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13 páginas.- 4 figuras.- 2 tablas.- referencias.- Supplementary data to this article can be found online athttps://doi.org/10.1016/j.scitotenv.2021.151572, This study aims to evaluate the effects of technosols made with different organic amendments to restore degraded soils in a semiarid limestone quarry. The effects on soil quality, functionality and organic matter dynamics of the technosols amended with waste of gardening, greenhouse horticultural, stabilized sewage sludge and two mixtures of sludge with both vegetable composts were assessed. Several physical and chemical properties, humus fractions, soil respiration and molecular composition was performed after 6 and 18 months. Un-amended soils, and nearby natural undegraded soils served as reference. Amended technosols increased water retention capacity, electrical conductivity, total organic carbon and nitrogen, respect to not amended and natural soils. Humus fraction composition was not altered over time. Un-amended soils, very poor in organic matter, did not show any pyrolyzable compounds or labile soil organic matter by thermogravimetry. In contrast, the pyrochromatograms of natural soils showed lignocellulosic materials, polypeptides and a noticeable presence of alkylic compounds. In technosols with both types vegetable compost, the organic matter structure was more complex, showing compounds from lignin-derived and long-chain alkyl, polysaccharides, chlorophyll isoprenoids and nitrogen. In sludge technosol, a set of sterols was outstanding. The mixtures showed a molecular fingerprint of materials derived from the decomposition of the organic amendments that formed them. These signs of the contribution of different organic matter forms derived from the amendments were also reported by the series exothermic peaks found in the calorimetry. This short-term study indicates a clear effect of the amendments on the recovery of soil organic matter and presumably of its functionality. After the amendments application, microbial activity and soil respiration rates increased rapidly but ceased 18 months later. The molecular composition of the organic matter of the soils amended with plant compost was very similar to that of natural, non-degraded soils in nearby areas., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO), and FEDER funds, through the project CGL2017-88734-R (BIORESOC) MINECO/AEI/FEDER, UE and FEDER-Junta de Andalucía Research Projects RESTAGRO (UAL18-RNM-A021-B), MarkFire (PAIDI2020, PY20_01073) and Restoration of Abandoned Agricultural Soils in Semiarid Zones to Improve Productivity and Soil Quality and Enhance Carbon Sequestration (P18-RT-4112). Isabel Miralles is grateful for funding received from the Ramón y Cajal Research Grant (RYC-2016-21191) from the Spanish Ministry of Economy and Competitiveness (MINECO), Raúl Ortega thanks his postdoctoral contract HIPATIA of the University of Almería Research Plan. Layla M. San Emeterio thanks the pre-doctoral FPI fellowship (grant number BES-2017-079811).

16 págs.- 5 figuras.- 3 tablas.- 76 referencias.- The following are available online at https://www.mdpi.com/article/10.3390/app11156684/s1 .- (This article belongs to the Special Issue Composts and Organic Wastes: Analytical Methods and Applications), An innovative approach based on the combination of analytical pyrolysis coupled with gas chromatography-mass spectrometry (Py-GC/MS) with compound-specific isotope analysis (Py-CSIA) is used to study the composting process of maize biomass. This multidisciplinary approach aims to elucidate the decomposition rate of the main biogenic materials (lignin, cellulose, proteins, lipids, and waxes) responses to the composting process. According to Py-GC/MS data/structural composition, a noticeable and significant decrease during the first stage of the composting process of carbohydrates and aromatic compounds is found, followed by a gradual increase of all compounds till the end of the experiment. This trend, along with an increase of fatty acids methyl-ester at the first composting stage, sustains the microbial activity and its stabilization over time. Py-CSIA data showed a significant enrichment in 13C in all identified compounds over time, supporting the semi-quantitative results and the decomposition of initial biomass throughout the composting process. This trend is also perceptible in lignin moieties, long-chain aliphatic structures, and isoprenoids, as highly recalcitrant compounds, presumably due to depolymerization and carbon translocation of side-chain molecules during the composting process. Compound-specific isotope values showed a good correlation with the bulk isotope data, and this served as validation of the technique. However, bulk values showed higher heterogeneity because those represent an average of all organic compounds in the sample. By combining isotopic and structural information using Py-GC/MS and Py-CSIA, we are able to provide further information and a more detailed approach to the study of the decomposition process of biomass by considering the diverse dynamics of the main biogenic compounds., This research was funded by the Spanish Ministry of Economy and Competitiveness (MINECO) with the pre-doctoral FPI fellowship (grant number BES-2017-079811) to L.M.S.-E. and by Junta de Andalucía project MarkFire (PAIDI2020, PY20_01073). Both projects are co-funded with EU FEDER funds.

7 páginas.- 4 figruas. 5 tablas.- 32 referencias.- Supplementary material related to this article can be found, in the online version, at doi:https://doi.org/10.1016/j.scienta.2019.109120, Cherimoya, a tropical fruit from South America whose commercial demand is increasing for both its exceptional flavor and high nutritional content, is expanding in cultivation to subtropical areas such as the Mediterranean coast of Andalusia (Spain). In this paper, we analyze cherimoyas (peel, pulp, and seed) grown in Almunecar (Granada, Spain) during the years 2013, 2015, and 2016 from trees applied with different pruning wastes (avocado, cherimoya, mango, and garden). The cherimoya fruits had high contents in most of the macronutrients, especially K, Ca, and micronutrients such as Fe and Zn. The Na, P, K and Ca concentrations were related to the plant mulch that released nutrients to the soil and led to a variation in soil-nutrient bioavailability by decreasing the soil pH. The seed was the part of the cherimoya that registered the least nutritional change due to annual weather differences and the highest positive effects of mulching in terms of increased nutrient availability after mulching., Authors appreciate the financial support of this work by the Spanish Ministry of Economy and Competitiveness (Project CGL-2013-46665-R) and the European Regional Development Fund (ERDF).