EFFECT OF CHEMICAL INDICATORS AND RESPIRATORY ACTIVITY ON THE RESIDENCE TIME OF VERMICOMPOSTS | EFFECT OF CHEMICAL INDICATORS AND RESPIRATORY ACTIVITY ON THE RESIDENCE TIME OF VERMICOMPOSTS

English. Vermicompost is considered an environmental quality for managing agricultural residues since it improves soil structure, provides nutrients, and helps to reduce environmental impact. The objective of this study was to determine the residence time using a kinetic model of carbon mineralization while also evaluating chemical and biological parameters obtained during vermicompost processing. Earthworms (Eisenia fetida) were used comparing different doses of residual sludge (LR) at 0, 10, 20, and 40 Mg, keeping constant the dose of domestic waste (RD) and cattle manure (EV) at a ratio of 1:1 (dry basis). An AxB factorial design was used, where A represented the LR dose and B the type of residues (RD and EV); thus, eight treatments with nine replicates were compared. The pH, organic matter (MO), total nitrogen, C/N ratio, respiratory activity, C mineralization, and residence time were determined. The results of the treatments indicate a slightly alkaline trend. MO was different among treatments, with a higher MO percentage in EV and LR with 40 Mg of LR (28.92 ± 10.78 %, F(7,88) = 2.63, p ≤ 0.01). The total N percentage was low, but the treatment containing 40 Mg of LR and RD (1.04 ± 0.62 %, F(7,88) = 3.87, p < 0.01) stood out. C/N ratios < 20, which indicate stability, were recorded in the treatments with LR and EV. The vermicompost obtained from 40 Mg of LR and EV complied with a minimum residence time (less than 70 days) throughout processing, making it an excellent choice for agricultural use.

Spanish; Castilian. Vermicompost is considered an environmental quality for managing agricultural residues since it improves soil structure, provides nutrients, and helps to reduce environmental impact. The objective of this study was to determine the residence time using a kinetic model of carbon mineralization while also evaluating chemical and biological parameters obtained during vermicompost processing. Earthworms (Eisenia fetida) were used comparing different doses of residual sludge (LR) at 0, 10, 20, and 40 Mg, keeping constant the dose of domestic waste (RD) and cattle manure (EV) at a ratio of 1:1 (dry basis). An AxB factorial design was used, where A represented the LR dose and B the type of residues (RD and EV); thus, eight treatments with nine replicates were compared. The pH, organic matter (MO), total nitrogen, C/N ratio, respiratory activity, C mineralization, and residence time were determined. The results of the treatments indicate a slightly alkaline trend. MO was different among treatments, with a higher MO percentage in EV and LR with 40 Mg of LR (28.92 ± 10.78 %, F(7,88) = 2.63, p ≤ 0.01). The total N percentage was low, but the treatment containing 40 Mg of LR and RD (1.04 ± 0.62 %, F(7,88) = 3.87, p < 0.01) stood out. C/N ratios < 20, which indicate stability, were recorded in the treatments with LR and EV. The vermicompost obtained from 40 Mg of LR and EV complied with a minimum residence time (less than 70 days) throughout processing, making it an excellent choice for agricultural use.