CHARACTERIZATION OF SOLID AND LIQUID FERTILIZERS DERIVED FROM COMPOSTING ALPERUJO AND OLIVE TREE PRUNING REMAINS

Abstract

Composting is the most recommended organic waste management technique worldwide.
These residues can have various origins, they can even be the result of the industrial processing of agricultural products, such as alperujo, which results from the extraction of
oil from olives. This residue, once composted, has the potential to generate a compost of
good quality that can be used as an amendment and / or organic fertilizer. However, little
information exists regarding the quality of the compost made from alperujo with pruning
remains from olive groves. The objective of the present work was to characterize
physically, chemically and microbiologically the compost obtained from the composting of
olive residues, both in the solid (AS) and liquid (AL) form. In addition, the presence of
phytotoxic substances was analyzed through the germination test with different
horticultural species. The trials comprised four productive periods. The chemical, physical
and microbiological evaluated parameters (organic carbon, pH, electrical conductivity,
nitrogen, phosphorus, potassium, soluble cations, polyphenols, biological activity, bulk
density, particle density, porosity) are within the range considered adequate in both AS
and AL. Phytotoxic effects of LA were not detected in the evaluated species. The results
indicate that both fertilizers present highly recommended characteristics for their use as
amendment and / or organic fertilizer, and that AL is capable of promoting germination in
spinach, parsley, basil and alfalfa.