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Póster presentado en la sesión S07.01-P.: Soil organic matter from bulk to molecular scales: innovative methods and applications.-- Congreso celebrado del 2-6 de julio 2012, en Fiera del Levante, Bari, Italia., Wildfires convert large amounts of biomass to CO2, but concomitantly alter soil C pools. Biomass burning causes changes in the lipid pattern, and the composition of aliphatic and aromatic hydrocarbons of fire-affected recent and fossil soils offers specific fingerprint indicators for diagnosis of vegetation burning and burning conditions.

Póster 230 presentado en la Session 2: Soil and peat and terrestrial OM 1.-- Congreso celebrado del 18-23, en septiembre de 2011, en Interlaken, Austria., Piçarras (a vernacular term for podzols) occur along the South Eastern costal zone of Brazil between Rio Grande do Sul and Rio de Janeiro States. Piçarras are formed as a result of cemenentation of the soil B horizon formed on mostly sandy littoral barrier sediments covered by the lush Atlantic forest. The cementing material is composed by the mixture of sesquioxides (2-4%) and humic material exhibiting the elemental C content between 1 and 3%, calculated per dry weight of the sediment. It is assumed that the colonization of the accreted littoral bodies by vegetation occurred rapidly and contributed to the accumulation of humic material. Our study was carried out along a 3 km trench profile, perpendicular to the shore line in Volta Velha which is a private biological reserve area situated in the municipal district of Itapoá, in the northeast of Santa Catarina State, and is part of the area considered as the Atlantic Forest Biosphere Reserve. The investigated trench profile is also roughly perpendicular to the front of prograding Holocene barriers composed of fine to medium sand weekly cemented by humic material and sesquioxides produced by the weathering of heavy minerals. 14 samples were collected from the studied transect and submitted to inorganic, and organic elemental analyses, lipid extract GC-MS determination based on flash pyrolisis and 13C nuclear magnetic resonance (NMR) characterisation of organic matter, which was further dated by 14C AMS method.

3 pages, 2 tables, 11 references.-- FUEGORED 2010.-- Jornadas Internacionales celebradas del 6-10 de octubre 2010, en Santiago de Compostela, España.

4 páginas, 2 figuras, 8 referencias.-- FUEGORED 2010.-- Jornadas Internacionales celebradas del 6-10 de octubre 2010, en Santiago de Compostela, España., The Mediterranean region is prone to frequent forest fires. To elucidate the impact of fires on environmentally relevant physical and chemical properties of the soil as well as on the chemical composition of soil organic matter an ad-hoc experiment was designed. Representative soils from Central Spain under forest (O horizon, Lithic Leptosols under Quercus ilex and Pinus pinaster) and agricultural soil (Ap horizon, Luvisol) were thermally treated; whole sol samples were isothermal heated in an electric furnace at 350 °C in three time steps up to 600 s.

2 pages.-- Póster presentado en la Session: Geochemistry, del citado congreso celebrado en Sevilla y Cortegana (Huelva) del 4-6 de noviembre, 2009., Proyecto CGL 2006-12730-C03-02 (CICYT).

Póster presentado en the Workshop of the Spanish Society of Mass Spectrometry: VII Scientific Meeting of the Spanish Society of Chromatography and related techniques 16-19 octubre (2007) Granada, Coastal/estuarine environments are sensitive areas of great environmental and socio-economic concern in terms of ecosystem preservation and sustainable management. The significant continental input occurring in these areas is the main source of the broad spectrum of organic materials, including pollutants, introduced in the marine environment Due to the rapid accumulation and isolation of organic materials from biological degradations estuarine zones are good environments for studying the origins, pathway and fates of SOM. In particular the study of the lipid fraction at a molecular level, can contribute in a significant manner to a better delineation of the multistage geochemical processes that occur in estuarine sediments. The biomarker assemblages found in the Lipid fraction of SOM may also provide valuable information about the structure of the trophic system involved in the formation of the original organic fraction and some are used to trace specific biogenic sources. The main goal of this research was lo determine whereas the shifts observed to the lipid assemblage isolated from selected estuarine sediments collected from the Southwest Atlantic Coast of Spain, were informative about the origin of the organic mather and to the possible relationship with climatic and environmental events that occurred in the area in recent times. Few variations were observed in the patterns of the most abundant alkyl series (n-alkanes, n-fatty acids, n-alkanols and n-2-alkanones). In general, our findings are indicative of the existence of a complex input of organic matter (OM) lo the estuarine areas studied, mainly from terrestrial origin Temporal variations could also be attributed to terrigenous contributions after flooding from rivers, although different degradation rate of individual biomarkers as well as that of OM from different origins should not be neglected when interpreting biomarker assemblages in these geodynamically active environments. The variability observed in the biomarker distribution in sediments from estuary samples provides a good indicator of differences to the supply of terrigenous and marine OM. It is suggested that OM inputs fundamentally derived from soil erosion and the deposition of continental OM. The exposure of sediment layers lo periods with oxic conditions may also exert a selective degradation of the more labile planktonic marine OM.

Póster presentado en the Workshop of the Spanish Society of Mass Spectrometry: VII Scientific Meeting of the Spanish Society of Chromatography and related techniques 16-19 octubre (2007) Granada, Analysis of pyrolysis (Py) products by gas chromatography-mass spectrometry (GCMS) enables insight into the molecular structure of polymers and natural macromolecules. In general terms, most of pyrolytic fragments are diagnostic compounds in which the structure of the main building blocks is preserved. The technique has been also found suitable lo direct characterize complex environmental matrices, such as compost, biomass, soils and sediments. The thermolytie behavior of these materials primarily depends of the chemical composition of their pyrolizable organic moieties, and also on specific pyrolysis conditions (e.g. temperature, heating rate, particle size, etc.). Nowadays, the search of the best mild pyrolytic conditions lo analyse complex materials which could prevent the biased information derived from the appearance of secondary rearrangement products or degradation products at high temperature is considered a key point of analytical research. Recently, the double-shot pyrolysis technique which combines thermal desorption with conventional pyrolysis in combination with gas chromatography and mass spectrometry is acquiring high importance for the analysis of complex molecules. The present study deals with the thermal degradation behavior of complex environmental matrices using sub-pyrolysis temperatures, double-shot pyrolysis and flash pyrolysis. Materials analysed included Brazilian Oxisols under different vegetation covers, forest fire affected soils and marine sediments. To investigate the thermal released products of these matrices different pyrolysis experiments were performed: a gradient of sub-pyrolysis temperatures (200, 250, 300 and 350 ºC), double-shot pyrolysis at 450 or 500 ºC after a pre-pyrolysis step at 250 'C and straight flash pyrolysis at 500 ºC.

Congreso celebrado del 15 -20 de abril, 2007, en Viena, Austria.

José M. de la Rosa et al.-- 2 pages, 13 references.-- Póster SSS24-1MO5P-0442, presentado en la sesión Poster Programme - SSS24 Soil organic matter – cycling of elements and characterization of stable C pool(s) (co-listed in BG).-- Congreso celebrado del 2 - 7 de abril, 2006, en Viena, Austria., Nitrogen occurring in sedimentary organic matter (SOM) mainly derives from living organisms. Proteins and peptides, the most abundant nitrogen containing substances in SOM, have been traditionally considered as part of the labile fraction in the environment. On the other hand, recent studies have shown that proteinaceous material can resist microbial degradation in sedimentary environments and consequently a portion of the nitrogen is incorporated into biologically refractory organic material and removed from the active nitrogen pool (Knicker et al, 1996, Pantoja and Lee, 1999; Nguyen and Harvey, 2001; Knicker and Hatcher, 1997, 2001; Zang et al, 2001)., Nitrogen occurring in sedimentary organic matter (SOM) mainly derives from living organisms. Proteins and peptides, the most abundant nitrogen containing substances in SOM, have been traditionally considered as part of the labile fraction in the environment. On the other hand, recent studies have shown that proteinaceous material can resist microbial degradation in sedimentary environments and consequently a portion of the nitrogen is incorporated into biologically refractory organic material and removed from the active nitrogen pool.

Comunicación oral. Jornadas celebradas del 10 al 12 de noviembre, 1999, Barcelona., One of the most obscure points in the biogeochemical cycle of productive systems is the structural transfomations of N-forms in organic fertilizers and soil humic substances (humic acids, fulvic acids and humins). In fact, wet chemical analyses leaves up to 50% of the total N in compost and soil organic matter unidentified. This important methodological gap greatly limits the accurate molecular characterization of the N balance which is required for an efficient use of N from organic wastes and soil organic matter. The use of '5N as tracer isotope is the only way to monitor that balance since it allows continuous monitoring of exogenous N-forms incorporated to native organic matter pre-existent in soil. In this work we have intended to identify the N-compounds in compost and soil through the following experimental approach: i) 15N labelling fresh organic matter by incubation of a '5N-enriched mixture of city refuse compost (30%), wheat straw (64%) and 15NO3K (6%) for 80 days. The starting C/N ratio of the mixture was set to 20, where just 50% of the N was as 15N, ii) the labelled compost (1.6 g) was added to a soil free of organic matter (50 g), the moisture was adjusted to 66% of the water holding capacity and the mixture was incubated at 25 °C during 80 days, iii) by using standard laboratory procedures, both compost and soil were divided into different organic fractions: (a) water soluble, (b) alkali-soluble, acid-insoluble (humic acids), (c) acid-and alkali-soluble (fulvic acids) and (d) insoluble extraction residue (humin). In the case of the soil, a light material (free organic matter (e), of a density

Different classes of lipidic components have been isolated from a contaminated soil by CO under supercritical conditions. The extracts were analyzed by gas chromatography–mass spectrometry and compared with those obtained by Soxhlet extraction using two different solvent mixtures. The influence of pressure and temperature on the extraction efficiency were evaluated by using a rotatable central composite design. The method is useful for optimization of the extraction of the esters of fatty acids. However for fatty acids, an empirical approach was needed. Both methods, namely supercritical extraction and Soxhlet extraction give results which are in good agreement., The financial support of the Spanish Project CICYT PB95-0079 is greatly appreciated.

Póster 508.-- Simposio celebrado del 13 al 18 de septiembre, 1998, Roma.-- El libro consta de 224 páginas., For good management of the composting process it is essential to dispose of criteria to follow the progressive changes with time of chemical parameters in order to set the optimun composting endpoint. On the other hand, monitoring of changes in compost composition during the stabilization process is of key importance in assuring the quality of the final product for its agricultutal use. Among the well specified standards for compost the organic matter stability assume a particularly important role. To this stability made a decisive contribution the quantitative and qualitative characteristics of the lipidic fraction. In this work we have monitorized by GC-MS the chemical changes that undergoes the lipids isolated from city refuse wastes at discrete intervals in the course of the composting process. Three different lipidic fraction were studied: i) from free monomers, ii) from sterified monomers, and from high molecular weight lipidic macromolecules, the two later obtained after saponification of the extract and the non extractable residue. Some significative alterations were detected, such as the increase in the concentration of low molecular weight alkanoic acids among the free lipids. Likewise, clear differences were found among the lipidic components released after transesterification treatment of compost samples at different degree of maturation with F3B-methanol.

The application to soil of composts generated by biological recycling of organic wastes is a traditional practice required for the sustainable management of productive systems. Nevertheless, only a limited number of composts produced by current technologies offers the maturity degree suitable for improvement of agricultural soils. Among the well specified standards for compost quality, those related to organic matter stability assume a particularly important role. A proper piling and composting time of the wastes can be sufficient to ensure biological stability. However for good management of the composting process it is essential to dispose of criteria to assess the evolution with time of chemical parameters in order to set the optimum composting time from an economical viewpoint. Although simple biological tests have been used to define compost maturity, they do not yield relevant information as regards economy in a process in which mechanical rotation and temperature control during the whole composting time are of capital importance in rentabilizing an industrial production system. Therefore new criteria based exclusively in simple and reproducible analytical techniques are required. In this work we have recorded the chemical changes of different organic fractions isolated from urban refuse wastes at discrete intervals in the course of the composting process. We have examined the water soluble fraction, the lipid fraction and the humic acid-like fraction by spectroscopic (DC-NMR and FT-IR) and chromatographic techniques (GC/MS and Py-GC/MS). Sampling have been performed at different seasons for two years. From a structural viewpoint, some significant chemical changes were detected in the composition of lipid fractions, but the most striking observation was the detection by Py-GC/MS of increasing degree of aromatization in the humic acid-like fraction isolated from compost samples collected at the advanced transformation stages.

6 pages, 3 figures, 1 table, 23 references., The mechanism of the high-temperature hydrolysis and alkylation with tetraalkylammonium hydroxides of bio- and geopolymers has been approached mainly by studying the behaviour of single standard compounds. In the present work, we have applied this technique to three polymers of known structure, i.e. suberin, polycitraconic acid (PCA) and a lignin dehydrogenase polymer (DHP), related respectively to natural polyesters, fulvic acids and lignins, in order to get new insight into the reaction mechanism. As further application of the technique, the case study of the lignin signature during the coalification process has been analyzed by pyrolysis-butylation of humic acids extracted from two peat and lignite samples.

Instituto de Recursos Naturales y Agrobiología de Sevilla, C.S.I.C., P.O. Box 1052, 41080 Seville, Spain; E-mail address: delrio@irnase.csic.es (J.C. del Río), Molecular characterization of kerogen and asphaltene fractions isolated from three oil shales taken from the Puertollano deposit has been carried out by pyrolysis-methylation. Long-chain n-alkanes, n-alk-I-enes, long-chain carboxylic acid methyl esters and aromatic compounds were the major thermal degradation products obtained for both kerogen and asphaltene fractions. Different monomeric and dimeric lignin-derived compounds were also released. The use of pyrolysis-methylation provides additional information about the chemical structural composition of the macromolecular organic matter comprising kerogens and asphaltenes at a molecular level, to that gained from conventional pyrolysis. The chemical structures of the released products indicate that considerable amounts of functionalized compounds are bound to the macromolecular structure of asphaltenes and kerogens via ester and ether linkages., We wish to thank the Comisión Interministerial de Ciencia y Tecnología (CICyT) for providing financial support (project PB91-0074), and Professor H.-D. Liidemann for recording NMR data.

6 pages, 3 figures, 1 table, 16 references.-- Instituto de Recursos Naturales y Agrobiología, C.S.I.C.-- P.O.box 1052, 41080-Sevilla, Spain., Land treatment with high loading rates of olive oil mill effluents (alpechin) results in the quantitative increase of the lipidic fraction of the soil upper layer and in significative alterations in the lipid compositions of both the soil upper layer and the subsoil. GC-MS analysis of the lipidic fractions before and after the treatments showed the preferential accumulation of some hydrophobic components of the wastewater. These compounds were also retained by the humic acid (HA) fractions as seen by Pyrolysis-GC-MS., This work was supported by the CICYT of Spain (Project PB91-0034).

9 páginas, 1 figuras, 2 tablas, 21 referencias., Humic Acids (HAS) extracted from soils of very different origin have been analyzed by pyrolysis in the presence of tetramethylammonium hydroxide. The thermal degradation products consisted mainly of aliphatic series such as fatty acids methyl esters and a,w-methoxy fatty acid methyl esters. Triterpenoid compounds with ursane, oleanane and hopane skeletons were also detected in several samples. Aromatic units derived from lignin moieties were also detected although in minor amounts and corresponded mainly to guaiacyl and syringyl units. This procedure seems to release the more labile. aliphatic moieties attached to the aromatic nuclei of the HA structure.

Instituto de Recursos Naturales y Agrobiologia de Sevilla, C.S.I.C., P.O. Box 1052, 41080-Seville, Spain; E-mail address: delrio@irnase.csic.es, Humic acid (HA) fractions isolated from a peat and lignite deposit were studied by CP/MAS 13C-NMR and pyrolysis-methylation. Loss of carbohydrates, removal of methoxyls and formation of catechols during the coalification process was evident. Pyrolysis-methylation released a great variety of components, the lignin-derived monomers being the most prominent. A very striking feature was the release of benzenecarboxylic moieties after pyrolysis-methylation which have not been observed previously by pyrolytic techniques. These moieties were released in higher amounts from the lignite HA, suggesting that the content in carboxylic groups increase with coalification, at least up to the lignite stage. Oxidation of the C-3 side chain of the lignin structure would produce these benzenecarboxylic acids and benzylic ketones., We wish to thank the Comision Interministerial de Ciencia y Tecnologia (CICyT) for providing financial support (Project PB91-0074) and Professor H.-D. Lüdemann for recording NMR spectra.

10 páginas, 4 figuras, 3 tablas, 16 referencias. Institute de Recursos Naturales y Agrobiologia, C.S.I.C., P.O. Box 1052, 41080-Sevilla, (Spain), Pyrograms of three fulvic acids (FAs) of different origins and the corresponding pyrograms obtained by reactive pyrolysis with tetramethylammonium hydroxide (TMAH) are compared. This procedure introduces both striking qualitative and quantitative changes in the pyrolytic patterns of the FAs, which are discussed in terms of the usefulness of this approach to structural studies. Some non-pyrolysis compounds (probably retained in the macromolecular fulvic matrix) seem to be released when the FAs are pyrolysed in the presence of TMAH. A set of benzenecarboxylic acid standards was also pyrolysed both in the absence and in the presence of TMAH. The results obtained suggest a thermally assisted chemolysis rather than in situ methylation of the pyrolysis products.

4 pages, 2 figures, 1 table, 3 references., Oil shales have a special geochemical interest both as source rocks and as an energy resource in themselves. In fact, many outstanding works on the application of biomarkers for source rocks-oil correlations have been carried out in these sedimentary rocks.

8 páginas, 1 figura, 2 tablas. EFCE Publicación Series nº 68. Proceedings del VII Congreso Nacional de Química: Química Agrícola y Alimentaria-2. Sevilla 12-17 de octubre de 1987., Seasonal variations of agrochemical parameters and the nature of free organic compounds in anaerobic sewage sludges were analysed. Some limitations to the land application of these sludges could arise from their high contents in free hydrophobic substances. Most of the identified compounds in ether and toluene extracts (more than 20% of sludge dry weight) were series of fatty acids and their esters. Dialkyl phthalates and alkylbenzenes derived from industrial inputs were also frequent.

4 páginas, 2 figuras, 1 tabla, 25 referencias., [ES]: El anáalisis de la fracción resina del lignito de Puentes de García Rodríguez rvela la presencia de compuestos isoprenoides de diversa naturaleza, ácidos grasos e hidrocarburos. Se proponen vías de formación de los terpenos aislados y se comprueba que este lignito es un sedimento en fase de diagénesis intermedia., [EN]: The analysis of this resin from the Puentes de García Rodríguez lignite reveais the existence of isoprenoid compounds of different nature, fatty acids and hydrocarbons. Ways and means of development of isolated terpenes are proposed, and it is verified that this lignite is a sediment in a phase on intermediate diagenesis.

10 pages, 3 figures, 26 references.-- Conferencia presentada al 13 Simposio Internazionale di Agrochimica, celebrado del 8-11, octubre, 1984, en Pisa, Italia., [EN]: In this communication the results of a study about: the amounts and types of lipid organic componen:s extracted from a municipal refuse compost, as well as the quantitative and qualitative effects upon the soil lipid fraction resulting from its periodic application are reported. A sligth increase of the total lipid contents in the compost-amended soil was detected, which results in a certain accumulation of both n-alkanes and fatty acids fractions bounded to the organic-mineral soil complex., [IT]: In questo lavoro si studia la quantità ed i tipi di lipidi estratti da un compost di rifiuti solidi urbani come pure gli effetti qualitativi sulla frazione lipidica del suolo, quando essi sono applicati sul terreno. Nel suolo trattato si osserva un piccolo aumento del contenuto totale di lipidi che si osserva in modo particolare nelle frazioni degli n-alcani e degli acidi grassi legati al complesso organo-minerale.

6 páginas, 3 figuras, 1 tabla, 17 referencias. Comunicación presentada ante el citado Congreso que tuvo lugar en Sevilla, del 26 al 30 de septiembre de 1988. Publicada en la Sección II: Química de Suelos. Otras comunicaciones presentadas por el IRNAS: http://hdl.handle.net/10261/47681. http://hdl.handle.net/10261/37273. http://hdl.handle.net/10261/37029. http://hdl.handle.net/10261/54668., En los últimos años ha crecido el interés por el estudio de la fracción lipídica del suelo, debido a la reconocida influencia de la misma sobre propiedades físicas y bioquímicas del suelo directamente relacionadas con su fertilidad (Jambu et al.,1979; Stevenson,l982). El status de dicha fracción puede verse modificado por el aporte al suelo de composts procedentes de residuos sólidos urbanos, ya que estos materiales contienen proporciones notables de materia orgánica no estabilizada de tipo hidrofóbico (Inoko et al., 1979; González-Vila et al., 1982) susceptible de acumularse en el suelo en condiciones edafoclimáticas y biológicas desfavorables (Kaufman y Horwick, 1983). Esta acumulación puede afectar a procesos de descomposición de material carbonoso e inmovilización de N inorgánico, como ha podido comprobarse para el caso de la aplicación de lodos de depuradora (Beaucham et al., 1979; Terry et al., 1981).

9 páginas, 4 tablas y 12 referencias. Trabajo presentado en el III Congreso Nacional de Química. Sevilla (España). Sevilla, 20-22, Febrero, 1980. Vol. 1: Química agrícola., The results from the analysis of organic and mineral fractions of three Andalusian composts are discussed. These materials have high contents of organic matter and satisfactorily low contents of potentially toxic non essential elements. However, the excessive levels of some essential micronutrients may be toxic to plants. It is suggested that the data from chemical analysis must be correlated with field experiments before heavy applications of compost to agricultural land.