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Located at the centre of the foremost mining district on the Iberian Peninsula (the South-Western Iberian Pyrite Belt), the settlement of Cabezo Juré (Alosno, Huelva, Spain), some 2 ha in area, represents the occupational model that... more
Located at the centre of the foremost mining district on the Iberian Peninsula (the South-Western Iberian Pyrite Belt), the settlement of Cabezo Juré (Alosno, Huelva, Spain), some 2 ha in area, represents the occupational model that structures the organisation of this mining territory (Nocete, 2006). The excavation of over 50 % of it's surface, fourteen radio-carbon dating taken through its building sequence and a systematic and integral study of its site, show that there were two stages in its occupation (Nocete et al., 2011). The first stage (Phases I, II, and III) has a time-scale covering the first three quarters of the Fifth millennium Cal BP and shows a settlement exclusively dedicated to mining and metallurgical activities that is fortified and has a local source (< 1 km) of copper ores with the technology for complex copper-working (furnaces, tuyères, crucibles, slag, smelting hammers, artefacts partway through the production process, etc.) and a marked technical and...
Poster P37 presentado en las 13 Jornadas de Analisis Instrumental, celebradas del 14-16 de noviembre 2011, en Barcelona, Espana.-- cmartin@irnase.csic.es
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The determination of heavy metals in soils and organic amendments, such as compost, manure, biofertilizer, and sludge, generally involves the digestion of samples with aqua regia, and the determination of those in the solution using... more
The determination of heavy metals in soils and organic amendments, such as compost, manure, biofertilizer, and sludge, generally involves the digestion of samples with aqua regia, and the determination of those in the solution using various techniques. Portable X-ray fluorescence (PXRF) has many advantages in relation to traditional analytical techniques. However, PXRF determines the total elemental content and, until now, its use for the analysis of organic amendments has been limited. The objective of this work is the calibration of a PXRF instrument to determine the aqua regia-soluble elemental contents directly in solid samples of organic amendments. Our proposal will avoid the digestion step and the use of other laboratory techniques. Using a training set of samples, calibration functions were obtained that allow the determination of the aqua regia-soluble contents from the PXRF readings of total contents. The calibration functions (obtained by multiple linear regression) allow...
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It is well known that humic acids (HAs) have a complex heterogeneous composition which depends not only on the precursor organic constituents but to large extent on the environmental factors in the soil system. In this study, an ‘omic’... more
It is well known that humic acids (HAs) have a complex heterogeneous composition which depends not only on the precursor organic constituents but to large extent on the environmental factors in the soil system. In this study, an ‘omic’ approach was carried out taking advantage of the information from different data matrices obtained by analytical pyrolysis of HAs. It was intended to readily infer tentative environmental information avoiding complex, time-consuming spectral interpretations and supervised data processing. This approach is based on comparing the information extracted from data tables with compounds assemblages after HA degradation by (i) multivariate data treatments, mainly multidimensional scaling (MDS) and correspondence analysis, (ii) partial least squares (PLS) regression where the variable importance for projection (VIP) method was applied in order to identify the more informative chromatographic peaks and (iii) PLS-VIP method applied to ‘rebuilt pyrolysis-mass spectra’, i.e. to arrays consisting of one average mass spectra (2–60 min) of the total ion gas chromatogram. When the results obtained from approach (iii) were compared with those from approaches (i) and (ii), we realize the possibility for a tentative prediction of the relative amounts of almost all major families of degradation compounds and large number of individual compounds. Apart from this, a series of characteristics of HAs and whole soils (e.g. aromaticity, respiratory activity, extent of lignin alteration…) could be predicted with a variable success, not requiring previous interpretation of the mass spectra or integration of chromatographic peaks. The PLS-VIP plots in approach (iii) with the same format of a typical mass spectra lead to conclusions similar to MDS (used for variables ordination) or simple and multiple regressions, and illustrate the ion patterns relevant as regards to predicting soil and HA characteristics.
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Research Interests: Earth Sciences, Environmental Science, Geology, Organic Geochemistry, Pyrolysis, and 15 moreEnvironmental Chemistry, Features, Environmental Sciences, Litter, Sediment, Vegetation, CHEMICAL SCIENCES, Humus, Total Organic Carbon, Signature, Humic Acids, Chemical Composition, Organic Matter, Mine Soils, and Soil Water
A series of structural features of the three main humic fractions (humic acid, fulvic acid and humin) from different depths of a peat bog deposit in Mazagón (Huelva, Southern Spain) were isolated and analysed by flash pyrolysis–gas... more
A series of structural features of the three main humic fractions (humic acid, fulvic acid and humin) from different depths of a peat bog deposit in Mazagón (Huelva, Southern Spain) were isolated and analysed by flash pyrolysis–gas chromatography–mass spectrometry, solid-state 13C-nuclear magnetic resonance and Fourier transformed infrared spectroscopy. Such techniques demonstrate that the various humic fractions were very different not
Research Interests: Chemical Engineering, Chemistry, Analytical Chemistry, Nuclear Magnetic Resonance, Pyrolysis, and 15 moreDiagenesis, Peat, Analytical, Humic acid, Fulvic acid, Lignin, Humus, Fourier transform infrared spectroscopy, Infrared spectra, Molecular weight, Humic Acids, FT IR, Peat Bog, Humin, and Fulvic acids
This study comprises an innovative approach based on the combination of chromatography (analytical pyrolysis and pyrolysis compound-specific isotope analysis (Py-CSIA)), light stable isotopes, microscopy and mineralogy analyses to... more
This study comprises an innovative approach based on the combination of chromatography (analytical pyrolysis and pyrolysis compound-specific isotope analysis (Py-CSIA)), light stable isotopes, microscopy and mineralogy analyses to characterize the internal layering of coralloid speleothems from the Ana Heva lava tube in Easter Island (Chile). This multidisciplinary proxy showed that the speleothems consist of banded siliceous materials of low crystallinity with different mineralogical compositions and a significant contribution of organic carbon. Opal-A constitutes the outermost grey layer of the coralloids, whereas calcite and amorphous Mg hydrate silicate are the major components of the inner whitish and honey-brown layers, respectively. The differences found in the mineralogical, elemental, molecular and isotopic composition of these distinct coloured layers are related to environmental changes during speleothem development. Stable isotopes and analytical pyrolysis suggested alte...
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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... more
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...
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The application of biochar as an organic amendment in polluted soils can facilitate their recovery by reducing the availability of contaminants. In the present work, the effect of biochar application to acid soils contaminated by heavy... more
The application of biochar as an organic amendment in polluted soils can facilitate their recovery by reducing the availability of contaminants. In the present work, the effect of biochar application to acid soils contaminated by heavy metal spillage is studied to assess its effect on the quantity and composition of soil organic matter (SOM), with special attention given to soil humic acids (HAs). This effect is poorly known and of great importance, as HA is one of the most active components of SOM. The field experiment was carried out in 12 field plots of fluvisols, with moderate and high contamination by trace elements (called MAS and AS, respectively), that are located in the Guadiamar Green Corridor (SW Spain), which were amended with 8 Mg·ha−1 of olive pit biochar (OB) and rice husk biochar (RB). The results indicate that 22 months after biochar application, a noticeable increase in soil water holding capacity, total organic carbon content, and soil pH were observed. The amount...
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21 paginas, graficos, tablas, fotografias.-- Comunicacion oral presentada en las 13 Jornadas de Analisis Instrumental, celebradas del 14-16 de noviembre 2011, en Barcelona, Espana.
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2 pages, 1 figure, 2 references.-- Poster presentado al citado congreso en la Sesion 1: Archeology (A) No 571.-- Book of Abstracts of the Communications presented to the 26th International Meeting on Organic Geochemistry (IMOG), held in... more
2 pages, 1 figure, 2 references.-- Poster presentado al citado congreso en la Sesion 1: Archeology (A) No 571.-- Book of Abstracts of the Communications presented to the 26th International Meeting on Organic Geochemistry (IMOG), held in Costa Adeje, Tenerife – Spain, September 15 – 20, 2013.
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Poster presentado en EGU 2019, Viena (Austria) 7 al 12 de abril de 2019. Puede ver el Abstract en https://meetingorganizer.copernicus.org/EGU2019/EGU2019-17244.pdf
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Analytical pyrolysis is a tool widely used for investigating the nature of macromolecules. This technique has been applied with success for solving the chemical structure of geo- and biopolymers. However, with complex macromolecules, such... more
Analytical pyrolysis is a tool widely used for investigating the nature of macromolecules. This technique has been applied with success for solving the chemical structure of geo- and biopolymers. However, with complex macromolecules, such as fungal melanins, analytical pyrolysis presents some drawbacks due to the fact that they rarely can be obtained in a pure grade and contains a mixture of polysaccharides, chitin, proteins, nucleic acids, and lipids, among other materials. Analytical pyrolysis permits the characterization of the compounds co-extracted or linked to the melanin. Nevertheless, our data revealed that under the conditions usually employed in the pyrolysis of melanins, the technique presented serious limitations due to the complex structure and diversity of components that suffer extensive thermal degradation through secondary reactions with the production of considerable number of artifacts. To the light of pyrolysis data, the melanin of Ochroconis spp. is not based on...
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Research Interests: Chemistry and Soil Water
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Although combustion ashes are usually used in soils, little attention is paid to the CO sequestration potential of this practice. The present study aims to quantify carbon sequestration as carbonate compounds in a tailored synthetic... more
Although combustion ashes are usually used in soils, little attention is paid to the CO sequestration potential of this practice. The present study aims to quantify carbon sequestration as carbonate compounds in a tailored synthetic calcareous soil treated with biomass ash from a gasification power plant that uses olive cake. It is estimated that after ash amendment, 14.5g CO remained fixed per kg of fly biomass ash, 16.5g CO per kg of bottom biomass ash with plant cultivation and 19.7g CO per kg of bottom biomass ash without plant cultivation. This inorganic C fixation plus the organic (black) C contained in the ashes made the reutilization of ashes as K fertilizer a relevant practice due to its C resilience and rate, with a yearly C sequestering potential of ca. 8% of 'Soil carbon 4 per mille' goal, an initiative launched at the COP21.
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Among the most suitable techniques for the direct study of complex organic matrices such is soil organic matter (SOM) is analytical pyrolysis. The technique consists of a thermolytic degradation of macromolecules into small fragments that... more
Among the most suitable techniques for the direct study of complex organic matrices such is soil organic matter (SOM) is analytical pyrolysis. The technique consists of a thermolytic degradation of macromolecules into small fragments that may be separated and identified by gas chromatography–mass spectrometry (Py-GC/MS). In addition, recently the technique has been effectively hyphenated with other detection devices like isotope ratio mass spectrometry (IRMS) that will provide additional information relevant for the monitoring of biogeochemical processes including tracing the origin and dynamics of SOM pools. This study focused on the chemical characterization of the organic matter present in a soil sample under different kind vegetation cover from a Mediterranean climate (Andalusia, South western Spain), for it using techniques of analytical pyrolysis, with this techniques, we could find that organic matter consists mainly of alkanes / alkenes, fatty acids, aromatic, lignin, steran...
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Pyrolysis-compound specific isotopic analysis (Py-CSIA: Py-GC-(FID)-C-IRMS) is a relatively novel technique that allows on-line quantitation of stable isotope proportions in chromatographically separated products released by pyrolysis.... more
Pyrolysis-compound specific isotopic analysis (Py-CSIA: Py-GC-(FID)-C-IRMS) is a relatively novel technique that allows on-line quantitation of stable isotope proportions in chromatographically separated products released by pyrolysis. Validation of Py-CSIA technique is compulsory for molecular traceability in basic and applied research. In this work, commercial sucrose from C4- (sugarcane) and C3- (sugar beet) photosystem plants and admixtures, were studied using analytical pyrolysis (Py-GC/MS), bulk δ(13) C IRMS and δ(13) C Py-CSIA. Major pyrolysis compounds were furfural (F), furfural-5-hydroxymethyl (HMF) and levoglucosan (LV). Bulk and main pyrolysis compound δ(13) C (‰) were dependent on plant origin: C3 (F: -24.65 ± 0.89; HMF: -22.07 ± 0.41 ‰; LV: -21.74 ± 0.17 ‰.) and C4 (F: -14.35 ± 0.89 ‰; HMF: -11.22 ± 0.54 ‰; LV -11.44 ± 1.26 ‰). Significant regressions were obtained for δ(13) C of bulk and pyrolysis compounds in C3- and C4 admixtures. Furfural (F) was found (13) C deple...
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Research Interests: Earth Sciences, Environmental Science, Organic Geochemistry, Nuclear Magnetic Resonance, Forest fire, and 13 moreEnvironmental Sciences, Negative Affect, Organic, Wildfire, Environmental Impact, CHEMICAL SCIENCES, Fatty Acid, Gas Chromatography/mass Spectrometry, Mediterranean Basin, Organic Matter, Soil Water, Chemical Modification, and Biogeochemical Cycle
Research Interests: Western Europe, Exotic Species, Biology, Biological Sciences, Environmental Sciences, and 15 moreRhododendron, Long Chain Fatty Acid, Soil organic matter, Epicuticular Wax, Oak, CHEMICAL SCIENCES, Soil lipids, Taraxerol, Quercus canariensis, Ericaceae, Fatty Acid, Chemical Composition, Sterols, Organic Matter, and Bioactive Compound
Research Interests: Environmental Science, Biological Sciences, Environmental Sciences, Heavy Metal Pollution, Estuaries, and 12 moreHeavy Metal, Principal Components Analysis, Sediment, CHEMICAL SCIENCES, Environmental quality, Estuary, Total Organic Carbon, Component Analysis, Organic carbon, Industrial wastes, Shore, and Environmental
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Book in two volumes.-- Printed books are available at IRNAS-CSIC Library Avda. Reina Mercedes 10, 41012 Seville.-- Book of Abstracts of the Communications presented to the 26th International Meeting on Organic Geochemistry (IMOG), held in... more
Book in two volumes.-- Printed books are available at IRNAS-CSIC Library Avda. Reina Mercedes 10, 41012 Seville.-- Book of Abstracts of the Communications presented to the 26th International Meeting on Organic Geochemistry (IMOG), held in Costa Adeje, Tenerife – Spain, September 15 – 20, 2013.The IMOG is the official conference of the European Association of Organic Geochemists (EAOG) and one of the most important events on this subject in the world. After the previous IMOG meetings in Madrid (7th IMOG; 1975), San Sebastian (17th IMOG; 1995), Seville (22nd IMOG), Tenerife is proud to host the fourth IMOG edition in Spain during September 15-20, 2013. We would like to dedicate this IMOG edition to Prof. Dr. Geoffrey EGLINTON. In the early 60’, together with Dick HAMILTON and the local Prof. Antonio GONZÁLEZ-GONZÁLEZ (1917- 2002), Prof EGLINTON developed the biomarker proxi in organic geochemistry when analysing leaf waxes of Canarian endemic Crassulaceae species (see communication OP...
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Forest fires exert changes in soil organic matter quality and quantity mainly in the organic top soil and first centimetres in the mineral horizon. These effects are highly variable and among other factors depend on fire and soil... more
Forest fires exert changes in soil organic matter quality and quantity mainly in the organic top soil and first centimetres in the mineral horizon. These effects are highly variable and among other factors depend on fire and soil characteristics. In this work the changes caused by fire to the soil organic matter in a gypseous soil (Hypergypsic Gypsisol). Undisturbed soil blocks were sampled in the field and burned in the laboratory. The burning treatment finished when the temperature reached 250 °C at 1cm depth in the Ah-horizon. In the burned blocks a decrease in soil organic carbon (CO) was observed in the soil O horizon (75%) and down till the 1st cm in the mineral Ah horizon. Under the conditions of our burning experiment no appreciable neat differences were observed in the inorganic C content (CI). Soil organic matter alteration caused by fire was assessed at a molecular level using direct analytical pyrolysis (Py-GC/MS). Fire severely modified soil organic matter molecular str...