Microbial Diversity and Its Relationship to Physicochemical Characteristics of the Water in Two Extreme Acidic Pit Lakes from the Iberian Pyrite Belt (SW Spain)

The Iberian Pyrite Belt (IPB) hosts one of the world's largest accumulations of acidic mine wastes and pit lakes. The mineralogical and textural characteristics of the IPB ores have favored the oxidation and dissolution of metallic sulfides, mainly pyrite, and the subsequent formation of acidic mining drainages. This work reports the physical properties, hydrogeochemical characteristics, and microbial diversity of two pit lakes located in the IPB. Both pit lakes are acidic and showed high concentrations of sulfate and dissolved metals. Concentrations of sulfate and heavy metals were higher in the Nuestra Señora del Carmen lake (NSC) by one order of magnitude than in the Concepción (CN) lake. The hydrochemical characteristics of NSC were typical of acid mine waters and can be compared with other acidic environments. When compared to other IPB acidic pit lakes, the superficial water of CN is more diluted than that of any of the others due, probably, to the strong influence of runoff water. Both pit lakes showed chemical and thermal stratification with well defined chemoclines. One particular characteristic of NSC is that it has developed a chemocline very close to the surface (2 m depth). Microbial community composition of the water column was analyzed by 16S and 18S rRNA gene cloning and sequencing. The microorganisms detected in NSC were characteristic of acid mine drainage (AMD), including iron oxidizing bacteria (Leptospirillum, Acidithiobacillus ferrooxidans) and facultative iron reducing bacteria and archaea (Acidithiobacillus ferrooxidans, Acidiphilium, Actinobacteria, Acidimicrobiales, Ferroplasma) detected in the bottom layer. Diversity in CN was higher than in NSC. Microorganisms known from AMD systems (Acidiphilium, Acidobacteria and Ferrovum) and microorganisms never reported from AMD systems were identified. Taking into consideration the hydrochemical characteristics of these pit lakes and the spatial distribution of the identified microorganisms, a model explaining their geomicrobiology is advanced.This work has been supported by grants from the MINECO-Spain (www.mineco.gob.es) (CGL2011-22540 and CGL2009-11059), IGME 478 Grant (www.igme.es) and an ERC project ( erc.europa.eu) (250-350-IPBSL).Peer Reviewe

Comparative microbial ecology of the water column of an extreme acidic pit lake, Nuestra Señora del Carmen, and the Río Tinto basin (Iberian Pyrite Belt)

The Iberian Pyrite Belt, located in Southwestern Spain, represents one of the world’s largest accumulations of mine wastes and acid mine drainages. This study reports the comparative microbial ecology of the water column of Nuestra Señora del Carmen acid pit lake with the extreme acidic Río Tinto basin. The canonical correspondence analysis identified members of the Leptospirillum, Acidiphilium, Metallibacterium, Acidithiobacillus, Ferrimicrobium and Acidisphaera genera as the most representative microorganisms of both ecosystems. The presence of archaeal members is scarce in both systems. Only sequences clustering with the Thermoplasmata have been retrieved in the bottom layer of Nuestra Señora del Carmen and one station of Río Tinto. Although the photosynthetically active radiation values measured in this lake upper layer were low, they were sufficient to activate photosynthesis in acidophilic microorganisms. All identified photosynthetic microorganisms in Nuestra Señora del Carmen (members of the Chlamydomonas, Zygnemopsis and Klebsormidium genera) are major members of the photosynthetic eukaryotic community characterized in Río Tinto basin. This study demonstrates a close relationship between the microbial diversity of Nuestra Señora del Carmen pit lake and the diversity detected in the Río Tinto basin, which underlain the influence of the shared mineral substrates in the microbial ecology of these ecosystems. [Int Microbiol 2014; 17(4):225-233]Keywords: iron cycle · acidic pit lakes · acidophilic microorganisms · Río Tinto · Iberian Pyrite Bel

A Case Study of Geometric Modelling via 3-D Point Interpolation for the Bathymetry of the Rabasa Lakes (Alicante, Spain)

The interpolation of points by means of Information Technology programs appears as a technical tool of some relevancy in the hydrogeology in general and in the study of the humid zones in particular. Our approach has been the determination of the 3-D geometry of the humid zones of major depth of the Rabasa Lakes. To estimate the topography of the lake bed, we proceed to acquire information in the field by means of sonar and GPS equipment. A total of 335 points were measured both on the perimeter and in the lake bed. In a second stage, this information was used in a kriging program to obtain the bathymetry of the wetland. This methodology is demonstrated as one of the most reliable and cost-efficient for the 3-D analysis of this type of water masses. The bathymetric study of the zone allows us to characterize the mid- and long-term hydrological evolution of the lakes by means of depth-area-volume curves

The Interactive Role of Hydrocarbon Seeps, Hydrothermal Vents and Intermediate Antarctic/MediterraneanWater Masses on the Distribution of Some Vulnerable Deep-Sea Habitats in Mid Latitude NE Atlantic Ocean

In this work, we integrate five case studies harboring vulnerable deep-sea benthic habitats in different geological settings from mid latitude NE Atlantic Ocean (24–42º N). Data and images of specific deep-sea habitats were acquired with Remoted Operated Vehicle (ROV) sensors (temperature, salinity, potential density, O2, CO2, and CH4). Besides documenting some key vulnerable deep-sea habitats, this study shows that the distribution of some deep-sea coral aggregations (including scleractinians, gorgonians, and antipatharians), deep-sea sponge aggregations and other deep-sea habitats are influenced by water masses’ properties. Our data support that the distribution of scleractinian reefs and aggregations of other deep-sea corals, from subtropical to north Atlantic could be dependent of the latitudinal extents of the Antarctic IntermediateWaters (AAIW) and the Mediterranean Out- flow Waters (MOW). Otherwise, the distribution of some vulnerable deep-sea habitats is influenced, at the local scale, by active hydrocarbon seeps (Gulf of Cádiz) and hydrothermal vents (El Hierro, Canary Island). The co-occurrence of deep-sea corals and chemosynthesis-based communities has been identified in methane seeps of the Gulf of Cádiz. Extensive beds of living deep-sea mussels (Bathymodiolus mauritanicus) and other chemosymbiotic bivalves occur closely to deep-sea coral aggregations (e.g., gorgonians, black corals) that colonize methane-derived authigenic carbonates

INFORME CIENTÍFICO – TÉCNICO de la Campaña SUBVENT1

Memoria del Informe Cintífico-Técnico de la campaña oceanográfica SUBVENT-1.Anexos de operatividad y de las distintas técnicas utilizados a lo largo de la misma.La campaña SUBVENT1-0913 se ha realizado a lo largo del talud inferior del margen continental de las Islas Canarias, área que también es conocida en la literatura como Cuenca Canaria. Esta zona se caracteriza por la presencia de una serie de estructuras geológicas recientes, así se encuentran la parte distal de los depósitos de debris procedentes de las avalanchas volcánicas generadas desde las Islas Canarias, a favor de la pendiente y probablemente en relación con episodios eruptivos. En la parte meridional se encuentra además un conjunto de montes submarinos, de diversa entidad, de origen volcánico y, en general, aparece todo un conjunto de montículos con desniveles comprendidos entre 30 y 300 m que han constituido el principal objetivo de esta campaña. Así mismo, en este sector existen numerosos escarpes lineales de orientación subparalela a la del propio talud a los que se encuentran asociados en ocasiones los citados montículos. La adquisición de nuevos datos geofísicos y el muestreo llevado a cabo durante la campaña permitirá conocer mejor el origen de estos montículos y el proceso de emisión que los ha generado. Por otro lado, el conocimiento de las relaciones entre los sedimentos de debris y hemipelágicos junto con los asociados a las posibles emisiones de la zona permitirá conocer no sólo la evolución sedimentaria de este margen, sino establecer los episodios de emisión que generaron los montículos y conocer sus patrones de crecimiento. Así mismo, se podrá evaluar la tasa de sedimentación de la zona y el papel de la masa de agua de fondo antártica (AABW) en esta evolución.The SUBVENT1-0913 cruise has been carried out along the lower slope of the continental margin of the Canary Islands. This area is characterized by the presence of several recent geological structures. Among these are the distal parts of the volcano-clastics debris deposits originated by volcanic avalanches of the Canary Islands, transported by gravity along the slope and probably related in origin to eruptive episodes. In the southern part, numerous and different reliefs (seamounts, hills or mounds) of volcanic origin occur. The most frequents features display heights between 30 and 300 m and they have constituted one of the main aims of this survey. Moreover, in this sector there are several subparallel linear scarps with similar directions to the slope trend that could be associated with the aforementioned mounds. The acquisition of new geophysical data and samples during this campaign will allow a better understanding of the origin of these mounds and the emission processes that have generated them. On the other hand, the knowledge of the relationships between debris and hemipelagic sediments together with those associated with possible venting processes in the area, will reveal not only the sedimentary evolution of this margin, but also to establish emission episodes generating mounds and to know their growth patterns. Furthermore, it would be possible to evaluate the sedimentation rate in the area and the role played by the Antarctic Bottom Water (AABW) mass on this process.Plan Nacional de I+D, Ministerio de Economía y Competitividad. Investigación fundamental no Orientada. Proyecto de Investigación Coordinado SUBVENT “Emisiones submarinas de fluidos en los márgenes continentales de las Islas Canarias y del Golfo de Cádiz: Análisis comparativo de las construcciones asociadas” (CGL2012‐39524‐C02). Acción Complementaria EXARCAN “Trabajos científico-técnicos para la preparación, presentación y defensa de las propuestas de España ante Naciones Unidas para la Extensión de la Plataforma Continental de las Islas Canarias y Galicia” (CTM2010-09496-E)

Multidisciplinary Scientific Cruise to the Northern Mid-Atlantic Ridge and Azores Archipelago

This work presents the preliminary result of the multidisciplinary cruise EXPLOSEA2 surveying the northern Mid-Atlantic Ridge and Azores Archipelago from 46 300 N to 38 300 N aboard the R/V Sarmiento de Gamboa and ROV Luso over 54 days (June 11 to July 27, 2019). In this cruise report, we detail the geophysical, hydrographic, geological, oceanographic, ecological, and microbiological data acquired and a brief of main findings. The cruise addressed the exploration and comprehensive characterization of venting sites, including the water column, the sediments and rocks that host the hydrothermal activity, and the associated mineralizations, biology, and microbiology. Deep hydrothermal chimneys and massive sulfide deposits (up 3,000 m in depth) within the Moytirra hydrothermal active field were identified on slopes that had not been explored previously. Another striking finding made during the EXPLOSEA2 cruise was the field of carbonate chimneys named the “Magallanes-Elcano” field, a potentially relict ultramafic-hosted hydrothermal site sourced by abiotic methane. This field is related to a serpentinite and gabbro rock outcropping on a dome-shaped massif named the “Iberian Massif.” An outstanding finding of the EXPLOSEA2 survey was the identification of the first garden of soft corals growing after active submarine eruptions were reported in the Azores Archipelago composed by a high density of soft corals the suborder Alcyoniina at the summit and flanks of a recent volcanic cone at 160 m water depth developed during the 1957–1958 eruption of Capelinhos. Several cold-water coral habitats formed by colonial scleractinians (e.g., Lophelia pertusa and Madrepora oculata), coral gardens composed of mixed assemblages of black corals (Leiopathes sp.), and octocorals and dense aggregations of the glass sponge Pheronema carpenteri that may be classified as vulnerable marine ecosystems (VMEs) have been discovered during the EXPLOSEA2 cruise along the northern Mid-Atlantic Ridge. This work reveals the importance of multidisciplinary surveys to the knowledge of deep-sea environments

Comparative microbial ecology of the water column of an extreme acidic pit lake, Nuestra Señora del Carmen, and the Río Tinto basin (Iberian Pyrite Belt)

All rights reserved. The Iberian Pyrite Belt, located in Southwestern Spain, represents one of the world’s largest accumulations of mine wastes and acid mine drainages. This study reports the comparative microbial ecology of the water column of Nuestra Señora del Carmen acid pit lake with the extreme acidic Río Tinto basin. The canonical correspondence analysis identified members of the Leptospirillum, Acidiphilium, Metallibacterium, Acidithiobacillus, Ferrimicrobium and Acidisphaera genera as the most representative microorganisms of both ecosystems. The presence of archaeal members is scarce in both systems. Only sequences clustering with the Thermoplasmata have been retrieved in the bottom layer of Nuestra Señora del Carmen and one station of Río Tinto. Although the photosynthetically active radiation values measured in this lake upper layer were low, they were sufficient to activate photosynthesis in acidophilic microorganisms. All identified photosynthetic microorganisms in Nuestra Señora del Carmen (members of the Chlamydomonas, Zygnemopsis and Klebsormidium genera) are major members of the photosynthetic eukaryotic community characterized in Río Tinto basin. This study demonstrates a close relationship between the microbial diversity of Nuestra Señora del Carmen pit lake and the diversity detected in the Río Tinto basin, which underlain the influence of the shared mineral substrates in the microbial ecology of these ecosystems.This work has been supported by grants CGL2011-22540 and CGL2009-11059 from the MINECO, Grant 478 from IGME and grant 250-350-IPBSL from ERC.Peer Reviewe

Changes in stratification and iron redox cycle of an acidic pit lake in relation with climatic factors and physical processes

Nuestra Señora del Carmen (NSC) mine pit located in the northwest of Huelva province in the Iberian Pyrite Belt has been entirely flooded for several decades. The pit lake dimensions are 110 m×80 m, with a depth of 34 m and a volume of 79,500 m3. Lake water is acidic (average pH 2.7) with high concentrations of sulfate (8.5 g/L), magnesium (1.0 g/L) and metals (Fe 760 mg/L, Al 230 mg/L, Mn 88 mg/L and Cu 29 mg/L). As with the majority of mining lakes of the Iberian Pyrite Belt, this lake develops chemical stratification (meromictic lake) but unlike the rest, it has occasionally showed circulation throughout the entire water column at the beginning of some winters, displaying total homogenization (holomictic lake). The lake regains chemical stratification during periods of high precipitation due to freshwater runoff contribution from the basin (ectogenic meromixis). Furthermore, another unusual period of mixing was observed in the summer period. Evapoconcentration of the warmer upper layer has been identified as the reason for the chemical destabilization observed in the water column. This work presents the processes (evapoconcentration), parameters (temperature and electric conductivity) and climatic factors (runoff, precipitation and wind) that influence the development of chemical stratification or mixing of the water column in the lakeInstituto Geológico y Minero de España, Españ

Evolución climática durante el último siglo (1904-2002) en el Parque Nacional de las Tablas de Daimiel (Ciudad Real)

Las Tablas de Daimiel National Park (Ciudad Real, central Spain) is a very delicate wet/and that during the last century has experienced noticeable human-induced modifications. In order to understand the relations among climate, environment dynamics and human activity ;n this area, detailed analyses of meteorological series are required. Analysis of meteorological series corresponding to nine weather stations close to the Las Tablas de Daimiel National Park allows the reconstruction of regional climate for the 1904-2002 period. Four periods have been identified based on temperature records: 1904-1937, cold; 1938-1958, warm; 1959-1990, cold; 1991-2002, warm. Other four periods are identified considering rainfall variability: 1904-1954, dry; 1955- 1979, wet; 1980-1995, dry; 1996-2002, wet. A comparison of the climatic series to the main hydrological events reveals that there is no clear relationship between climate evolution and hydrology. Consequently, we argue that the human control over the environment evolution for the last 50 years has been more significant than the climatic and endogenic controls

Cambios en el almacenamiento de C en el Parque Nacional de Las Tablas de Daimiel (PNTD) en los últimos 1000 años

El Parque Nacional de Las Tablas de Daimiel ha sufrido muchas modificaciones a lo largo de su historia, tanto naturales como antrópicas y éstas han afectado de manera diversa al almacenamiento de carbono en el mismo. Para estudiar estas variaciones se ha realizado un análisis del registro sedimentario y de datos históricos de la zona. El registro sedimentario se estudió a partir del sondeo Cigüela 4 al que se le ha realizado un muestreo sistemático de alta resolución (0.7 cm de grosor medio) para analizar su geoquímica y su contenido polínico. Al analizar todos los datos hemos visto que los cambios naturales (asociados al clima) poseen mayores rangos de variación que los antrópicos, no muestran relación con la concentración de CO2 atmosférico y presentan una ciclicidad natural con una amortiguación rápida (décadas) de las variaciones. Sin embargo los impactos antrópicos dependen de la proximidad del impacto y la intensidad del mismo; así el cambio de usos producido a mediados del siglo XIX debido a la desamortización fue un impacto indirecto, de intensidad media y el medio fue capaz de recuperar los valores de almacenamiento normales en menos de 50 años. Sin embargo los episodios de desecación y sobreexplotación del acuífero que alimentaba el Parque Nacional (segunda mitad del siglo XX) fueron impactos directos de alta intensidad, durante los cuales la rápida pérdida de superficie inundada y la salinización del medio, causó una drástica pérdida en la capacidad del ecosistema para almacenar C, de la cual no parece que el ecosistema sea capaz de recuperarse de manera natural. [ABSTRACT] Las Tablas de Daimiel National Park has suffered too many modifications throughout its history, natural as well as anthropic, which have affected the carbon storage in different ways. The study of those variations has been carried out by the analysis of sedimentary record and historical data. The sedimentary record has been studied from the core Cigüela 4. It was sampled with a systematic high resolution method (0.7 cm thickness average) to analyze geochemistry and pollen. The analysis of all data shows that the natural changes (engaged with the climate) have more variation ranges than the anthropic ones, are directly related with the climate and not with the concentration of the atmospheric CO2, showing a natural cyclicity with a fast mitigation (decades) of the variations. In the other hand the anthropogenic impacts depend on the proximity and intensity of the impact. The usage changes produced during the second half of the 19th century were an indirect impact with medium intensity. The environment had the capacity to recover the values of a normal storage in less than 50 years. Nevertheless the dissication and overexploitation of the groundwater (second half of 20th century) were direct and high intensity impacts. These impacts caused a fast lost of the water table and the salinization of the environment. Due to that the ecosystem lost capacity to storage C. The recovering of the normal values by a natural way is difficult now