Elucidation of functional chemical groups responsible of compost phytotoxicity using solid-state C-13 NMR spectroscopy under different initial C/N ratios

Elucidation of functional chemical groups responsible of compost phytotoxicity using solid-state C-13 NMR spectroscopy under different initial C/N ratios Azim K. auteur aut IRD Faissal Y. auteur aut IRD Soudi B. auteur aut IRD Perissol C. auteur aut IRD Roussos Sevastianos auteur aut IRD Alami I. T. auteur aut IRD text journalArticle eng text/pdf born digital access More than 1 million tons of fresh organic wastes is produced in the Souss-Massa region in Morocco. Tomato organic residues represent more than 25% of the total organic wastes and are deposited in uncontrolled landfills. Thus, composting can represent a valuable and pertinent solution to this environmental problem. The objectives of this experiment are to identify the potential functional groups responsible for compost phytotoxicity and to determine the optimum initial carbon to nitrogen ratio (C/N) for maximum recovery of tomato residues. The experiment consisted of the variation of the initial C/N ratios (25, 30, 35, and 40) using mixtures of different raw materials (tomato residues, melon residues, olive mill pomace, and sheep manure). Physicochemical parameters (pH, electrical conductivity, C/N ratio, and humic acid/fulvic acid ratio) were determined and spectroscopic analyses (UV-vis and NMR-C-13) were performed during the composting process along with quality parameters (germination and phytotoxicity tests) at the end. The results showed that the compost with the initial C/N ratio of 35 is the most humified with the least phytotoxic effect. The germination and phytotoxicity tests were negatively correlated with the methoxyl/N-alkyl-C ratio and O-alkyl-C. These two functional groups are probably the origin of phytotoxicity expression in compost quality tests. Thus, a simple and precise quality test could be performed to evaluate directly the phytotoxicity and maturity of compost. specialized NMR-C-13 Tomato residue Compost Phytotoxicity C/N ratio MAROC 020 076 021 Environmental Science and Pollution Research 25 4 3408-3422 2018 0944-1344 https://www.documentation.ird.fr/hor/fdi:010072363 10.1007/s11356-017-0704-9 0944-1344 [F B010072363] https://www.documentation.ird.fr/hor/fdi:010072363 https://www.documentation.ird.fr/intranet/publi/2018/03/010072363.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2018-04-03 2023-07-11 fdi:010072363 fre