Engineering Evaluation of Microbe-Material Synergistic In-situ Remediation for Campus Landscape Lakes

Campus landscape lakes are vulnerable to combined organic and nutrient pollution because of weak hydrodynamics and limited self-purification capacity. Conventional in-situ remediation often suffers from rapid material loss and short treatment duration. This study evaluated the engineering applicability of microbe-material synergistic remediation through integrated analysis of 28 published field cases and a field investigation of a campus artificial lake in Nanning, China. The integrated results showed removal efficiencies of 82.7% for NH4+-N, 76.4% for COD, and 68.5% for TP. Dissolved oxygen (DO) was identified as a key influencing factor, and COD removal was markedly improved when DO exceeded 2 mg/L. Field monitoring indicated low-oxygen combined pollution, while historical records showed that direct material dosing led to a loss rate of over 60% and an effective treatment duration of less than three weeks. A gel microsphere encapsulation strategy based on alginate and chitosan is therefore proposed to improve material retention and treatment persistence.