Remedios Albiach

Composts and Organic By-Products in Pinus halepensis Forestry

In the sustainable organic waste management context, this study was carried out to explore the potential of easily available composts and organic by-products for Pinus halepensis forestry in Mediterranean areas. The study consisted in four experiments using locally abundant organic waste: experiments I and IV evaluated their suitability as fertilizers for nurseries and pine replanting respectively; experiment II considered vermicompost efficiency as a root-growth promoter; experiment III assessed the aptitude of organic waste as a component of forestry substrates. Different plant measurements, morphological attributes and analytical determinations were used to assess seedling quality and to evaluate substrates and fertilizers’ aptitude. Fertilization experiments run under nursery conditions showed that organic waste produced plantlets with similar morphological and nutritional states to mineral products with good quality standards. In pine replanting, organic fertilization clearly increased soil organic matter levels, enhancing soil nutritional and structural conditions. When evaluating different mixtures as substrate, no large differences appeared among treatments, except for the seedlings grown in virgin or recycled coconut fiber, where greater aerial development was achieved. Further research is needed to comprehend why the use of vermicompost as a root-growth promoter did not produce the expected effects. The obtained results indicate that organic by-products and composts can substitute the mineral fertilizers and substrates usually employed in the Mediterranean Region in P. halepensis forestry to contribute to develop a local circular economy.