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Abstract As a consequence of on-going global warming, the ocean is losing oxygen, which has implications not only in terms of marine resources management and food supply but also in terms of the potentially important feedback on the global carbon cycle and climate. Of particular scrutiny are the extended zones of already low levels of oxygen called the oxygen minimum zones (OMZs) embedded in the subsurface waters of the productive Eastern Boundary Upwelling Systems (EBUS). These OMZs are currently diversely simulated by state-of-the-art Earth System Models (ESM) hampering a reliable projection of ocean deoxygenation on marine ecosystem services in these regions. Here we focus on the most emblematic EBUS OMZs of the planet, that of the South Eastern Pacific (SEP), which is under the direct influence of the El Niño Southern Oscillation (ENSO), the main climate mode on interannual timescales at global scale. We show that, despite the low consensus among ESM long-term projections of oxygen levels, the sensitivity of the depth of the upper margin (oxycline) of the SEP OMZ to El Niño events in an ensemble of ESMs can be used as a predictor of its long-term trend, which establishes an emergent constraint for the SEP OMZ. Because the oxycline along the coast of Peru and Chile deepens during El Niño events, the upper bound of the SEP OMZ is thus likely to deepen in the future climate, therefore oxygenating the SEP OMZ. This has implications not only for understanding the nitrogen and carbon cycles at global scale but also for designing adaptation strategies for regional upper-ocean ecosystem services.

Mountain ecosystems located in the Andes cordillera of central Chile (29–35°S) have been strongly affected by the ongoing Mega Drought since 2010, impacting the snow cover, the surficial water resources (and thereby water storage), as well as the mountain biota and ecosystem services. Paleoenvironmental records in this part of the semiarid Andes are key to estimating the effects of past climate changes on local communities helping to forecast the ecological and biological responses under the aridification trend projected during the 21st century. Here we present a 2400-year multiproxy paleoenvironmental reconstruction based on pollen, diatoms, chironomids, sedimentological and geochemical data (XRF and ICP-MS data) of Laguna El Calvario (29°S; 3994 m a.s.l), a small and shallow Andean lake. Four main hydrological phases were established based on changes in the lithogenic and geochemical results associated with allochthonous runoff input and the subsequent response of the biological proxies. Between 2400 and 1400 cal yrs BP, wetter than present conditions occurred based on the intense weathering of the lake basin and the dominance of upper Andean vegetation. A decrease in moisture along with sub-centennial discrete wet pulses and lake-level changes occurred until ~800 cal yrs BP followed long-term stable climate conditions between 1850 and 1950 AD as suggested by a drop in vegetation productivity and low lake levels. From 1950 AD to the present, a decline in moisture with a severe trend to drier conditions occurring in the last decades occurred as reflected by an upward vegetation belt displacement around Laguna El Calvario along with a turnover of diatom assemblages and high productivity in the water column.

The oxygen minimum zone (OMZ) is an essential feature along the Pacific margin, extensively studied for its influence on benthic fauna, acquiring relevance in coastal zones due to its impact on aquaculture species, marine-managed areas, and marine-protected areas. The most evident temporal variability beyond seasonal timescales observed for the OMZ was related to inter-annual variability associated with El Niño, when warmer and more oxygenated waters arrive at shallower zones and the OMZ becomes deeper. However, the impact of oxygen-deficient water that appears sporadically over the shelf is not yet understood. This study provides an integrated view of the oceanographic and climatic conditions behind bottom oxygen conditions along the Chilean continental margin, considering the temporal variability in the South East (SE) Pacific during the last ~2000 years. We organized the information on redox-sensitive metals and δ15N from sedimentary cores obtained from shelf zones from 23°S to 36°S at water depths lower than 100 m. The results demonstrate the variability in the upper part of the OMZ over the shelf, which seems to respond to climatic oscillations. The element distribution indicated in particular a more intense OMZ was developed over the shelf before 1400 AD, followed by more oxygenated bottom conditions afterward, except between 1925 and 1970 off 36°S when the OMZ was intensified, a condition that was not observed at the northern sites. This period mostly coincided with a low Pacific Decadal Oscillation amplitude and reduced El Niño Southern Oscillation (ENSO) activity. In the last 50 years, the proxy data suggests less intense suboxic environment along the Chilean margin. This weakening of the upper boundary of the OMZ in the last decades is interpreted as resulting from the accumulative effect of ventilation processes at different time scales.

Mejillones Bay is located in northern Chile (23°S) and is influenced by an Oxygen Minimum Zone (OMZ), with oxygen levels below 0.5 ml l–1. This area presents particular ecological characteristics, such as circulation of currents, hotspot, high productivity and industrial activity. This extreme ecosystem generates the need to understand their dynamics and changes across time and space, as well as to identify the main differences with other OMZs. For this reason, we studied the benthic foraminifera to use them as environmental and oxygenation proxies. For this purpose, two sediment cores (ZA and Z1A) were collected, obtaining 14 samples of the first 8 cm (vertical distribution), and 18 samples with a mini boxcore (spatial distribution). When analyzing the foraminifera community, some similarities were found in environmental characteristics of other OMZs, such as the predominance of Bolivina seminuda, Bolivina costata, Epistominella exigua, Fursenkoina sp., and Nonioella stella (species typical of hypoxic conditions). In addition, a high abundance of angular-asymmetric morphologies was observed, indicating eutrophied silty substrates and low current circulation. However, the Mejillones Bay recorded a particular spatial and vertical dynamics respect to others OMZs, due to presence of other species of Bolivinids not reported for this area before, and a high abundance of Buliminella elegantissima, which is not recorded in most of OMZs. Foraminifera with rounded-symmetric morphologies were present and dominant in deeper layers, reflecting a turbulent and high-energy environment. On the basis of depth and conditions of microxia or dysoxia, no significative pattern of spatial and vertical distribution was observed. The latter can be explained by local factors such as cyclonic and anticyclonic whirlpools, wastewater from industrial activity and natural disaster such a Tsunami occurred in 1877. These factors contributed to the mixture of the benthic foraminifera and prevented the formation of spatial and vertical patterns. Finally, an intensification of hypoxia was identified, indicating microxia (0,01 ml l–1) in the superficial layers (0–3 cm from years 1996 to 2012), while the deeper layers (4–8 cm from years 1985 to 1877) presented foraminiferal species that indicated dysoxia conditions (0,07 ml l–1). The latter differs from other OMZs, which show greater oxygenation in the most superficial layers and microxia in deeper layers. This study represents the first ecological reconstruction using benthic foraminifera proxies for the Mejillones Bay, which results indicate an OMZ with ecological and environmental features that differ from other OMZs.

Mesophotic and deeper habitats (∼40 to 350 m in depth) around Rapa Nui (Easter Island) were investigated using a remotely operated vehicle. We observed extensive fields of filamentous cyanobacteria-like mats covering sandy substrates and mostly dead mesophotic Leptoseris spp. reefs. These mats covered up to 100% of the seafloor off Hanga Roa, the main village on the island, located on its western side. The highest mortality of corals was observed at depths between 70 and 95 m in this area. Healthy Leptoseris reefs were documented off the northern and southeastern sides of the island, which are also the least populated. A preliminary morphologic analysis of samples of the mats indicated that the assemblage is composed of at least four filamentous taxa, including two cyanobacteria (cf. Lyngbya sp. and Pseudoanabaena sp.), a brown alga (Ectocarpus sp.), and a green alga (Cladophora sp.). An ongoing eutrophication process is suggested as a potential driver of the proliferation of these filamentous mats off Hanga Roa village.

Two stations representing coastal and shelf environments (bay of Concepción and adjacent shelf, respectively) were sampled in order to assess benthic nitrogen fluxes. During the study period anomalously high oxygen bottom waters conditions were observed, coinciding with the 1997-1998 El Niño event. From both sites, intact sediment cores were collected for incubation experiments to directly estimate total ammonium fluxes. Pore-water chemistry was also assessed to estimate diffusive fluxes of nitrogen compounds (NH4+, NO3- and NO2-). The NH4+ flux from incubation experiments ranged from 0.55 to 2.18 mmol m-2 day-1 in the inner bay and from 1.84 to 2.14 mmol m-2 day-1 on the shelf. NO3- diffusive fluxes to the sediments were observed in the bay in March (-17 x 10-2 mmol m-2 day-1)and on the shelf in November (-2.7 x 10-2 mmol m-2 day-1), associated with the lowest NH4+ diffusive fluxes and coincident with a stronger gradient of Eh in the first centimeters of the sediments. Besides, total NH4+ fluxes lower than in normal periods were observed, suggesting the influence of less reducing conditions, consequence in turn of the lower fluxes of particulated organic material and higher dissolved oxygen in the bottom waters. These conditions were probably imposed by the El Niño event. On the other hand, and relative to previous reports, an increase of irrigation coefficients (DI) was estimated. Thus, the flux extension of other nitrogen compounds could have acquired relevance in relation to NH4+ fluxes during the study periodSe analizaron los flujos de compuestos nitrogenados desde los sedimentos en dos áreas representativas de condiciones costeras y de plataforma (Bahía Concepción y plataforma adyacente, respectivamente). Durante el período de muestreo las aguas de fondo presentaron un anómalamente alto contenido de oxígeno disuelto, coincidente con el evento El Niño 1997-1998. De ambos sitios, se incubaron testigos de sedimento intactos para determinar los flujos totales de NH4+. Además se determinó la concentración de NH4+, NO3- y NO2- en el agua intersticial para estimar los flujos difusivos de compuestos nitrogenados en la interfase agua-sedimento. Los flujos de NH4+ totales variaron entre 0,55 y 2,18 mmol m-2 día-1 al interior de la bahía y entre 1,84 a 2,14 mmol m-2 día-1 en la plataforma. Se observaron flujos difusivos de NO3- en dirección a los sedimentos al interior de la bahía en Marzo de 1998 (-17 x 10-2 mmol m-2 día-1)y en la plataforma en Noviembre de 1997 (-2,7 x 10-2 mmol m-2 día-1) asociados a los flujos difusivos de NH4+ más bajos, coincidiendo esto con la mayor gradiente de Eh en los sedimentos superficiales. Además, los bajos flujos de NH4+ medidos en comparación con mediciones previas, sugieren la influencia de un ambiente menos reductor, generado a su vez por la disminución del flujo de material orgánico particulado y por el aumento de las concentraciones de oxígeno disuelto en las aguas del fondo. Estas condiciones fueron generadas probablemente por el evento El Niño. También, con relación a reportes previos se registró un incremento en los coeficientes de irrigación (DI). Todo esto sugiere que durante este período los flujos de otros compuestos nitrogenados podrían haber adquirido relevancia con relación a los flujos de NH4+

During the last decade, the policy efforts aiming to tackle the NEET situation (young people who neither study nor work) have increased dramatically in the European Union. Meanwhile, many studies challenged those policies, showing how they failed due to lack of understanding the NEETs. Thus, we analyse the factors that influence the appearance, modification and elimination of a NEET identity. The results reveal the presence of a shared NEET identity in the countries with high NEET rates, despite the considerable differences in the countries’ and NEETs’ characteristics. The NEET rate stands out as the key factor influencing the NEET identity, showing that this identity depends more on economic cycles than on the specific country or its culture.

In a period of high rates of glacier retreat, increasing meltwater discharge from tidewater glaciers can influence marine fjord ecosystems due to increase sediment delivery and accumulation rates in the proglacial environment. Glacier variations and associated changes in glacimarine processes are recorded in the sedimentary record and submarine geomorphology of fjords. In October-November 2017, CIMAR23 Cruise surveyed several fjords adjacent to the Southern Patagonian Icefield (SPI). In this study, we show detailed results of the multibeam bathymetry, backscatter and sub-bottom seismic profiles, and sediment core samples from Europa Fjord, located west of the central SPI area, to improve the analysis of the fjord glacial and sedimentary evolution and to connect its behavior with the other fjords in the region. For the cores 210Pb chronology, magnetic susceptibility, organic carbon, total nitrogen, and stable isotopes (δ13Corg, δ15N) were performed. The seafloor geomorphology showed that the most prominent submarine landforms are transverse morainal ridges, which indicate past stillstand glacier positions; these features formed during the deglaciation of the fjord (latest Pleistocene), and some, perhaps more recently during short episodic advance/retreat events. In the central and mouth fjord areas, erosional features such as lineations are found on the rocky bottom and interpreted as formed by past grounded glaciers. Several submarine moraines are generally well preserved, but some parts are crumbled by slope failures and erosion. Most of the seismic sections are interpreted as the expected subglacial-ice proximal-ice distal succession of facies, characteristic of single retreat environments. The sedimentary record includes bioturbed muds with muddy laminations and variable amounts of coarse sediments interpreted as ice rafted debris, suggesting a proglacial environment, punctuated by calving. From the beginning of the twentieth century there is a tendency to an increase in the terrigenous organic material content, including an abrupt increase during the 80–90s, and a decline in the last decade. This behavior is indicating possibly a general increase of surface terrestrial runoff and, for the last decade, an increase of glacial meltwater input which would be caused by an accelerated deglaciation.

En este artículo se analizan algunas de las dificultades que en la práctica de investigación se han identificado en dos espacios rurales en los estados de Oaxaca y Tabasco en México, y se exponen los múltiples desafíos que el investigador debe afrontar, especialmente en relación con los conceptos de colaboración e intervención durante el trabajo que realiza. Si bien este se basa en tareas específicas de indagación y colaboración, suele haber acciones de desarrollo ajenas al entorno comunitario, que incluso no son clara o conscientemente percibidas por los actores protagonistas. Es así que el objetivo de esta presentación es reflexionar sobre la práctica investigativa colaborativa, exponiendo los aciertos y desaciertos del proceso. El concepto de intervención social se asocia con el de investigación colaborativa, en tanto que ambos pretenden poner en el centro de la participación a los sujetos, sin embargo es necesario delimitar las implicaciones de cada uno de estos conceptos en los casos estudiados. En este texto se describen aspectos teóricos y metodológicos acerca de la intervención social y la investigación colaborativa con enfoque en derechos humanos, y se reflexiona en torno al proceso de acompañamiento y las decisiones que se adoptan durante la investigación, así como acerca de la experiencia del diálogo con los colectivos con los que se colabora para construir conocimiento. This work analyzes some difficulties found in the practice of collaborative research in rural areas in Mexico, each with its historical peculiarities and passed through the application of public policies or economic policies. The researcher's activist participation has multiple advantages in that it applies development concepts outside the community environment that are sometimes not reflected by the protagonist actors. The objective of the text is to reflect on the collaborative research practice, exposing the successes and failures of the process and the challenges to overcome. As part of the research experience, the concept of social intervention is discussed, which is associated with collaborative research, in the center of participation is understood by the subjects. In this text are described the concepts and methodological aspects raised by the specialists in the subject of social intervention, then associate it with collaborative research with a human rights approach. The two collaborative research experiences focussed are described, and we reflect on the accompaniment process and the reflections on the decisions regarding the objectives, methodology and results, as well as the experience of the dialogue with the collectives with the collaboration for knowledge.

Esta investigación analiza la maternidad transnacional de mujeres inmigrantes negras, particularmente haitianas, quienes han vivenciado situaciones de discriminación y vulnerabilidad en diferentes servicios de salud públicos, donde son categorizadas como madres descariñadas o no suficientemente buenas. Los resultados apuntan a una carga dolorosa y persistente de la maternidad transnacional dichas mujeres, así como desconocimiento de parte de profesionales sanitarios sobre ésta. También se visualizan sesgos patriarcales, clasistas, racistas y xenófobos en su atención, respecto de sus prácticas de crianza y apego. Las conclusiones apuntan a un trato interseccional de estas discriminaciones, para mejorar el trato en salud a mujeres afrodescendientes.

El presente artículo informa sobre la investigación realizada entre 2013 y 2017 acerca de la enseñanza de alumnado con discapacidad visual en los Conservatorios de Música, recogiendo los recursos y buenas prácticas más destacadas que se revelaron sobre el fomento de la inclusión para estos centros, siendo también muchas de ellas extrapolables a las escuelas de música y/o las agrupaciones musicales que integran ciegos. Se parte de las dificultades de la temática en la reducida bibliografía y que el profesorado de música no cuenta con la suficiente información, experiencia y formación previa para instruir a estudiantes invidentes (Chaves, Godall y Zattera, 2015; Chávez, 2010; Dias, 2010). La metodología de la investigación fue la etnografía a partir de un diálogo de saberes entre alumnado con discapacidad visual, sus familias y docentes junto a especialistas de este campo. Para la evaluación de los resultados se conectó con la metodología del “juicio de expertos”, que evaluaron las estrategias y los recursos. Finalmente esta investigación visibiliza las prácticas que son útiles para el desarrollo de una educación inclusiva musical para alumnado con discapacidad visual.

ResumenTrabajar con personas en riesgo en exclusión social supone una labor donde la heterogeneidad y complejidad de realidades se encuentran presentes en la labor diaria del profesional de la intervención social, donde el vínculo entre el profesional y la persona de riesgo es fundamental para el desarrollo de dicho proceso social.El objetivo de esta investigación es conocer las opiniones y estereotipos que los agentes sociales y/o educativos tienen sobre las personas para quienes trabajan, en este caso en riesgo de exclusión social. Los participantes son 20 agentes sociales y/o educativos, tanto de ONG´s como de la administración pública. El instrumento utilizado para recoger información ha sido una entrevista semiestructurada, organizada por categorías de interés. Los resultados obtenidos de la investigación ponen de manifiesto la necesidad de formación en inteligencia emocional, entre otros aspectos, de los agentes educativos y sociales que trabajan con personas en riesgos de exclusión, personas que son valoradas negativamente en la sociedad y encasillados y que necesitan, según los agentes educativos y sociales adquirir competencias emocionales.Palabras claves: Inteligencia emocional, Exclusión social, agentes sociales y agentes educativos, vinculo. AbstractWorking with people at risk in social exclusion is a task where heterogeneity and complexity of realities are present.The link between the social intervention professional and the person at risk is fundamental to the social process. The objective of this research is to know the opinions and stereotypes that social and / or educational agents have about the people for whom they work, in this case at risk of social exclusión. The participants are 20 social and / or educational agents who work in Ong´s and in the public administration. The instrument used to collect information has been a semi-structured interview, organized by blocks of interest. The results obtained from the research reflect the need for training in emotional intelligence, among other aspects, of educational and social agents working with people at risk of exclusion, people who are negatively valued in society and pigeonholed and who need, according to Educational and social agents acquire emotional skills.Keywords: Emotional intelligence, social exclusion, social agents, educational agents and link. Data de receção: 29/12/2019Decisão Final: 22/06/2020

The rates of young people Not in Education, Employment or Training (NEET) in the Mediterranean European Economic Area (MED EEA) are high. Hence, the European Union and national governments have developed and implemented different policies aimed to tackle the NEET situation. In this article, we try to identify and understand the most relevant barriers that keep vulnerable people as NEETs. We focused on youth as being at the highest risk of becoming NEETs: migrant women aged 25–29. By using semi-structured interviews and focus groups with key stakeholders and NEETs in the Spanish region of Murcia, we collected their views on and experiences with different programs and strategies. We conclude that this group is exposed to additional barriers due to the intersectionality of their characteristics. There are structural and contextual aspects, such as motherhood, a lack of social networks, or not knowing the language, which NEET policies do not address. We highlight the need of (i) improving the adaptiveness of relevant policies by being tailored to specific problems NEETs face, (ii) expanding the focus of NEET policies, and (iii) including the regional perspective in NEET policy design. In our comprehensive approach, we stress that the NEET policy alone cannot solve the NEET problem.

The coast of Chile has been exposed to marine submersion events from storm surges, tsunamis and flooding due to heavy rains. We present evidence of these events using sedimentary records that cover the last 1000 years in the Pachingo wetland. Two sediment cores were analyzed for granulometry, XRF, pollen, diatoms and TOC. Three extreme events produced by marine submersion and three by pluvial flooding during El Niño episodes were identified. Geochronology was determined using a conventional dating method using 14C, 210Pbxs and 137Cs). The older marine event (E1) was heavier, identified by a coarser grain size, high content of seashells, greater amount of gravel and the presence of two rip-up clasts, which seems to fit with the tsunami of 1420 Cal AD. The other two events (E3 and E5) may correspond to the 1922 (E3) tsunami and the 1984 (E5) storm waves, corroborated with a nearshore wave simulation model for this period (SWAM). On the other hand, the three flood events (E2, E4, E6) all occurred during episodes of El Niño in 1997 (E6), 1957 (E4) and 1600 (E6), represented by layers of fine-grain sands and wood charcoal remains.

The study addresses the reality of gender violence in women with functional diversity (dis-ability). It aims to make visible the situation of women with functional diversity who face gender violence in multiple ways, analyze their situation, needs and obstacles to learn how they face in the course of their lives both within the private sphere and in The public one. The combination of these two constructs conditions them and limits them to greater dependence and social invisibility. A qualitative methodology is carried out through discussion groups (G.D) with women with physical and sensory D.F. Empowerment is a key aspect for women with functional diversity to become aware of the relevance of their lives and thus have the management of their stories and life experiences.

A partir de encuentros de saberes desde una investigación participante, se recorren diversos escenarios de adolescentes en dos regiones, Colombia y España, con el fin de analizar muchas de las actitudes, prejuicios y estereotipos que están inmersos en las realidades de jóvenes en ambos países. Para ello el presente trabajo presenta los diferentes escenarios sociales y culturales, y posteriormente tras el trabajo de campo etnográfico, desde entrevistas en profundidad, entrevistas semiestructuradas y grupos de discusión, se pretende reconocer un diálogo de saberes que vaya más allá de la realidad, aportando un espacio de reflexión y cambio en los escenarios donde se han realizado las investigaciones, con el objetivo de entablar en ambas realidades, similitudes de pareceres, símbolos y actitudes en las relaciones de género, además de las estrategias que aportan los y las jóvenes para mejorar estas relaciones en diferentes ámbitos socioeducativos, el escenario comunitario y la educación superior.

En este artículo se presentan diferentes organizaciones comunitarias del Estado de Tabasco, Sureste de México, que se originan tras procesos de resistencia de la explotación de sus recursos petroleros desde la segunda mitad del Siglo XX. A partir de una etnografía, se visibilizan las diferentes razones y propuestas vinculadas a procesos de resistencia comunitaria de población civil, campesina y en su mayoría, indígena, así como las razones por las que han sido criminalizadas sus acciones en pro de su desarrollo comunitario. Actualmente, su activismo continúa por las explotaciones petroleras y sus consecuencias de contaminación, las inundaciones con responsabilidad institucional en el manejo de presas, la violencia de género y en general, un desinterés de apoyar a la población indígena por vincularla con un partido político de oposición al gobierno del país. Desde el origen de estas resistencias, que han sido utilizados por diversos intereses, se presentan sus apuestas por una educación política comunitaria cada vez más autónoma, tanto de instituciones gubernamentales como de ONG y/o partidos políticos.

Este artículo aborda la relación existente entre la Antropología Social y sus disciplinas vecinas desde una aproximación que integra perspectivas diferentes. En primer lugar se analiza el marco universitario, prestando atención a los decretos que delimitan la Antropología Social en el ámbito de las Humanidades, Ciencias Sociales y Jurídicas. En segundo lugar se analizan las opiniones recogidas de una muestra de antropólogos en relación con el informe Presente y futuro de la Antropología Social y cultural española: a partir de las reflexiones sobre niveles de asociación científico-académica entre áreas de conocimiento. La parte final retoma la información anterior para elaborar la reflexión sobre la relación interdisciplinar, centrándose en los nexos de unión entre la Antropología Social y las disciplinas identificadas como más significativas.

To deal with gender violence in formal and informal educational facilities, strategies are required to identify violences and their symbols, to be close to a more anthropological view agreeing with cultural and social convergences. A unique characterization of the violence that makes visible different behaviors and gives conexion with an independent public recognition of private and public, household and community integrity is rejected. The complexity of the symbols that exist in many companies is accentuated, in this case experiences that have worked from a reflexive ethnography in multicultural and intercultural spaces confirm a need to incorporate a decolonization understanding of gender violence.

An electrochemical sensor is proposed to measure silicate concentration, in situ, in the ocean without any addition of liquid reagent. From the analytical principle to the laboratory prototype toward the first in situ, immersible sensor, the evolution of the mechanical design is presented and discussed. The developed in situ electronics were compared to the commercial potentiostat and gave promising results to detect low silicate signals with a limit of quantification of 1 μmol L−1.The flow rate of the pump appeared to be a crucial parameter in order to transfer the silicomolybdic complex formed from the “complexation cell” to the “detection cell” without dilution as well as to fill and rinse the whole circuit. The study of temperature effect revealed no influence on the electrochemical signal between ~7° and ~21°C. Finally the sensor was successfully deployed for the very first time on a mooring off Coquimbo, Chile and also integrated onto a PROVOR profiling float in the Mediterranean Sea off Villefranche-sur-Mer, France. The data collected and/or sent through satellite were in good agreement with the 2 reference samples and previously published values illustrating the great potential of this electrochemical sensor. A 7 days silicate time series from the mooring deployment off Chile is also presented.

A partir de una etnografía, se revisan las nociones migratorias de los pobladores de dos regiones pesqueras en el sureste de México: Arriaga, estado de Chiapas, en la Costa del Pacífico, y La Barra de San Pedro, estado de Tabasco, en la Costa del Golfo de México, así como sus identidades y tendencias. La costa de Arriaga se localiza en una región de ámbito pesquero y paso fronterizo hacia Estados Unidos; por su parte, La Barra de San Pedro ha sido un lugar receptor de población veracruzana desde 1980 y en la actualidad laboralmente activa en la pesquería artesanal de mediana altura, compartiendo un espacio marino con la explotación petrolera. Como territorios de economía pesquera, observamos realidades, migración y tendencias en jóvenes de familias de pescadores, quienes con identidades similares y diferencias regionales están revirtiendo en el futuro de la pesca las intenciones de que perdure esta actividad y sus necesidades migratorias.

Con el objetivo de reconstruir los cambios temporales de la productividad fitoplanctónica durante el pasado reciente, se han analizado los contenidos de carbono orgánico total, ópalo biogénico, "chlorins" y alquenonas en un testigo de sedimentos laminados recuperado de la Bahía Mejillones. Adicionalmente, los parámetros físicos medidos (contenido de agua, densidad seca, susceptibilidad magnética, rayos-X y escala de grises) contribuyeron a la caracterización de los sedimentos. El testigo recuperado con un sacatestigo de caja (Testigo 3; 23°03' S, 70°27' W; 80 m de profundidad de la columna de agua) registró una tasa de sedimentación de 0,18 cm año-1 (basada en mediciones de 210Pb). La extrapolación de esta tasa de sedimentación a la base del testigo da cuenta de una edad de ~223 años. Los sedimentos se caracterizaron por presentar una sucesión de láminas claras y oscuras de grosor milimétrico, que se diferencian tanto en sus propiedades físicas como en la composición. Así las láminas oscuras, de mayor densidad y menor contenido de agua, representarían períodos de mayor productividad fitoplanctónica mientras que las láminas claras, de menor densidad y mayor contenido de agua, reflejarían períodos de menor productividad, concordando con estudios previos. La buena preservación de las láminas, lajiusencia de estructuras asociadas a procesos de bioperturbación, y los altos valores del δ15N sedimentario ( = 11,37 %¿) sugieren que los niveles de oxígeno en el agua de fondo de la bahía han permanecido bajos durante el período de dos siglos de depositación de los sedimentos reportados aquí. Nuestro registro se divide en dos grandes intervalos de productividad: un intervalo de menor productividad fitoplanctónica, antes de AD 1820, asociado a condiciones relativamente más cálidas en al área de surgencia, y otro de mayor productividad y altamente variable, a partir de AD 1877, relacionado con condiciones relativamente más frías asociado a una intensificación de los vientos y de la surgencia costera. Nuestro trabajo sugiere que la productividad desde AD 1820 ha estado fuertemente condicionada por la producción primaria silícea, y que especialmente a partir de AD 1877 se habría acoplado una mayor producción primaria calcárea.We analyzed the contents of total organic carbon, biogenic opal, chlorins, and alkenones (as productivity proxies) from a laminated sediment core recovered within Bahía Mejillones, northern Chile, in order to reconstruct recent temporal changes in phytoplankton productivity. Physical parameters (water content, dry bulk density, magnetic susceptibility, X-radiography, and grey scale intensity) were also used to characterize the sediments. A sedimentation rate of 0.18 cm year¹ (based on 210Pb measurements) was determined for the core (Core 3; 23°03' S, 70°27' W), which was recovered with a box-corer (water column depth: 80 m). By extrapolating this sedimentation rate to the base of the core, it yielded a total age of ~223 years. The sediments were characterized by a succession of light and dark millimetre-thick laminae, which differed in both physical properties and composition; the denser dark laminae had less water content and represented periods of increased phytoplankton productivity, whereas the less dense, light laminae had higher water content and reflected less productive periods. The good preservation of the laminae^ the absence of structures associated with processes of bioturbation, and the high sedimentary δ15N values ( = 11.37 %o) suggest low dissolved oxygen levels in the bay's bottom water during the two centuries of sedimentary deposition reported herein. Our record is divided into two large productivity intervals: one prior to AD 1820, with lower phytoplankton productivity and relatively warmer conditions, and another from ~AD 1877 to the present, characterized by higher productivity, high variability, and relatively colder conditions, and accompanied by intensified winds favouring coastal upwelling. We suggest that the productivity of Mejillones Bay since AD 1820 has been strongly dependent on siliceous production and that calcareous primary production has increased since AD 1877.

We present a 100-year reconstruction of siliceous export production from sediments of the Puyuhuapi Channel (44° S, 70° W) in the Chilean fjords. We use accumulation rates and concentrations of diatoms and silicoflagellates, organic carbon (Corg) and biogenic opal (SiOPAL) as proxies of export production, and fluctuations in the contribution of freshwater diatoms as proxies of rainfall in the hinterland and river runoff. Box core sediments collected at two sites within the Puyuhuapi Channel were analyzed: Station 35 (at the head of the fjord; 56 m water depth) and Station 40 (in the middle of the Channel; 270 m water depth). Surface sedimentation rates were 0.75 cm yr-1 at Station 35 and 0.25 cm yr-1 at Station 40. SiOPAL content averaged ~ 4 % at both sites. Diatom accumulation rates as well as the contribution of freshwater diatoms were higher at the head of the fjord (1.59 10(10) valves m-2 yr-1 and 22 %, respectively) than in its middle (1.08 10(10) valves m_2 yr_1 and 14 %, respectively). Diatom abundances were two orders of magnitude higher than silicoflagellate contribution at both sites. In general, diatoms typical of high nutrient environments characterize the Puyuhuapi Channel sediments: at both sites, spores of the genus Chaetoceros dominated the diatom assemblage (> 40 % of total diatoms; spores of Chaetoceros radicans/cinctus, Ch. constrictus/vanheurcki, Ch. debilis and Ch. diadema). Downcore analysis reveals an overall increase in the production of siliceous microorganisms from the late 19th century to the early 1980s, and then a decrease until the late-1990s. We associate a decrease in freshwater diatom contribution since the mid-1970s which we associate with a concomitant decline in rainfall in the Chilean fjords. We suggest that this decline is related to the global atmospheric and oceanic warming of the past ~ 25 yearsSe presenta una reconstrucción de 100 años de la productividad silícea exportada en sedimentos del canal Puyuhuapi (44° S, 70° O) en los fiordos chilenos. Se utilizan las tasas de acumulación y las concentraciones de diatomeas y silicoflagelados, carbono orgánico (Corg) y sílice biogénico (SiOPAL) como indicadores de la producción exportada y las fluctuaciones en la contribución de diatomeas de agua dulce como indicadores de precipitación y descargas de ríos. Se analizaron muestras de sedimentos colectadas mediante un sacatestigo de caja en dos sitios en el canal Puyuhuapi: Estación 35 (ubicada en la cabeza del fiordo dentro del seno Ventisquero; 56 m de profundidad) y Estación 40 (en la mitad del canal; 270 m de profundidad de agua). Las tasas de sedimentación superficial fueron de 0,75 cm año-1 en la Estación 35 y 0,25 cm año-1 en la Estación 40. En ambos sitios el contenido promedio de SiOPAL fue de ~ 4 %. Las tasas de acumulación de diatomeas así como la contribución de diatomeas de agua dulce fueron más altas en la cabeza del fiordo (1,59 10(10) valvas m-2 año-1 y 22 %) que en la mitad de este (1,08 10(10) valvas m-2 año-1 y 14 % respectivamente). Las abundancias de diatomeas fueron dos órdenes de magnitud más altas que la contribución de silicoflagelados. En general, los sedimentos del canal Puyuhuapi son caracterizados por diatomeas típicas de ambientes de altos nutrientes: en ambos sitios, las esporas del género Chaetoceros dominan la asociación de diatomeas (> 40 % de la asociación total de diatomeas, esporas de Chaetoceros radicans/cinctus, Ch. constrictus/vanheurcki, Ch. debilis y Ch. diadema). En general se observa un aumento en la tasa de acumulación de microorganismos silíceos desde finales del siglo XIX hasta comienzos de 1980, y un descenso hacia finales de la década de 1990. Asociamos una disminución en la diatomeas, sílice biogénico y silicoflagelados hacia el presente, sugiriendo una reducción en la productividad. Esto es acompañado por una disminución en las diatomeas de agua dulce desde mediados de los años 1970, con una disminución concomitante en la precipitación en el área de los fiordos chilenos. Sugerimos que dicha disminución se relaciona con el calentamiento atmosférico y oceánico global de los últimos 25 años

Desde la antropología se presenta una etnografía realizada en escuelas unitarias, en contraste con una escuela urbana en un contexto de exclusión social en la región de Murcia. Se encontraron respuestas a la existencia de perfiles docentes que deben visibilizarse en la formación del profesorado, partiendo de las realidades educativas diversas que deben de ser analizadas en los grados de Infantil y Primaria. Mediante la etnografía reflexiva y una investigación acción participante en el Practicum, vivenciamos la necesidad de repensar la formación que se obtiene en el ámbito académico.

Bahía Concepción (36° Lat. S) es una de las zonas costeras más industrializadas de Chile con una gran actividad portuaria y pesquera. Presenta una alta productividad durante los períodos de surgencia, generando así una alta tasa de sedimentación de material particulado al cual se asocia el plomo (Pb). Este es un elemento altamente insoluble y reactivo con las partículas, siendo disponible rápidamente para las comunidades bentónicas. El principal objetivo de este estudio fue determinar la concentración de Pb en el material particulado y en el gusano Paraprionospio pinnata, organismo sedimentívoro descrito como representativo de la fauna bentónica de Bahía Concepción. Para ello, se instalaron 2 trampas de sedimentación por un período de 15 días, ubicadas a la entrada e interior de la bahía y se recolectaron organismos en 4 estaciones, en un transecto hacia la parte externa de la bahía. Este estudio se realizó en dos períodos del año, agosto de 1997 y marzo de 1998, que correspondieron a períodos de relajación e intensificación de la surgencia, respectivamente. La concentración de Pb en los poliquetos indica que estos responden a las variaciones en el flujo de Pb, siendo la ingestión de material particulado la principal vía de incorporación. De acuerdo a los patrones de circulación de la bahía se estimó un transporte neto de Pb particulado al interior de la bahía de ~10 mg cm-2 año-1Concepción Bay (36° Lat. S) is located in the heart of the most industrialized coastal zone of Chile, owing also an intense commercial and fishing harbor activity. Its high productivity, driven by the occurrence of seasonal coastal upwelling causes a high flux of particulate material to the sediments. Lead (Pb) is a highly insoluble, particle-reactive element and hence rapidly reaches benthic communities. The main objective of this study was to determine the Pb concentration in particulate material and also in the marine worm Paraprionospio pinnata, a deposit-feeder organism, being the most representative of benthic fauna of Concepción Bay. To do that, two traps were moored at the interior and at the entrance of bay for 15 days. The organism were collected in four stations along a transect through the outer bay. The samplings were carried out in two periods: August 1997 and March 1998 corresponding to relaxation and intensification of upwelling, respectively. The Pb concentrations in the polychaetes indicate that they are responding to Pb flux variations, being particulate material intake the main Pb input. According to the circulation patterns of the bay, a net Pb flux of ~10 mg cm-2 yr-1 was estimated

The current study describes the taxonomic and functional composition of metagenomic sequences obtained from a filamentous microbial mat isolated from the Comau fjord, located in the northernmost part of the Chilean Patagonia. The taxonomic composition of the microbial community showed a high proportion of members of the Gammaproteobacteria, including a high number of sequences that were recruited to the genomes of Moritella marina MP-1 and Colwelliapsycherythraea 34H, suggesting the presence of populations related to these two psychrophilic bacterial species. Functional analysis of the community indicated a high proportion of genes coding for the transport and metabolism of amino acids, as well as in energy production. Among the energy production functions, we found protein-coding genes for sulfate and nitrate reduction, both processes associated with Gammaproteobacteria-related sequences. This report provides the first examination of the taxonomic composition and genetic diversity associated with these conspicuous microbial mat communities and provides a framework for future microbial studies in the Comau fjord.

ambién nos contaron que habían encontrado gentes nacidas en tierras lejanas y que aunque hablaban en otras lenguas o con otro modo eran como hermanos, pues tenían sentimientos nobles y estaban dispuestos a darnos apoyo y acompañarnos … Así surgieron los lazos de lucha que hermanan y fortalecen, supimos de los acompañantes y aprendimos que la solidaridad es una fuerza que acerca a las gentes, acorta distancias y permite compartir penas, esfuerzos, logros, sueños y esperanzas… « Sentires», fragmento de relato inédito de Mario Domínguez RESUMEN A partir de una etnografía reflexiva, se prioriza sobre una participación política que ha trascendido hasta hoy por la organización y resistencia durante el conflicto armado interno de Guatemala. Es el caso de personas originarias de las Comunidades de Población en Resistencia, CPR, del Ixcán que han intervenido activamente en los procesos políticos de su municipio, debido en parte a una nueva identidad que emergió y creció con el lema «Resistencia para Avanzar». Apostaron por la organización y por una política activa que, con los Acuerdos de Paz y con proyectos estratégicos de descentralización política, participan en alcaldías municipales apoyándose en las experiencias de organización comunitaria aprendidas durante el conflicto armado interno. Así surgió una nueva cultura política que desde las masacres crea esperanza al pueblo indígena y a la sociedad. ABSTRACT On the basis of reflexive ethnography, the author focuses on the political participation that has taken place to date as a result of the organization and resistance during the internal armed conflict in Guatemala. This is the case of the people from the Ixcán CPRs who have actively intervened in the political processes in their municipality, partly due to their new identity that emerged and expanded as a result of the motto, «Progress through Resistance». They committed themselves to organization and active politics. As a result of the Peace Agreements and through the strategic projects of political decentralization, they participated in municipal town councils, using their experience in community organization from the internal armed conflict. And so a new political culture arose as result of the massacres, creating hope for indigenous people and society.