Is enrichment with inorganic and organic compounds feasible for improving the quality of vermicomposting using water hyacinth biomass?

Abstract

In eutrophic environments, aquatic weeds reproduce rapidly, occupying extensive areas of the waterbody and preventing the multiple use of water resources. The use of the biomass of these plants invermicomposting represents a sustainable alternative utilization of the excess biomass produced byeutrophication. The enrichment of macrophyte biomass during vermicomposting was tested using aninorganic solution (NPK1:75% and NPK3:50%) and an organic solution with glucose (0:25g=L and0:50g=L) to improve the quality of the vermicompost. The consumption of biomass of the macrophytesby theEisenia fetidaincreased as the vermicomposting progressed, reaching the highest values atthe end of the experimental period. The control treatment, i.e., without earthworms, remained stable.The electrical conductivity tended to increase for the treatments NPK1:75%, Glucose0:25g=L andGlucose0:50g=L. The pH of the vermicomposting tended to be neutral in all treatments. The controland inorganic treatments showed a reduction in macrophyte biomass and the number of individualsofEisenia fetida. The additions of NPK and glucose slightly improved vermicompost quality andbiomass consumption by the earthworms. However, using vermicompost alone does not meet therequirements for its use as a fertilizer. Thus, we suggest the use of vermicompost in association withother fertilizers, adding moisture and structuring the soil.

Keywords

• eichhorniacrassipes;eiseniafetida; eutrophication; glucose; humification; mathematicalmodeling; nutrients