Establishing a nutrient flow and finding alternative sources of phosphorus is essential to maintaining high agricultural productivity and food security in the future, when humanity could deplete readily available phosphorus ore reserves. Phosphorus and other nutrients contained in human excrements are currently being largely discarded as waste although they can be a good source for crop production. By 21-day trial of vermicomposting of black water mixed into a matrix of compost and sawdust, we found that earthworms accelerate the mineralization of nutrients, but for the production of quality vermicompost longer processing than 21 days or higher concentration of earthworms in the substrate is required. Addition of black water increases the concentration of available phosphorus in the finished vermikompost. Earthworms increase the concentration of available phosphorus by an average of 11-24 %. Vermicomposting within 21 days does not lead to sufficient reduction of pathogens to meet the standards for use in crop production. In carrying out the preliminary experiment, we found that photo documentation of the experiment in the form of time lapse video is a good method of presenting the experiment, which gave us an insight into the progress of the vermicomposting process.
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