Gelsomino Antonio, Petrovičovà Beatrix, Panuccio Maria Rosaria
Department of Agricultural Sciences, Mediterranean University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy.
Department of Agricultural Sciences, Mediterranean University of Reggio Calabria, Feo di Vito, 89124 Reggio Calabria, Italy.
Sci Total Environ. 2024 Jan 1;906:167633. doi: 10.1016/j.scitotenv.2023.167633. Epub 2023 Oct 6.
Fire-extinguishing powders (FEPs) are constituted by an inner mineral core of (NH)HPO and (NH)SO salts (>95 %, by weight) externally coated with Si-based additives, which make problematic reuse after their service life has expired (36 months). This study aimed to assess the feasibility of using the composting process as an environmentally friendly strategy to lyse the external coating and recycle this nutrient-rich solid waste for replacement of inorganic fertilization in soilless cultivation of horticultural crops. A microcosm-scale experiment with lettuce plants grown into a soil/quartz sand mixture under controlled conditions for 28 days was used to investigate plant responses (fresh and dry biomass, chlorophyll fluorescence parameters, root morphology, ash and nutrients content) to amendment with increasing dosages (equivalent at 0, 10, 20 and 30 t ha) of an exhausted FEPs-enriched compost. Chemical properties (pH, EC, TOC, TN) and content of soluble nutrients (Na, K, Mg, Ca, NH, HPO, SO, NO, Cl) released into the growing substrate were also monitored. Non-amended microcosms and non-enriched compost treatments were taken as controls. Results showed, beside the expected rise of phosphate, sulphate and ammonium ions, exhausted FEPs contributed Ca, Mg and Na content. Whereas compost determined a dose-dependent release of K, which was particularly useful in maintaining the K/Na ratio in a range not harmful to plant physiology. It was also found that the compost enriched with 5 % (w/w) exhausted FEPs was no phytotoxic to lettuce. On the contrary, it stimulated the plant growth, increased the photosynthetic efficiency and the shoot biomass accumulation, thus incrementing the shoot/root ratio. Moreover, it oriented the root morphology development and promoted the plant uptake of both water and solutes. To sum up, composting represents a suitable alternative to chemical treatment to recover readily available nutrients contained in exhausted FEPs and produce an enriched compost for use in soilless cultivation.
灭火粉末（FEPs）由内部的（NH₄）₂HPO₄和（NH₄）₂SO₄盐矿物核心（重量>95%）组成，外部涂覆有硅基添加剂，这使得它们在使用寿命到期（36个月）后难以再利用。本研究旨在评估使用堆肥过程作为一种环境友好策略来分解外部涂层并回收这种营养丰富的固体废物，以替代园艺作物无土栽培中的无机肥料的可行性。在受控条件下，用生菜植株在土壤/石英砂混合物中生长28天的微观尺度实验，来研究植物对添加不同剂量（相当于0、10、20和30 t·ha）的废弃FEPs富集堆肥的反应（鲜重和干重生物量、叶绿素荧光参数、根系形态、灰分和养分含量）。还监测了释放到生长基质中的化学性质（pH、电导率、总有机碳、总氮）和可溶性养分（钠、钾、镁、钙、铵、磷酸氢根、硫酸根、硝酸根、氯离子）的含量。未添加堆肥的微观世界和未富集堆肥的处理作为对照。结果表明，除了预期的磷酸根、硫酸根和铵离子增加外，废弃FEPs还增加了钙、镁和钠的含量。而堆肥则导致钾的剂量依赖性释放，这对于将钾/钠比维持在对植物生理无害的范围内特别有用。还发现，富含5%（w/w）废弃FEPs的堆肥对生菜没有植物毒性。相反，它刺激了植物生长，提高了光合效率和地上部生物量积累，从而增加了地上部/根部比例。此外，它引导根系形态发育，促进植物对水分和溶质的吸收。总之，堆肥是化学处理的合适替代方法，可回收废弃FEPs中易于利用的养分，并生产用于无土栽培的富集堆肥。
