QUALITY ASSESSMENT OF COMPOST PREPARED WITH BY-PRODUCT OF THE OLIVE OIL INDUSTRY - AGRONOMIC APPLICATION IN OLIVE GROVE
The industrial olive oil sector is very important in Mediterranean countries. The two-phase centrifugation system for olive oil extraction, from the early 1990s, has introduced a new solid waste called two phase olive mill waste (alperujo). The new waste is generated in large quantities during a short period the time, leading to serious management problems. Different solutions have been proposed for two phase olive mill waste treatment based on evaporation ponds, thermal concentration, phenolic components extraction, application to agricultural soils to sorption of herbicides and insecticides. Composting as a method for preparing organic fertilizers and amend¬ments is economically and ecologically sound and may well represent an acceptable solution for disposing of two phase olive mill waste, at the same time increasing its value. In the present work, we studied the effect of the addition of compost made from two phase olive mill waste on the nutritional status and yield of an olive grove. The objective was to optimize the composting conditions and to evaluate the changes in mineral nutrient (N, P and K) concentrations on plant and yield, after agronomic application of compost. The compost was prepared in a pilot-plant using the turning-pile system. Temperature and moisture were used as monitoring parameters to follow the composting progress, which underwent the typical trend of two phase olive mill waste composting mixtures. The results showed a similar evolution of the mixture of the two phase olive mill waste and olive leaf as bulking agents. The quality of the mature compost was assessed by the following parameters: N, P, K, pH, electrical conductivity and C/N ratio. The compost showed a large and balanced concentration of mineral elements for its use in agriculture. The application of compost on olive grove maintained the nutritional status of the olive trees to an optimum level. So, the use of compost of two phase olive mill waste represents an important tool for fertilization requirements of olive orchards.
Fernández-Hernández , A., García-Ortiz Civantos, C., Serramiá, N., Roig , A. and Sánchez-Monedero, M.A. (2011). QUALITY ASSESSMENT OF COMPOST PREPARED WITH BY-PRODUCT OF THE OLIVE OIL INDUSTRY - AGRONOMIC APPLICATION IN OLIVE GROVE. Acta Hortic. 924, 241-246
olive-mill by-product "alperujo", agronomic application, plant nutrient content, compost, olive orchards