Application and exploration of garbage enzymes in soil remediation of multiple heavy metal pollution

[Objective] To assess the bioremediation potential of garbage enzymes in heavy metal-contaminated lead-zinc mine soils. [Method] A pot experiment evaluated garbage enzymes application effects on: (1) Pb/Zn/Cd bioavailability and phytoavailability, (2) soil fertility parameters, (3) soil enzyme activities, and (4) physiological responses of Chinese cabbage. [Results] Garbage enzymes significantly reduced heavy metal bioavailability, decreasing leaf Pb/Zn/Cd concentrations by 66.8%/17.6%/37.4% and root levels by 34.3%/23.4%/46.8% versus controls. Soil fertility improved substantially, with available N/P/K increments of 2.43-31.2%, 1.86-45.5%, and 3.40-22.3%, respectively. Key soil enzymes (urease, sucrase, catalase, phosphatase) exhibited enhanced activities. Garbage enzymes treated plants showed increased biomass (fresh weight), chlorophyll (21.8%), and soluble sugars, alongside reduced stress markers: nitrate-N (-24.3%), malondialdehyde (-33.6%), proline (-18.9%), and superoxide dismutase (-42.1%). [Conclusions] Garbage enzymes demonstrate dual functionality in metal immobilization and soil revitalization, offering an eco-sustainable solution for restoring agricultural productivity in contaminated ecosystems.