Effect of Ph and vegetation cover in soil organic matter structure at a high-mountain ecosystem (Sierra Nevada National Park, Granada, Spain)

Poster nº 8246 en EGU General Assembly 2020, Online, 4–8 May 2020During the last decade, soil organic matter dynamics and its determining factors have received increased attention, mainly due to the evident implication of these parameters in climate change understanding, predictions and possible management. High-mountain soil could be considered as hotspot of climate change dynamic since its high carbon accumulation and low organic matter degradation rates could be seriously altered by slight changes in temperature and rainfall regimes associated to climate change effects. In the particular case of Sierra Nevada National Park, this threat could be even stronger due to its Southern character, although its elevated biodiversity could shed some light on how could we predict and manage climate change in the future. In this study, a quantitative and qualitative organic matter characterization was performed and soil microbial activity measured to evaluate the implication of pH and vegetation in soil organic matter dynamics. The sampling areas were selected according to vegetation and soil pH; with distinct soil pH (area A with pH7) and vegetation (high-mountain shrubs and pine reforested area). Soil samples were collected under the influence of several plant species representatives of each vegetation series. Six samples were finally obtained (five replicates each); three were collected in area A under Juniperus communis ssp. Nana (ENE), Genista versicolor (PIO) and Pinus sylvestris (PSI) and other three were collected in area B under Juniperus Sabina (SAB), Astragalus nevadensis (AST) and Pinus sylvestris (PCA). Qualitative and quantitative analyses of soil organic matter were made to establish a possible relationship with microbial activity estimated by respiration rate (alkali trap) and fungi-to-bacteria ratio using a plate count method. Soil easily oxidizable organic carbon content was determined by the Walkley-Black method (SOC %) and organic matter amount was estimated by weight loss on ignition (LOI %). Analytical pyrolysis (Py-GC/MS) was used to analyse in detail the soil organic carbon composition. Our results showed that the microbial and therefore the dynamics of organic matter is influenced by both, soil pH and soil of organic matter. So that the pH in acidic media prevail as a determining factor of microbial growth over soil organic matter composition conditioned by vegetation.Ministerio de Ciencia Innovación y Universidades (MICIU) for INTERCARBON project (CGL2016-78937-R). N.T. Jiménez-Morillo and L. San Emeterio also thanks MICIU for funding FPI research grants (BES-2013-062573 and Ref. BES-2017-07968). Mrs Desiré Monis is acknowledged for technical assistance

Soil organic matter origin, dynamic and fate : A state-of-the-art research addressing Mediterranean agroecosystems main threats

Tesis doctoral para optar al grado de Doctora por la Universidad de SevillaSoils represent an essential natural, practically non-renewable resource that provides many critical ecosystem services necessary for life. Furthermore, soils play a critical role in maintaining the balance of the carbon cycle, acting as the largest terrestrial carbon pool which made them crucial in mitigating climate change. Understanding the complexity and dynamics of soils is, therefore, apart from preserving and managing this valuable natural resource, critical for the benefit of current and future generations. However, the changing climate and increasing intensity of agricultural production pose significant threats to the sustainability and role of soils, mainly by contributing to a depletion in soil organic matter (SOM) and altering its dynamics. Indeed, Mediterranean soils face these threats in a more severe way due to their geographic location, particular climate and inherent low content of SOM. It is critical to shedding light on this respect by combining different analytical procedures and providing complementary and valuable information on processes that regulate the accumulation, decomposition, and transformation of SOM. The main objective of this thesis was to investigate and deepen our knowledge about the two main threads affecting carbon dynamics in Mediterranean soils i.e., climate change and intensive agricultural practices. For this, advanced analytical techniques appropriate for the study of complex matrices such are soils were tested and combined to study SOM in two distinct and representative Mediterranean soils, in terms of extension and ecosystem relevance: Mediterranean savannahs, commonly known as “dehesas” (Section I) and agricultural soils (Section II).El presente trabajo se ha realizado en el marco del proyecto titulado “Intercambio y flujos de carbono en suelos de ecosistemas mediterráneos naturales y manejados (bosques, dehesas y cultivos” (INTERCARBON, CGL2016-78937-R), así como en colaboración activa con el proyecto titulado “Las dehesas frente al cambio global: una aproximación multi-funcional (DECAFUN, CGL2015-70123-R)”. Ambos proyectos han sido financiados por el Ministerio de Economía y Competitividad (MINECO), así como el contrato predoctoral de Layla Márquez San Emeterio dentro del proyecto INTERCARBON como parte del Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+I para la formación de doctores (FPI, BES-2017-07968). La Unión Europea ha colaborado con el aporte de fondos de cohesión (FEDER) a los anteriores proyectos y mediante los proyectos MAXRoot-C y MIXRoot-C. European Joint Programme EJP SOIL “Towards climate-smart sustainable management of agricultural soils” 2nd Internal Call topic: CM1 — Plant below-ground inputs to enhance soil carbon sequestration (Grant Agr. Nr. 862695).Peer reviewe

Análisis isotópico directo de compuestos específicos mediante pirólisis (PY-CSIA) de corteza y lignina: obtención de biomarcadores

16 diapositivas de la presentación en el Ciclo de conferencias predoctorales 2019 del IRNASN

Compound-specific isotopic analysis of fatty acids in three soil profiles to estimate organic matter turnover in agricultural soils.

9 páginas.- Presentación nº 18526 en EGU General Assembly 2020, Online, 4–8 May 2020Soil lipids encompass substances of mainly plant or microbial origin that are insoluble in water and soluble in organic solvents such as ether, hexane, benzene, chloroform or dichloromethane. This soil organic fraction is of great interest because it encompasses biomarkers associated to soil microbial communities, i.e. Gram positive/negative bacteria, mycorrhizae, actinomycetes, etc. and because of its transitory nature that provides insights into soil organic matter (SOM) dynamics and soil carbon turnover. Compound-specific isotope analysis (CSIA) have been used in biomarker studies to investigate the assimilation of carbon from external inputs into SOM. This study determined the distribution and d13C composition of fatty acids as dominant part of the soil lipid fraction to assess turnover times in agricultural practice. Soil samples were taken from three depth intervals (0-5, 5-20, 20-40 cm) from a Mediterranean agricultural soil at ¿La Hampa¿ experimental station used for a crop rotation experiment with wheat (C3 plant) and maize (C4 plant). Using the C4 biosynthetic pathway, maize discriminates less strongly against 13C, i.e. d13C values of fatty acids originating from maize are less negative than those of fatty acids from wheat. Soil lipids were extracted using a DCM:MeOH (3:1) solvent mixture. Fatty acids were transmethylated with MeOH:acetyl chloride (30:1) to form fatty acid methyl esters (FAMEs) while the hydroxy groups of hydroxy acids, alcohols, sterols and other compounds were silylated using BSTFA prior to analysis by gas-chromatography combustion chamber isotope ratio mass spectrometry (GC-C-IRMS) for carbon isotope ratios. Compounds were identified through their mass spectra by gas-chromatography mass spectrometry (GC-MS) and quantified by gas chromatography with flame ionization detection (GC-FID). Only two maize harvests after wheat cultivation, a significant 13C enrichment of up to 2 ¿ was found in the saturated C20, C22 and C23 FAMEs and the mono-unsaturated C22 FAME and of up to 5 ¿ in the leaf wax-derived C29 and C31 n-alkanes relative to the control treatments without maize input. No significant differences, however, were found for alcohols and hydroxy acids. These differences may respond to the high specificity of the long-chain n-alkanes from plant origin, whereas the other compounds FAMEs, and mainly alcohols and hydroxyl acids are less specific plant markers and may have a diverse origin. No significant differences in the isotopic composition were observed at different depths within treatments apart from a slight d13C enrichment of 1.5 ¿ in the upper soil layer (0-5 cm) in the maize plots relative to the deeper layers. It is worth noticing that SOM content remained very low (< 1.3%) over the entire duration of the experiment, with no significant differences despite the high amount of C4 biomass presumably added to the soil during the two growth periods. Together with the d13C enrichment observed in the maize plots, this points to high mineralization rates in these soils and implies both a rapid turnover of plant debris into the SOM.Ministerio de Ciencia Innovación y Universidades (MICIU) for INTERCARBON project (CGL2016-78937-R). L. San Emeterio also thanks MICIU for funding FPI research grants (BES-2017-07968). Mrs Desiré Monis is acknowledged for technical assistance

Recogida de datos de cuantificación de lípidos según familias de compuestos

Formato Excel con distintas hojas, cada una de ellas correspondiente a un grupo de compuestosPeer reviewe

Efecto del pH y la vegetación en la dinámica de la materia orgánica en suelos de alta montaña

4 páginas.- 3 figuras.- 2 tablas.- 3 referencias.- Póster presentado en el Congreso El suelo: clave para una gestión ambiental sostenible en un escenario de cambio global. IX Simposio sobre Control de la Degradación y Recuperación de Suelos CONDEGRES 2021, celebrado entre los días 24 y 25 de mayo de 2021Conocer mejor la dinámica de la materia orgánica del suelo se ha convertido en objetivo de numerosos estudios, ya que el suelo es uno de los mayores reservorios de carbono que existen. En concreto, este estudio preliminar, se centra en los suelos de alta montaña situados en Sierra Nevada (Granada) ya que la amenaza de pequeñas variaciones en el régimen de temperatura y humedad derivadas del cambio climático podrían conllevar a una liberación importante del carbono almacenado en ellos. Con objetivo de establecer la influencia del pH y la vegetación en la dinámica de la materia orgánica en este escenario, se recolectaron muestras de suelo de dos zonas cercanas, pero con diferencias en su litología, principalmente en relación a los valores de pH. Para cada zona se muestrearon suelos bajo una vegetación de matorral de alta montaña y área reforestada con pino albar. Se ha realizado una caracterización cualitativa y cuantitativa de la materia orgánica del suelo, estudiando de forma paralela la abundancia y actividad microbianas.N

Vegetation and pH implications on the dynamic of soil organic matter at high-mountain shrubs ecosystems from Sierra Nevada National Park (Granada, Spain)

Comunicación oral presentada en el ISMOM 2019 - 8th International Symposium on Interactions of Soil Minerals with Organic Components and Microorganisms: 23-28 june, Sevilla (Spain)During the last decade soil organic matter dynamic and its determining factors have received an increased attention mainly due to the evident implication of these parameters in climate change understanding predictions and possible management. High-mountain soil could be consider as hotspot of climate change dynamic since its high carbon accumulation and low organic matter degradation rates could be seriously altered by slight changes in temperature and rainfall regimens associated to climate change effects. In the particular case of Sierra Nevada National Park this threat could be even stronger due to its Southern character although its elevated biodiversity could shed some light on how could we predict and manage climate change in the future. In this study we selected different sampling areas with distinct soil pH (area A with pH7) and vegetation (high-mountain shrubs and pine reforested area). Soil samples were collected under the influence of several plant species representatives of each vegetation series. Six different kind of samples were finally obtained (five replicates each); three were collected in area A under Juniperus communis ssp. Nana (ENE) Genista versicolor (PIO) and Pinus sylvestris (PSI) and other three were collected in area B under Juniperus Sabina (SAB) Astragalus nevadensis (AST) and Pinus sylvestris (PCA). Quantitative and qualitative organic matter characterization and soil microbial biomass and activity were measure in order to evaluate the implication of soil pH and vegetation in soil organic dynamic at this particular high-mountain environment at Sierra Nevada National Par

Efecto del pH y la vegetación en la dinámica de la materia orgánica en suelos de alta montaña (Póster-Presentación oral)

Presentación oral del póster por Gael Bárcenas-Moreno en el IX Simposio sobre Control de la Degradación y Recuperación de Suelos CONDEGRES 2021, celebrado entre los días 24 y 25 de mayo de 2021.- enlace al video https://youtu.be/fVxmT6Mg7w8Peer reviewe

Influencia de la vegetación y el pH en la dinámica de la materia orgánica en suelos de alta montaña del P.N. de Sierra Nevada

Póster presentado en la XXXII Reunión Nacional de Suelos (RENS2019) 10-13 de septiembre de 2019 en SevillaDurante la última década, los factores relacionados con la dinámica de la materia orgánica del suelo han recibido gran atención debido, principalmente, a su implicación en la evolución del cambio climático, la predicción de sus efectos y posibles alternativas de gestión. Los suelos de alta montaña pueden considerarse puntos críticos ya que mantienen altas tasas de acumulación de carbono y bajas de degradación de materia orgánica, balance que podría alterarse por leves cambios en los regímenes de temperatura y precipitación asociados con el cambio climático. En el caso particular del Parque Nacional de Sierra Nevada, esta amenaza podría ser aún más marcada debido a su localización en el sur de Europa justo en el ecotono mediterráneo, dónde se refleja cualquier cambio ambiental de forma más temprana, aunque su elevada biodiversidad podría tener efectos regulatorios y arrojar alguna luz sobre cómo podríamos predecir y gestionar en el futuro los efectos del cambio climático. Para evaluar la implicación del pH y la vegetación sobre la dinámica de la materia orgánica del suelo, se seleccionaron dos áreas cercanas sobre diferente sustrato que condicionaban diferentes valores de pH: área A, sobre materiales ácidos y con pH 7. Para cada área se muestrearon suelos bajo una vegetación equivalente de arbustos de alta montaña y área reforestada de pino albar. Finalmente se obtuvieron seis tipos diferentes de muestras con cinco repeticiones cada una; tres fueron recolectados en el área A bajo Juniperus communis ssp. nana (ENE), Genista versicolor (PIO) y Pinus sylvestris (PSI) y otros tres se recolectaron en el área B bajo Juniperus sabina (SAB), Astragalus nevadensis (AST) y Pinus sylvestris (PCA). Se realizó una caracterización cuantitativa y cualitativa de la materia orgánica del suelo y se estudió su actividad microbiana. El estudio incluyó el análisis detallado de la estructura molecular mediante pirolisis analítica (Py-GC/MS). Los resultados se discutirán en relación con la influencia del sustrato y la vegetación sobre la dinámica de la materia orgánica del suelo y particularmente de la degradación de ligninas, en este entorno particular de alta montaña del Parque Nacional Sierra Nevada.Proyecto INTERCARBON (CGL2016-78937-R) cofinanciado con fondos de cohesión EU-FEDER. L.M.S.E. agradece su contrato FPI (BES-2017-07968). Desiré Monis por su asistencia técnicaN

Microplastic pollution in the atlantic ocean: identification of polymer types and additive content using analytical pyrolysis (PY-GC/MS)

Póster (P-EA-22) presentado en la XVIII Reunión de la Sociedad Española de Cromatografía y Técnicas Afines (SECyTA 2018), Granada, del 2 al 4 de Octubre de 2018.Plastic gradually fragments into smaller pieces forming microscopic fractions of less than 5 mm commonly known as microplastics. These microplastics have become one of the most persistent pollutants of the sea and beaches, due to their small size, their ubiquity and global distribution [1]. An estimated 80% of microplastics pollution comes from land, while about 18% of these marine debris is attributed to the fishing industry [2]. Moreover, previous studies reported up to 44% of raw pellets and values above 100g/l of sand in the coastal zones of the Canary Islands. The Canary Islands constitutes an area of accumulation of microplastics, being found this type of pollution even in beaches infrequently visited [3]. Microplastics represents a major threat to the environment due to the following reasons [4]: • Are typically hydrophobic with large surface areas and high adsorption capacity of POPs (Persistent Organic Pollutants) and PBTs (Persistent, Bioaccumulative and Toxic substances). • As they adsorb POPs, microplastics can result in a double-entry pollution vector: as a POPs vector and by the plastic itself. • High abundance and long residence time. • Absorption and ingestion by aquatic organisms and subsequent transfer to higher trophic evels. Given that microplastic is a relatively new environmental problem and their newly increased pollution levels, it is important to better understand their impact. The establishment of standardized analysis procedures for their chemical characterization is required among the scientific community. A total of 10 microplastic samples collected in the Canary Islands were optically characterized and analysed using pyrolysis-gas chromatography coupled to mass spectrometry (Py-GC/MS). The pyrolysis temperature was 400 ºC for 1 minute and the chromatographic conditions and compound assignment procedure are described elsewhere in [5]. The studied microplastics were mainly light polyolefins (polyethylene, PE and polypropylene, PP) but one that was found to be composed mainly of cellulose. Other compounds and additives associated with the microplastics, such as fatty acids, ketones and plasticizers (phthalates) were found with discriminant value to differentiate different polymers. Py-GC/MS was found an appropriate tool for microplastic research. In this work it was possible to identify the nature of all samples studied, elucidate they polymer composition if any and also provide valuable information about origin and production line.[1] Andrady, A.L. (2011). Microplastics in the marine environment. Mar. Pollut. Bull. 62: 1596―1605. [2] Rochman, C.M. (2018). Microplastics research—from sink to source. Science 360 (6384): 28―29. [3] Herrera, A., Asensio, M., Martínez, I., Santana, A., Packard, T., & Gómez, M. (2018). Microplastic and tar pollution on three Canary Islands beaches: an annual study. Mar. Pollut . Bull. 129: 494―502. [4] Anderson, J.C., Park, B.J., & Palace, V.P. (2016). Microplastics in aquatic environments: Implications for Canadian ecosystems. Environ. Pollut. 218: 269―280. [5] González-Pérez J.A., Jiménez-Morillo N.T., de La Rosa Arranz J.M., Almendros G., González-Vila F.J. (2015). Pyrolysis-gas chromatography-isotope ratio mass spectrometry of polyethylene. J. Chrom. A 1388: 236―243.Layla M. San Emeterio ‘Ministerio de Ciencia, Innovación y Universidades’ grant BES-2017-079811. Projects CGL2016-78937-R co-financed by FEDER Funds. Desiré Monis and Alba Carmona for technical assistance.Peer reviewe