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IX Simposio de Estudios Polares del Comité Español del Scientific Committee on Antarctic Research (SCAR), 5-7 September 2018, Madrid, España.-- 1 page, Se muestreó la comunidad microbiana en Cambridge Bay, Canada, entre primeros de marzo y finales de junio. Se construyeron metagenomas con muestras de tres tamaños (200-20 μm, 20-3 μm y 3-0,2 μm), bajo el hielo y a 40 m. Analizando los fragmentos correspondientes al rDNA 16S pudimos seguir la composición de la comunidad planctónica desde el invierno tardío (bajo el hielo), pasando por la época de fusión del hielo y hasta la proliferación algal de verano (en aguas libres de hielo). La comunidad invernal estaba dominada por alfa y gama Proteobacteria y Thaumarchaeota. En verano, disminuyeron las Taumarchaeota y las alfaProteobacteria. En cambio, las Flavobacterias aumentaron desde un 12 a un 25% del total. Entre estas, los miembros del género Polaribacter pasaron a ser dominantes (70% de todas las secuencias de Flavobacterias). Después del ensamblaje y anotación de los metagenomas, se pudieron detectar más de dos millones de genes, la mayoría con asignación taxonómica fiable. También se pudieron reconstruir unos 600 genomas de bacterias y arqueas (MAGs). De este modo pudimos identificar los taxones responsables de los cambios temporales en la comunidad. En particular seguimos las abundancias e identidades de tres tipos de genes: la proteorodopsina, los enzimas degradadores de polímeros y los involucrados en la adquisición de nutrientes.El caso de la proteorodopsina resultó intrigante. En una campaña anterior en la misma zona detectamos un pico en la expresión del gen coincidente con la rotura del hielo. Después el gen permaneció silencioso durante mayo y parte de junio, para volver a expresarse a mediados de junio. En el momento del pico de expresión la mayoría de las PR pertenecían a alfaProteobacterias seguidas de gamma Proteobacterias y Flavobacterias, mientras que en los meses siguientes disminuyeron las gamma Proteobacteria y aumentaron las Flavobacterias. De todos modos parece que la PR no juega ningún papel en el aumento de las Flavobacterias durante la primavera. De hecho, el MAG más abundante de Polaribacter reconstruido, no tenía el gen de la PR. Seguramente, el aumento de Flavobacterias se debe a la degradación de polisacáridos procedentes de las algas del hielo. Mientras que los productos de la proliferación de fitoplancton en junio serían explotados conjuntamente por Proteobacterias y Flavobacterias. Combinados con los estudios que realizamos en las campañas CASES (2003-2004) y CFL (2007-2008) en las que pudimos seguir la comunidad microbiana desde otoño hasta el verano siguiente, empezamos a tener un modelo del funcionamiento de estos microorganismos durante las épocas más desconocidas del año

Trabajo presentado en el 88 National Congress of the Italian Geological Society: Geosciences on a changing planet: learning from the past, exploring the future, celebrado en Nápoles (Italia), del 7 al 9 de septiembre de 2016, The decay of pottery in underwater environments is a complex phenomenon so far poorly investigated, since a multitude of factors is involved. Degradation forms in seawater imply not only a variation in the physico-mechanical and chemical properties of the material, but also an aesthetic alteration, due to superficial deposits, which can determine to the illegibility of the artifacts. In this context, it is crucial to determine to what extent these decay factors, mainly attributable to biological growth, could affect the durability of pottery and what are the effects of cleaning procedures. Several fragments of pottery from the submerged archaeological site of Baia (Naples, South Italy) were collected and subject to different investigations. The interaction between the biological colonization and the archaeological materials was evaluated by means of stereomicroscopy and scanning electron microscopy. Then, considering that carbonatic encrustations are the main degradation products identified, some chemical and mechanical cleaning procedures have been tested for their removal. In order to check the most suitable method, some petrophysical properties were measured, such as surface roughness and ultrasonic velocity in order to evaluate change occurring in pottery properties after the removal of the degradation layers.

Trabajo presentado en el 5th YOuth in COnservation of CUltural Heritage, celebrado en Madrid (España) del 21 al 23 de septiembre de 2016

Trabajo presentado en el IX Congresso Nazionale AIAR, celebrado en Arcavacata di Rende (Italia) del 9 al 11 de marzo de 2016, The decay of materials in underwater environments has been poorly understood for its complexity, since a multitude of factors are involved including hydrodynamic variables, hydrochemical and geochemical features, sedimentary dynamics and biological communities [Fernández-Montblanc et al. 2014, La Russa et al. 2015]. This work is focused on the study of the deterioration processes derived from the biological colonization in seawater conditions, in geomaterials broadly used in cultural heritage. To this end, two types of marble (the Italian Carrara and the Spanish Macael), broadly used in cultural heritage, were subjected to an environment exposition test. Samples were submerged for one and a half year in a submarine archaeological area in the Bay of Cadiz (southern Spain), Bajo del Chapitel, considered as Cultural Interest and recognized as Archaeological Zone in the General Catalogue of the Andalusian Historical Heritage. This area includes remains of the shipwreck Bucentaure, sunken during the Trafalgar Battle (1805), along with remains of Roman and Punic ships. Three types of conditions were considered simulating the original position in which archaeological objects could be exposed in the sea bottom (Type I-fully exposed to seawater, Type II-half-buried and Type III-covered, simulating burial). The characterization of Carrara and Macael marbles by polarized optical microscopy and fluorescence and diffraction X-ray techniques showed differences in grain size and mineral composition. The biological colonization and the interaction with the substrate was investigated under stereomicroscope and scanning electron microscopy revealing that the extension of the colonization and the decay associated was more related to the type of exposure underwater condition than to the intrinsic characteristics of the materials. The largest bio-cover was observed in those samples subjected to the condition Type I (30-35%). This colonization consisted of superficial deposits and encrustations mainly attributable to remains of serpulids tubes and barnacle shells, that cause aesthetic damage and micro-fractures subparallel to the marble surface. In addition, the bioerosion phenomena in the form of microperforations (micro-pitting), was also detected in the three types of conditions, but with more intensity in Macael and Carrara samples fully exposed and half-buried. The origin of these microperforations is probably attributable to the action of endolithic microorganisms. This study constitutes an ideal assessment of biodeterioration processes in underwater cultural heritage, which could contribute to improve conservation measures aimed to the in situ preservation (Rule 1 of the Annex of the UNESCO 2001 Convention for the Protection of the Underwater Cultural Heritage) and musealization of underwater archaeological sites., Community of Madrid for financing Geomateriales2 program (P2013/MIT2914), CEI-Moncloa UCM-UPM, Applied Petrology for Heritage Stone Materials Conservation Research Group.

In this study the effect of human urine on lithobiontic microorganisms colonizing stone materials from the cultural heritage was evaluated in situ by means of a field experiment in a historic quarry (Redueña dolostone quarry, Madrid, Spain). With this experiment, it was possible to assess the effect of this bioproduct when interacting with the existing lithobiontic microbial community at the most real conditions. The application of the bioproduct was performed by directly spraying onto the rock surface of the quarry front with abundant lichen colonization during 8 weeks (one application per week). After the application, the structure of Verrucaria nigrescens lichen thalli and the ultrastructure of their algal and fungal cells components resulted to be affected. The upper cortex of the lichen thalli was particularly affected, with damage-like fungal cells, and even in some cases, disappeared, leaving unprotected and exposed algal cells to environmental conditions., This work was supported by the GEOMATERIALES 2 programme (S2013/MIT-2914/ GEOMATERIALES 2), Comunidad de Madrid) and FSE and FEDER.

rabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 12 al 17 de abril de 2015, The increase in the number of pets (mostly dogs), homeless people and the more recent open-air drinking sessions organized by young people in historical centers of European cities, derive on the augmentation of urinations on stone façades of the built cultural heritage. Up to now this process has been considered only under an undesirable aesthetical point of view and the insalubrious conditions it creates, together with the cleaning costs that the local governments have to assume. This study aims to confirm urine as a real source of soluble salts that can trigger the decay of building materials, especially of those of built cultural heritage of the historical centers of the cities, which are suffering the new social scenario described above. For this purpose, an experimental setup was designed and performed in the laboratory to simulate this process. 5 cm side cubic specimens of dolostone were subjected to 100 testing cycles of urine absorption by capillarity. The necessary amount of urine was collected by donors and stored following clinical protocol conditions. Each cycle consisted of imbibitions of the specimens in 3 mm high urine sheet for 3 hours, drying at 40ºC in an oven for 20 hours and 1 hour cooling in a dessicator. At the end of the 100 cycles, small pieces of the specimens were cut, observed and analyzed with the aid of an environmental scanning electron microscope, which presents the advantage of no sample preparation. The sampled pieces were selected considering there were different sections in height in the specimens: a) a bottom section that corresponds to the section that has been immersed in the urine solution (3 mm); b) an interface section, immediately above the immersed area, which is the area most affected by the urine capillarity process, characterized by a strong yellowish color; c) the section that we have named as section of influence, which is subjected to the capillary absorption, although not so strongly than the interface section (these 3 sections, a) b) c) represent the first one centimeter of the specimen from the bottom); d) and the fourth and top section, which shows no influence by the effect of urine capillary absorption. The obtained results showed, from bottom to top, the following crystallized salts: a) abundant prismatic crystals enriched in P and Ca (calcium phosphate); b) amorphous round-shaped potassium sulfate crystals and cubic sodium chloride crystals embedded in an organic matrix; d) cubic sodium chloride crystals are dominant. In the unaffected area, no other crystals were detected different from the carbonate minerals forming the rock. These results are in accordance to which has already been published by the authors in granitic materials (Cámara et al 2014)., Geomateriales 2 programme (S2013/MIT-2914) funded by the Community of Madrid

Received 23 September 2014, This study explores the photosynthetic microbial colonization of rhyolitic ignimbrites in Lomas de Tilocalar, a hyper-arid region of the Atacama Desert, Chile. Colonization appeared in the form of a green layer a few millimeters beneath the ignimbrite surface. Some ignimbrite rocks revealed two distinct micromorphological areas of identical mineralogical and chemical composition but different textural properties. According to texture, colonization patterns varied in terms of the extension and depth of colonization. The diversity of photosynthetic microorganisms was assessed by denaturing gradient gel electrophoresis (DGGE) of the 23S rRNA gene and by generating clone libraries of the 16S rRNA gene. We observed a low diversity of photosynthetic microorganisms colonizing the ignimbrite microhabitat. Most rRNA gene sequences recovered greatly resembled those of Chroococcidiopsis hypolith clones from arid deserts. These results point to highly restrictive conditions of the hyper-arid Atacama Desert conditioning the diversity of cyanobacteria, and suggest that microbial colonization and composition patterns might be determined by the microscale physicochemical properties of the ignimbrite rocks., This study was supported by grants CGL2010-16004 and CTM2012-38222-C02-02 and CGL2013-42509 from the Spanish Ministry of Economy and Competitiveness and by a predoctoral FPI fellowship program (BES-2007-15145).

El Programa Geomateriales Durabilidad y conservación del geomateriales del patrimonio construido, enmarcado en el IV Plan Regional de Investigación Científica e Innovación Tecnológica (IV PRICIT), fue concedido a través de su Convocatoria de Programas de I+D en Tecnologías 2009 (orden 679/2009). Iniciado el 1 de enero de 2010 y finalizado el 31 de mayo de 2014, el programa de investigación se plantea con una clara concepción experimental, pretendiendo dar solución y optimizando las actuaciones aplicadas para mejorar la durabilidad y conservación de los geomateriales utilizados en el patrimonio construido. El consorcio que integra el programa está constituido por grupos de investigación que desarrollan su labor en la Comunidad de Madrid, pertenecientes a la Agencia Estatal del Consejo Superior de Investigaciones Científicas (CSIC), a la Universidad Complutense de Madrid (UCM) y a la Universidad de Alcalá de Henares (UAH), otros grupos, laboratorios y/o centros tecnológicos ubicados en otras provincias españolas y en países europeos así como empresas privadas y otros organismos de colaboración. El programa ha conseguido alcanzar los objetivos científico-tecnológicos planteados, en gran parte mediante la colaboración de los diferentes grupos integrantes, jugando un papel esencial la participación también en el programa del Laboratorio de Petrofísica (RedLab 217). El presente volumen recoge las ponencias presentadas en la Reunión Científica del Programa Geomateriales, celebrada el 9 de octubre de 2013. Estas ponencias se organizaron fundamentalmente en base a los objetivos científicos del programa, incidiendo en las principales actividades realizadas y resultados obtenidos, y apostando por los jóvenes investigadores incorporados. En los resúmenes incluidos se pretende resaltar, por un lado, los resultados científicos de mayor relevancia, las investigaciones que han generado el desarrollo de patentes, las colaboraciones establecidas entre los diferentes grupos y/o empresas y las previsiones futuras. Por otro, aspectos relacionados con los objetivos de formación, como la realización de tesis doctorales y movilidad de investigadores, así como la participación conjunta en los objetivos de difusión y en actividades de gestión de los diferentes miembros del programa. El Programa Geomateriales ha supuesto un importante avance del conocimiento, permitiendo los logros científicos obtenidos posicionar al consorcio en unas condiciones muy favorables respecto a las diversas temáticas implicadas en la conservación del patrimonio. Este aspecto hace del consorcio el único a nivel nacional que aborda su estudio de forma integral y confirma, una vez más, la necesidad y conveniencia de crear equipos de trabajo que apuesten por la colaboración y conjunción de esfuerzos para alcanzar mayores y mejores logros.

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Ciencias, Departamento de Biología. Fecha de lectura:18-12-2012

The hyper-arid core of the Atacama Desert is considered the driest and most life-limited place on Earth. As such, this desert is an ideal environment to study the survival and biological adaptation strategies of microorganisms to this extremely dry environment. The extreme aridity of the Atacama Desert allows us to address questions such as the potential for life in extraterrestrial environments such as the surface of Mars. Our results over the last six years of searching for microbial life in the hyper-arid core of the Atacama Desert shows the presence of various habitats capable of sustaining active microbial ecosystems. All of them belong to endolithic – inside the rocks – microbial habitats. We suggest that these endolithic habitats protect microbial communities from UV and excessive PAR radiation and supply increased moisture, thus providing environmental refuges – or islands of life - in the desert. This «archipelago» of microbial islands of life is composed by the following endolitically colonized substrates: a) halite rocks (Wierzchos et al., 2006; de los Ríos et al., 2010); b) gypsum crusts (Wierzchos et al., 2011), c) volcanic origin ignimbrite (Wierzchos et al., 2012) and d) rhyolite and calcite rocks (DiRuggiero et al., submitted)., Trabajo presentado en el 9th International Congress EXTREMOphiles, celebrado en Sevilla del 10 al 13 de septiembre de 2012.

4 páginas, 2 figuras. Ed. Miguel Ángel Rogerio Candelera y Cesáreo Sáiz Jiménez. Primera Reunión de la Red de Ciencia y Tecnología para la Conservación del Patrimonio (Madrid, 28-29 de junio de 2011)., El grupo ECOGEO que pertenece en la actualidad a El Museo Nacional de Ciencias Naturales (CSIC), comenzó sus trabajos de investigación en las interfases talo liquénico-sustrato lítico, hace casi cuatro décadas.

Una biocolonización importante por líquenes y hongos no liquenizados sobre calcarenitas se desarrolló en menos de 40 años en un medio semiárido en zonas favorables de retención de humedad en los elementos decorativos del Puente Viejo de Elche (España), especialmente en la capilla dedicada a Nuestra Señora de la Asunción. Dicha biocolonización presenta un patrón, relacionado con las características textoestructurales de la roca, especialmente con la porosidad interpartícula, que se expone en este trabajo. Los talos liquénicos están muy estrechamente unidos a la piedra y las hifas del micobionte que penetran en ella ejercen una importante función promotora de disgregación granular.

13 páginas, 13 figuras, La colonización biológica induce en la piedra además de daños estéticos, una serie de procesos de alteración mecánica y química que generan biodeterioro del monumento. El grupo de investigación de Ecología Microbiana y Geomicrobiología del sustrato Lítico, del Instituto de Recursos Naturales del CSIC, cuenta con una estrategia de actuación para llevar a cabo el diagnóstico de los fenómenos del biodeterioro de piedra monumental en la que por combinación de técnicas de microscopía in situ y de biología molecular, es posible analizar los procesos de alteración producidos, los microorganismos implicados, y con ello, plantear y posteriormente evaluar tratamientos encaminados a eliminar o reducir los fenómenos de biodeterioro., Financiación de la Comunidad de Madrid a través del Proyecto MATERNAS (S0505-MAT/000094). Nuestro grupo de Investigación quiere agradecer la ayuda técnica de Teresa Carnota, Sara Paniagua, Fernando Pinto, Isabel Salmeán y Charo Santos.

This study examines the deterioration of geomaterials used throughout history that today may be found lying on the ocean floor. Submerged archaeological sites including cargoes from shipwrecks or ancient city ruins have been a topic of interest from a perspective of in situ musealization, as a way of making underwater cultural heritage accessible to the public. In an experimental study conducted at an underwater archaeological site in the Bay of Cádiz (SW Spain), we subjected two types of marble (Carrara and Macael) to three conditions to which submerged archaeological objects are often exposed: full exposure to the water column, natural processes of burial and unearthing, or permanent burial. After an 18-month study period, the factor found to mostly affect these materials was their biological colonization. This factor was assessed by estimating total surface biocover and the rate of surface biocolonization, and also through the identification of skeletons and associated alteration forms by light microscopy, and scanning electron microscopy (SEM). Biofouling and bioerosion were the main causes of biodeterioration and dependent on the position of the marble specimens in the seawater. The response of both materials was similar, though dolomite crystals in the Carrara marble acted as a protective barrier against actively penetrating microorganisms. These investigations have allowed the study of tracers left by epilithic encrusting organisms and endolithic bioeroders on marbles intentionally exposed to seawater, providing new insights to the understanding of the biodeterioration processes occurring in cultural heritage stones, with significant implications when they are part of underwater archaeological remains., This research was funded by the Regional Government of Madrid (CAM) (Geomaterials 2, S2013/MIT_2914) and by the Spanish Ministry of Economy and Competitiveness (ARQUEOMONITOR, CTM2010-16363).