Genistein combined polysaccharide

Application of solidified dredged sludge for constructing ecological slope protection represents a vital strategy for sustainable utilization of river sludge. Evaluating the environmental characteristics of solidified river sludge under prolonged exposure to natural conditions is essential for assessing its ecological safety and practical applicability. In this study, conventional cement (CC) and a novel composite solidifying agent (GCP) were employed to stabilize river sludge. Impact of natural rainfall erosion on the physicochemical properties and environmental characteristics of the solidified sludge was examined. Particular focus was placed on the release patterns of water pollutants, including nitrogen, phosphorus, and heavy metals from both types of solidified sludge under natural rainfall exposure. The results showed that rainfall erosion reduced the strength and pH of the solidified sludge, affected the immobilization effect of heavy metals, nitrogen, phosphorus, and promoted their release. Compared with CC, GCP exhibited better immobilization effects on pollutants and a stronger buffering capacity against rainfall erosion. The compressive strength of the GCP solidified sludge (GCPSS) after rainfall erosion was 1.35 times greater than that of the CC solidified sludge (CCSS). The concentrations of total phosphorous and nitrogen in the GCPSS decreased significantly under the action of multiple rainfall events. Cynodon dactylon cultivated on the GCPSS demonstrated superior growth performance, accompanied by greater microbial diversity and abundance. Notably, the populations of Pseudolabrys, Gaiella, and Bacillus were enriched, contributing positively to soil stability. In contrast, the microbial community in the CCSS exhibited no significant variation. These findings are important for assessing the feasibility and environmental safety of utilizing solidified river sludge in the construction of ecological slope protection.