COMBINING CO-COMPOSTING AND VERMICOMPOSTING FOR THE EFFECTIVE TREATMENT OF PINEAPPLE AND SHEEP RESIDUES

García-Ortega S., Olivares-Gonzalez E.

Universidad del Papaloapan, Loma Bonita, Oaxaca, México

Green waste derived from pineapple (Ananas sp.) processing has been used as forage for cattle by farmers in the Papaloapan area of Mexico (Aw2 climate). The work described here explores an alternative use of this pineapple-derived green waste as a potential soil ameliorant to enhance soil quality. Traditionally, farmers in the study area have used sheep-derived manure as a fertilizer to enhance pasture quality. However, due to the environmental and sanitary consequences associated with manure accumulation in sheep housing (e.g. risk of zoonotic disease) this is not the best option. The main aim of this work is to combine the precomposting of pineapple and sheep residues with subsequent vermicomposting to obtain a stable organic fertilizer. Precomposting of sheep manure and pineapple green waste was done in three ratios (1:1; 2:1; and 3:1), over a period of 12 weeks followed by vermicomposting for a further 12 weeks. Time trials were employed to determine the growth and reproduction of Eisenia foetida in material precomposted for various periods of time. Also, earthworm preference trials were undertaken in triplicate.  Our results showed that E. foetida was capable of achieving good rates of growth and reproduction in the co-composted pineapple green waste and sheep manure substrates. Combining traditional composting practices with vermicomposting may provide an option to produce an organic fertilizer of higher quality (e.g. reduced pathogen load and better nutrient content and balance). Further work is therefore necessary to test the organic fertilizers in vegetable production.