Amoroso, Giandomenico (2026) Advancements in amendments and biostimulant formulations from waste for enhanced soil ecosystem functionality. [Tesi di dottorato]

	Documento PDF PHD_Thesis_Amoroso.pdf Visibile a [TBR] Amministratori dell'archivio Download (4MB) | Richiedi una copia
	Documento PDF PHD_Thesis_Amoroso_Secretata.pdf Visibile a [TBR] Amministratori dell'archivio Download (5MB) | Richiedi una copia

Abstract

Modern agriculture faces the dual challenge of sustaining crop productivity while reducing the environmental footprint associated with intensive input use and agro-industrial waste accumulation. This PhD thesis investigates integrated, biochar-based strategies to improve nutrient efficiency, enhance early plant establishment, and promote circular valorization of livestock and agro-industrial by-products. The work combines seed-coating technologies, composting approaches, and biochar applications for digestate management. Innovative seed coatings were developed using biochar enriched with buffalo digestate or olive pomace and inoculated with microbial consortia of natural origin (forest litter from Fagus sylvatica, Quercus ilex, and Pinus spp.) or industrial strains (Trichoderma spp. and Clonostachys rosea). Germination assays, greenhouse trials, and field experiments on Lactuca sativa, Diplotaxis tenuifolia, Solanum lycopersicum, and Zea mays demonstrated that raw by-products induced phytotoxic effects linked to ammonia, salinity, and phenolic compounds, whereas biochar effectively mitigated these constraints by improving nutrient retention and water availability. The inclusion of Trichoderma significantly enhanced seedling establishment, root development, and biomass accumulation, confirming a synergistic interaction between biochar and microbial inocula. Rhizosphere microbiome analyses revealed that coating composition strongly influenced early microbial assembly, followed by partial soil-driven homogenization dominated by adaptive bacterial taxa. Complementary experiments evaluated biochar as a floating cover during digestate storage, demonstrating reductions in NH₃ emissions mainly through physical gas-transfer limitation, and highlighted how biochar properties govern cover stability and adsorption capacity. Digestate-enriched biochar residues subsequently functioned as soil amendments, improving biomass production in Lolium multiflorum under selected fertilization regimes. Finally, biochar-modified composts derived from buffalo manure, digestate, and olive pomace were assessed as partial substitutes for mineral nitrogen. Intermediate fertilization strategies combining compost with reduced mineral N optimized plant N uptake and biomass while maintaining higher nitrogen-use efficiency, whereas biochar primarily exerted a buffering effect on nitrate release and soil N dynamics rather than directly increasing yields. Overall, this thesis demonstrates that biochar acts as a multifunctional platform enabling the safe recycling of organic residues, targeted microbial delivery, mitigation of gaseous losses, and improved early crop performance. These integrated approaches offer scalable solutions for enhancing agroecosystem resilience while advancing circular economy principles in sustainable agriculture.

Downloads

Actions (login required)

Modifica documento