Joeri Kaal

Holocene vegetation changes in NW Iberia revealed by anthracological and palynological records from a colluvial soil

Macroscopic charcoal, pollen and non-pollen palynomorphs were isolated from a colluvial soil located on a small hill in Campo Lameiro (NW Spain) in order to elucidate the vegetation history of the area and its relation to fire and human activities. The presence of macroscopic charcoal throughout the 2.10 m thick soil (42 samples) is evidence of frequent fires during the last c. 6300 years. The charcoal record was dominated by Quercus (probably Q. robur), Ericaceae (probably Arbutus unedo and Erica arborea) and Fabaceae (mainly Genista type). Abrupt changes in the charcoal assemblage are less explicit in the pollen sequence, probably as a result of pollen inflow from the downhill surroundings of the study site. Combined results indicated that the original oak woodland was gradually replaced by pyrophytic shrubs (Ericaceae and Fabaceae) as a result of fire recurrence. Non-pollen palynomorphs strongly suggested that vegetation was deliberately ignited by past human societies to facilitate grazing. No evidence of local agricultural practices was found. Episodes of accelerated shrubland expansion occurred c. 6000—5500 cal. BP, c. 4000—3500 cal. BP and c. 1700 cal. BP, the latter of which caused the definitive settlement of shrublands dominated by Ericaceae and Fabaceae which are nowadays widespread in NW Iberia.

Application of FTIR spectroscopy to the characterization of archeological wood.

Two archeological wood samples were studied by attenuated total reflectance Fourier transform infrared (FTIR-ATR) spectroscopy. They originate from a shipwreck in Ribadeo Bay in the northwest of Spain and from a beam wood of an old nave of the Cathedral of Segovia in the central Spain. Principal component analysis was applied to the transposed data matrix (samples as columns and spectral bands as rows) of 43 recorded spectra (18 in the shipwreck and 25 in the beam wood). The results showed differences between the two samples, with a larger proportion of carbohydrates and smaller proportion of lignin in the beam than in the shipwreck wood. Within the beam wood, lignin content was significantly lower in the recent than the old tree rings (P=0.005). These variations can be attributed to species differences between the two woods (oak and pine respectively), with a mixture of guaiacyl and syringyl in hardwood lignin, whereas softwood lignin consists almost exclusively of guaiacyl moieties. The influence of environmental conditions on the FTIR fingerprint was probably reflected by enhanced oxidation of lignin in aerated conditions (beam wood) and hydrolysis of carbohydrates in submerged-anoxic conditions (shipwreck wood). Molecular characterization by analytical pyrolysis of selected samples from each wood type confirmed the interpretation of the mechanisms behind the variability in wood composition obtained by the FTIR-ATR.

Soil Formation of “Atlantic Rankers” from NW Spain—A High Resolution Aluminium and Iron Fractionation Study

Abstract Atlantic rankers belong to the group of “cryptopodzolic rankers”, which are ubiquitous in the mountainous cool/temperate humid regions of Western Europe. The rankers of Galicia (NW Spain) formed by thousands of years of colluviation. The preponderance of Al-stabilised organic matter (OM) masks the horizonation and polycyclic character (i.e., stratification) of these soils. Cryptopodzolic rankers are generally thought to be the outcome of podzolisation. This soil type is part of the recent discussion on how to classify soils developed from nonvolcanic parent material having andic properties. To better understand the formation processes of these soils, the Al and Fe fractionation of four typical Atlantic rankers were studied by selective dissolution in acid NH 4 -oxalate, Na-pyrophosphate and the chlorides of K, La and Cu. A high-resolution sampling approach allowed us to investigate the soils in greater detail than simply sampling by horizon. The rankers studied display a distribution of Fe- and Al-OM complexes that is typical of cryptopodzolic soils. However, these organomineral associations were probably immobile due to the high Al saturation. We argue that the soils owe their characteristic chemical status to external factors rather than to translocation of organomineral associations: variations in Al-OM concentrations could be linked to changes in weathering/leaching intensity and colluviation rates caused by anthropogenic disturbances or changes in regional climate regime.

Molecular characteristics of permanganate- and dichromate-oxidation-resistant soil organic matter from a black-C-rich colluvial soil

Samples from a colluvial soil rich in pyrogenic material (black C, BC) in north-west Spain were subjected to K2Cr2O7 and KMnO4 oxidation and the residual soil organic matter (SOM) was NaOH-extracted and analysed using analytical pyrolysis–gas chromatography–mass spectroscopy (Py-GC/MS) and solid-state 13C cross-polarisation magic angle spinning–nuclear magnetic resonance (13C CP MAS-NMR) in order to study the susceptibility of different SOM fractions (fresh, degraded/microbial, BC and aliphatic) towards these oxidising agents. Untreated samples that were NaOH-extracted were also analysed. The Py-GC/MS and 13C NMR indicated that KMnO4 promotes the oxidation of carbohydrate products, mostly from degraded/microbial SOM and lignocellulose, causing a relative enrichment of aliphatic and aromatic structures. Residual SOM after K2Cr2O7 oxidation contained BC, N-containing BC and aliphatic structures. This was corroborated by a relatively intense resonance of aromatic C and some signal of alkyl C in 13C NMR spectra. These results confirm that dichromate oxidation residues contain a non-pyrogenic fraction mainly consisting of aliphatic structures.

Composición de la materia orgánica en los suelos de seis zonas edafoclimáticas del Magdalena (Colombia)

Los suelos al noreste del departamento del Magdalena (Colombia) afrontan una creciente degradacion, principalmente por las bajas tasas de acumulacion de materia organica del suelo (MOS) y su reducido periodo de transformacion. Tradicionalmente se han realizado estudios tendentes a mitigar esta situacion, pero todos se han centrado en aspectos cuantitativos analizando los contenidos totales de MOS. Por tanto, en el presente estudio se propuso determinar la composicion molecular de la MOS en suelos de seis zonas con diferentes caracteristicas edafoclimaticas en zonas de bosques humedos y secos tropicales, con una altitud entre 5-956 msnm, temperatura media entre 24-30 °C, precipitacion media entre 663-2000 mm y diferentes usos actuales (bosques y cultivos varios). Para ello se caracterizo por pirolisis (acoplada a cromatografia de gases y espectroscopia de masas) la MOS extraida con NaOH 0.1M de muestras superficiales en suelos cultivados y de bosques. Fueron cuantificados 110 productos de pirolisis en la siguiente proporcion: compuestos con N (34,1% ± 5,1%), polisacaridos (21,1% ± 7.1%), aromaticos (20,0% ± 4.5%), alifaticos (7,7%± 1,4%), fenoles (7,0% ± 5,0%), poliaromaticos (3,6% ± 0,9%), ligninas (0,3% ± 0,3%) y otros compuestos (0,2% ± 0,1%). A traves del analisis de varianza no se encontraron diferencias estadisticas entre los productos de pirolisis para usos del suelo (bosque y cultivados), pero si para las zonas muestreadas. Por otro lado el analisis factorial por componentes principales permitio reducir el conjunto de compuestos productos de pirolisis en dos variables sinteticas que explicaron el 51% de la variabilidad total. Aunque en todas las zonas se evidencio una MOS con un grado importante de descomposicion, el factor 1 permitio separar entre MOS de origen microbiano relativamente descompuesta y MOS fresca o de descomposicion lenta y de origen vegetal. En terminos generales, las zonas con mayor pluviosidad y menores promedios de temperatura mostraron una contribucion relativamente alta de MOS microbiana y, en menor proporcion, de MOS de origen vegetal tanto para suelos de bosques como para suelos de cultivo, en contraste con las zonas mas secas que presentaron mayor proporcion de MOS de origen vegetal.

Reconstructing Holocene evolution in the archaeological site of Campo Lameiro (NW Spain): an interdisciplinary approach to geoarchaeology

Resumen del trabajo presentado a la 62nd Annual Conference on Magnetism and Magnetic Materials (MMM), celebrada en Pittsburgh (USA) del 6 al 10 de noviembre de 2017.Financial support 224 from Fundacao para a Ciencia e a Tecnologia (Lisboa, Portugal) grants 225 (PTDC/CVT/2006/66114 and UID/CVT/00276/2013)Tese de doutoramento em Ciencias da Saude, apresentada a Faculdade de Medicina da Universidade de CoimbraTrabajo presentado en el 8o Congreso de la Asociacion Iberica de Endocrinologia Comparada (AIEC), celebrado en Madrid del 5 al 7 de septiembre de 2011.Trabajo presentado en la International Conference and Exposition Aquaculture Europe 2017, celebrada en Dubrovnik del 17 al 20 de octubre de 2017.O presente estudo centra-se na analise das paisagens de poder que materializam as dinâmicas sociais e territoriais ocorridas nos finais da Idade do Ferro e inicios de epoca Romana no Noroeste Peninsular. Enquadra-se numa necessidade de se desenvolverem novas e inovadoras metodologias de trabalho, aliadas a uma robustez teorica e a um rigor empirico, cujas interpretacoes permitam a criacao de um novo conhecimento e que tenha aplicabilidade a outros contextos. Esta investigacao foi desenvolvida numa optica da Arqueologia da Paisagem. Assim, adoptou-se uma perspectiva diacronica e uma metodologia interdisciplinar, procurando-se ampliar as metodologias tradicionalmente utilizadas neste tipo de estudos, sobretudo com o recurso as tecnologias geoespaciais, na tentativa de se caracterizar a estruturacao do povoamento e territorio neste periodo e area geografica. O objectivo principal deste estudo reside na tentativa de caracterizacao sociopolitica das comunidades do Noroeste Peninsular, particularmente na sua area Meridional, nos finais da Idade do Ferro e inicios de epoca Romana. Tomaremos como caso de estudo a regiao do Alto Tâmega e Cavado. Trata-se de uma zona de fronteira e de hibridizacao cultural pelo menos desde a Idade do Ferro, localizando-se justamente na transicao entre a area dos oppida ocidentais e a dos pequenos castros orientais. Nesta zona registam-se processos de intensificacao economica, embora mais centrados na exploracao de recursos minerais, ao inves da exploracao e intensificacao agricola, dando lugar a uma estruturacao territorial bastante especifica e a formas particulares de expressao da desigualdade. Procuraremos analisar as dinâmicas territoriais e os processos de continuidade e de mudanca social, bem como as diferentes economias politicas e estrategias de poder, numa epoca onde tem lugar complexas politicas de interaccao cultural, particularmente com o mundo mediterrânico, bem como uma crescente negociacao social e identitaria. Procuraremos definir e clarificar os diferentes modelos de povoamento e as diferentes formas de estruturacao territorial em epoca pre-Romana e Romana. A base fundamental deste trabalho sera a objectivacao dos criterios locacionais e territoriais de cada povoado, com vista a se discriminarem as decisoes sociais que motivaram a eleicao de um determinado sitio, ja que distintos modelos locacionais e territoriais poderao associar-se a diferentes contextos culturais e a distintas formas de organizacao territorial e sociopolitica. Todavia, sera de ressaltar que este trabalho tera sempre um sentido comparativo, procurando-se analisar a variabilidade, mais do que uma reconstrucao positiva das condicoes que possam ter influenciado a localizacao dos sitios. Alem disso, partimos da diversidade regional e da heterogeneidade cultural, ja que mais que um todo homogeneo com uma evolucao unilinear, devemos antes, segundo uma perspectiva pos-colonial, contemplar uma multiplicidade de experiencias historicas particulares a diferentes escalas antes e depois da chegada de Roma. Apos os primeiros contactos com os Romanos, documenta-se uma estruturacao complexa do povoamento do Noroeste, que se manifesta no pleno desenvolvimento de grandes povoados tipo oppidum, que actuariam como verdadeiros lugares centrais do ponto de vista politico. Este fenomeno, que se desenvolve anteriormente a criacao generalizada de novos assentamentos romanos, e arqueologicamente mais visivel na parte Meridional da Galiza e no Norte de Portugal, onde os processos de ?oppidizacao? sao mais massivos e prematuros. Contudo, este processo de sinecismo e de hierarquizacao do povoamento podera ser consequencia de dinâmicas anteriores, uma vez que nao podemos negligenciar os complexos particularismos historicos das comunidades indigenas, tal como parece suceder em outros territorios europeus. Evidentemente que o contacto e a pressao Romana pode ter acelerado e precipitado todo este processo, embora talvez nao se tenha tratado de um processo unidireccional e monocausal. E necessario percepcionar os oppida em relacao estrutural a toda uma serie de fenomenos sociais, politicos e culturais que ocorrem no sul da Callaecia entre os seculos II a.C. e I d.C..This research has been developed on the behalf of a Doctoral (M3.1.2/F/025/2007) and a Post-Doctoral (M3.1.7/F/005/2011) Research Project, both supported by the Regional Fund for Science (FRC) of the Azorean Regional Government. This work was partially funded by Portuguese National Funds through FCT – Fundacao para a Ciencia e Tecnologia (Foundation for Science and Technology), under the project “PTDC/AAC-AMB/098786/2008”.Tese de Doutoramento em Ciencias da Saude, Universidade do Minho Escola de Ciencias da Saude.Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 8 al 13 de abril de 2018Este trabajo ha sido parcialmente financiado por la Fundacao para a Ciencia e Tecnologia, Ministerio da Educacao e Ciencia, Republica Portiguesa (SFRH/BD/44089/2008) y los proyectos: “Origins and Spread of Agriculture in the western Mediterranean region (ERC-2008-AdG 230561)” y “Stable isotopes in Mediterranean natural and agricultural ecosystems: from a mechanistic understanding of isotope fractionation processes in plants to the application in paleoenvironmental research (DGI CGL2009- 13079-C02-01)”.Trabajo presentado en el 18th International Symposium on Pollutant Responses in Marine Organisms (PRIMO 18), celebrado en Trondheim (Noruega) del 24 al 27 de mayo de 2015.VI Simposio Internacional de Ciencias del Mar - VI International Symposium of Marine Sciences (ISMS 2018), 20- 22 June 2018, Vigo.-- 1 pageResumen del poster presentado a la XXXV Reunion Bienal de la Real Sociedad Espanola de Fisica y al 25o Encuentro Iberico de Ensenanza de la Fisica, celebrados en Gijon (Espana) del 13 al 17 de julio de 2015.-- et al.Trabajo presentado en el I Congresso Luso-Extremadurense de Ciencias e Tecnologia, celebrado en Evora (Portugal), del 20 al 21 de octubre de 2017The 2nd International Symposium on Submarine Canyons (INCISE2014), 29th September-1st October 2014, Edinburgh.-- 1 page, 1 figureTrabajo presentado en la 10th International Hydrogenase Conference celebrada en Szeged (Hungria) del 8 al 12 de julio de 2013.An overview of 13C nuclear magnetic resonance (NMR) spectroscopy methods and their applications in the study of the metabolism of brain cells in vitro and in the in vivo brain is presented as well as their implications for modern molecular imaging techniques. Various topics will be discussed, such as general properties of the 13C NMR spectrum, 13C NMR spectroscopy acquisition protocols, determination of fractional 13C enrichment, 13C(2H) NMR methodologies, and the use of 13C hyperpolarized substrates for NMR spectroscopy and imaging. Some illustrative applications are described, both in vitro and in vivo.This study was financially supported by Fundacao Para a Ciencia e a Tecnologia (SFRH7 BPD/5560/2001) and HP BIODIBERIA program at the Real Jardin Botanico (Madrid).Conferencia invitada. -- 7th Conference on Elementary Processes in Atomic Systems,Průhonice, Prague, September 3-6, 2017.-- https://www.jh-inst.cas.cz/tchem/cepas2017/about-cepas-2017/The current international socioeconomic context has been emphasising the need of a new set of individual competencies in order to succeed in the professional world. A new concept of employability has also emerged, with a person-centred approach, which reflects the need to deal effectively with career-related changes (Fugate, Kinicki, & Ashforth, 2004). In a psychosocial perspective, it is assumed an individual ability to adapt to social expectations and to behave according to the changing conditions (Savickas & Porfeli, 2012). On the other hand, the last decade represented a period of profound transformations in the European space of higher education, driven by Bologna guidelines. Higher education institutions are expected to adapt new ways of work organization, promoting new core competencies in future professionals. In this context, the paper will describe a research project which aims to identify and analyse the impact factors on the employability of Portuguese graduates, namely, individual characteristics, curricular experiences during graduation courses and also employer’s characteristics. This project represents an attempt to a closer and necessary articulation between higher education practices and labour market requirements.Trabajo presentado en el MedCLIVAR Conference: Bridging the Mediterranean Climates, celebrado en Belgrado (Serbia) del 17 al 21 de septiembre de 2018Trabajo presentado por Mariana Reis Sobreiro para optar al grado de Doctor por la Universidad de Salamanca y realizado en el Instituto de Biologia Molecular y Celular del Cancer.13 paginas, 7 tablas, 1 figuras, 1 apendice. Special thanks go to Ana Mouro, Joao Luis Mouro, Miguel Porto, Nuno Pires and Sara Dias for assisting in the fieldwork, and Nuno Gomes and associated workers for the EDM loan and field aid.Trabajo presentado en en 16th International Symposium on Fish Nutrition and Feeding (ISFNF 2014), celebrado en Cairns (Australia) del 25 al 30 de mayo de 2014.Tese desenvolvida no quadro do Programa Doutoral em Ciencias e Engenharia do Ambiente, com o financiamento de uma bolsa de doutoramento (SFRH/BD/42168/2007) da Fundacao para a Ciencia e a Tecnologia (FCT) e o apoio dos projectos EROSFIRE II (PTDC/AGR-CFL/70968/2006), e ”FIREREG”(PTDC/AGR-CFL/099420/2008), ambos financiados pela Fundacao para a Ciencia e a Tecnologia (FCT) e o FSE no âmbito do III Quadro Comunitario de Apoio.Editors: A. Campar Almeida, Ana M. S. Bettencourt, D. Moura, Sergio Monteiro-Rodrigues and Maria Isabel Caetano Alves. 29 pp.Trabajo presentado en el 10o Congreso de la Asociacion Iberica de Endocrinologia Comparada (AIEC), celebrado en Castellon (Espana), del 23 al 25 de septiembre de 2015Trabajo presentado en Aquaculture Europe 2019, celebrado en Berlin (Alemania), del 7 al 10 de octubre de 2019Tese de Candidatura ao grau de Doutor em Ciencias Biomedicas submetida ao Instituto de Ciencias Biomedicas de Abel Salazar da Universidade do Porto por Ana Maria Bastos Barros Neto e realizado em el Centro Andaluz de Biologia del Desarrollo, centro mixto CSIC-UPO.Trabajo presentado en el EMS Annual Meeting: European Conference for Applied Meteorology and Climatology, celebrado en Dublin (Irlanda), de 4 al 8 de septiembre de 2017

Mineral dust as a driver of carbon accumulation in northern latitudes

Peatlands in northern latitudes sequester one third of the world’s soil organic carbon. Mineral dusts can affect the primary productivity of terrestrial systems through nutrient transport but this process has not yet been documented in these peat-rich regions. Here we analysed organic and inorganic fractions of an 8900-year-old sequence from Store Mosse (the “Great Bog”) in southern Sweden. Between 5420 and 4550 cal yr BP, we observe a seven-fold increase in net peat-accumulation rates corresponding to a maximum carbon-burial rate of 150 g C m−2 yr−1 – more than six times the global average. This high peat accumulation event occurs in parallel with a distinct change in the character of the dust deposited on the bog, which moves from being dominated by clay minerals to less weathered, phosphate and feldspar minerals. We hypothesize that this shift boosted nutrient input to the bog and stimulated ecosystem productivity. This study shows that diffuse sources and dust dynamics in northern temperate latitudes, often overlooked by the dust community in favour of arid and semi-arid regions, can be important drivers of peatland carbon accumulation and by extension, global climate, warranting further consideration in predictions of future climate variability.

A Multi-Disciplinary Study of Woodcrafts and Plant Remains that Reveals the History of Pontevedra’s Harbour (Northwest Iberia) Between the 13th and 19th Centuries AD

Waterlogged woodcrafts and other plant remains were recovered at 65 Arcebispo Malvar Street (Pontevedra, Spain) from contexts from the 13th to 19th centuries AD, although most of the artefacts were...