broader applicability of the framework.