Rethinking Bloom-Risk Management in Recovering Shallow Lakes: From Visible Surface Events to Latent Risk

This is the authors' abstract. We don't add key points for this paper.

Visible surface blooms have long been the default signal for bloom surveillance and intervention in shallow lakes.This logic was useful when bloom risk appeared mainly as persistent, extensive, and readily observable cyanobacterial scums.In recovering shallow lakes, however, it can create a false sense of security.Reductions in external nutrient loading may suppress conspicuous surface events without removing the ecological and physical conditions that allow blooms to re-emerge. 1 Recovering shallow lakes are considered here as a specific management setting rather than as a proxy for all lake types.Their strong sediment-water coupling, wind-driven resuspension, internal nutrient recycling, nearshore retention, hydrodynamic convergence, and vertical redistribution of biomass can sustain bloom-forming capacity even as the surface appears to be clearer.The problem is not only technological; it is conceptual.Recent advances in satellite detection, high-frequency in situ sensing, vertical profiling, hydrodynamic-ecological modeling, machine-learning prediction, molecular detection, toxin analysis, and automated early warning systems enable better bloom detection and biomass estimation.These technologies also support risk-area delineation, model-based forecasting, emergency response, and long-term trend assessment.1,2 However, many operational approaches still organize risk around visible events, threshold exceedance, or predicted bloom occurrence.During recovery, nutrient regimes, sediment feedbacks, phytoplankton composition, and watercolumn stability can reorganize at different rates, allowing biomass and toxin hot spots to shift from historically monitored open-water surfaces to subsurface layers, nearshore Viewpoint pubs.acs.