Vermicomposting of coffee pulp using the earthworm Eisenia fetida: effects on C and N contents and the availability of nutrients

• Published in: Biology and fertility of soils 1996-04, Vol.22 (1/2), p.162-166
• Main Authors: Orozco, F.H, Cegarra, J, Trujillo, L.M, Roig, A
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Animal productions; Biological and medical sciences; boron; calcium; calcium-magnesium ratio; carbon; chemical composition; coffee pulp; composts; earthworms; Eisenia fetida; exchangeable cations; fertilizer value; Food industries; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; inorganic ions; Invertebrates; magnesium; magnesium-potassium ratio; nitrogen content; nutrient availability; nutrient content; organic fertilizers; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Others; phosphorus; population density; potassium; quality; ratios; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Terrestrial animal productions; Use and upgrading of agricultural and food by-products. Biotechnology; vermicomposting; waste utilization; water content
• ISSN: 0178-2762; 1432-0789
• DOI: 10.1007/bf00384449

In Colombia, more than 1 million tons of coffee pulp are produced every year. Its transformation into compost by means of turned piles has led to a final product with poor physical and chemical characteristics and vermicomposting has been suggested as an alternative method of transforming these wastes into a useful organic fertilizer. The ability of the earthworm Eisenia fetida to transform coffee pulp into a valuable compost was evaluated. The influence of bed depth and time on different C fractions, N content and availability of nutrients was studied. The results showed that the C and N contents were not affected by the depth of the bed, whereas time affected both. An increase in the fractionation ratio, determined by calculating the C in the fraction smaller than 100 micrometer as a percentage of C in the samples as a whole, and low values of humic-like substances were recorded during vermicomposting. After ingestion of the pulp by the earthworms, an increase in available P, Ca, and Mg but a decrease in K were detected.