Current research areas

Home Curriculum Main Publications Research areas Conferences Infrastructure
Multimedia



Easter Island (Chile) Lake Chungará (Chile)  Montcortés Lake (Spain)  Lake Sanabria (Spain) Lake Blau (Andorra) Issyk-Kul Lake (Rep. Kyrgyzstan) KaraBogazGol (Rep. Turkmenistan)

Easter Island (Chile)

ir arribair arriba

Main goal:

- To obtain a high-resolution reconstruction of the El Niño - Southern Oscillation phenomena for the last 30,000 cal. years BP.

We have conducted two coring campaigns (2006 and 2008) and we cored the three main lacustrine ecosystems present in the island:

Rano Raraku:

We recovered 8 cores up to 14 m long, following an approximately north - south transect. These cores allowed us to obtain a composite log of 19.60 m which covers the last 34,000 cal. years BP.

 Rano Aroi:

We drilled two cores up to 16 m long using a piston core and two cores up to 4.20 m long using a Russian corer. The preliminary chronological framework of this cores suggests that the uppermost 14 m of the sedimentary infill of this lake records the last ca. 70,000 cal. years BP, with an important gap between ca. 10,000 and ca. 35,000 cal. years BP.

Rano Kao:

We cored one of the mat floating in the lake and a 4.20 m core was recovered employing a Russian corer. We hope to be able to characterize the climatic and environmental evolution of the island for the last 2,000 years.

The recovered cores have been studied using a wide range of techniques such as facies analyses, physical properties (magnetic susceptibility, p-wave and gamma-density) electron microscope (SEM and TEM), X-Ray Fluorescence, X-Ray diffraction, elemental geochemistry (TOC, TC, TS, TN), stable isotopes on bulk samples (d15N and d13C) and on cellulose (d13C and d18O) and biological content (pollen and spores, diatoms and crysophyceans). The chronological framework of these sequences have been built employing more than 35 AMS 14C dates performed at the Poznan Radiocarbon Laboratory.

The research team is composed by Alberto Sáez, Núria Cañellas and Juan José Pueyo (UB), Blas L. Valero-Garcés and Ana Moreno (IPE-CSIC), Sergi Pla (CEAB-CSIC), Valentí Rull (IBB-CSIC), Roberto Bao (UdC), and Armand Hernández and Olga Margalef (ICTJA-CSIC).

This research is being funded by the Spanish Science Ministry through the research projects "Fenómenos extremos en el registro sedimentario de lagos en contexto volcánico-hidrotermal activo (LAVOLTER)" CGL2004-00683 (2004 - 2007) and "Reconstrucción paleoclimática de alta resolución desde el Último Máximo Glaciar basada en indicadores geoquímicos y biológicos de lagos andinos y del océano Pacífico (GEOBILA)" CGL-2007-60932/BTE (2008 - 2010).

The main results have been published in:

- Sáez, A., Valero-Garcés, B.L., Giralt, S., Moreno, A., Bao, R., Pueyo, J.J., Hernández, A. and  Casas, D. 2009. Glacial to Holocene climate changes in the SE Pacific. The Raraku Lake sedimentary record (Easter Island, 27º S). Quaternary Science Reviews, 28: 2743-2759 [1.9 MB]

- Rull, V., Cañellas-Boltà, N., Sáez, A., Giralt, S., Pla, S. and Margalef, O. 2010. Paleoecology of Easter Island: evidence and uncertainties. Earth Science Reviews, 99:50-60 [616 KB]

Furthermore, the first results have been presented in a number of congresses:

- Sáez, A, Giralt, S., Valero-Garcés, B.L., Moreno, A., Bao, R., Pueyo, J.J. & Hernández, A. Glacial to Holocene climate changes in Easter Island (SE Pacific, 27º S). EGU General Assembly. Vienna, Austria

- Giralt, S.; Valero-Garcés, B..; Moreno, A.; Hernández, A.; Sáez, A.; Herrera, C.; José Pueyo, J.J.; Bao, R.; González-Sampériz, P. 2006. A role for climate change in the Easter Island culture collapse? A high-resolution multi-proxy study of the sedimentary infill of the Rano-Raraku and Rano-Aroi lacustrine ecosystems. Holocene Climatic Variability (HOLIVAR 2006). London (UK).

- Valero-Garcés, B..; Giralt, S.; Moreno, A.; Hernández, A.; Sáez, A.; Herrera, C.; Pueyo, J.J.; Bao, R.; González-Sampériz, P. 2006. Paleohydrological Changes in Rapa Nui (27ºS) During the Last Millennia Reconstructed from Rano Raraku and Rano Aroi Lakes. 10th International Paleolimnology Symposium. Duluth, USA.

- Sáez, A., Giralt, S., Klosowska, B., Valero-Garcés, B., Moreno, A., Hernández, A., Herrera, C., Pueyo, J.J., Bao, R., González-Samperiz, P., Casas, D. & Fernández-Turiel, J.L. 2007. Hydrological and sedimentary changes in Rano Raraku lake (Easter Island, 27ºS) for the last 33,000 years. 4th International Limnogeology Congress (ILIC-4). Barcelona, Spain.

- Klosowska, B., Pueyo, J.J., Giralt, S., Sáez, A., Moreno, A., Valero-Garcés, B., Bao, R. & Hernández, A. 2007. A 33 000 years cal BP paleoenvironmental record from Easter Island based on stable isotope analysis of lake sediment cellulose. 4th International Limnogeology Congress (ILIC-4). Barcelona, Spain.

- Moreno, A., Valero-Garcés, B.L., Sáez, A., Giralt, S., Klosowska, B., Hernández, A., Pueyo, J.J. & Bao, R. 2007. The X-Ray Fluorescence core scanner as a very useful proxy to infer paleoenvironmental variability: the study of lake cores from Easter Island. 4th International Limnogeology Congress (ILIC-4). Barcelona, Spain. 

Lake Chungará (Chile)

Main goal:

- To gain insights on the evolution of the El Niño - Southern Oscillation for the last 15,000 cal. years BP.

- To highlight the possible relationships (if any) between ENSO and other climate forcings, like solar activity, for the Late Glacial and Holocene periods.

In November 2002 we conducted an extensive coring campaign and we retrieved 15 long cores (up to 8 m long) using a Kullemberg coring system from the LRC (Minnesota, USA).

The research team is composed by Alberto Sáez and Juan José Pueyo (UB), Blas L. Valero-Garcés and Ana Moreno (IPE-CSIC), Sergi Pla (CEAB-CSIC), Roberto Bao (UdC), and Armand Hernández (ICTJA-CSIC).

These cores have been studied using a multiproxy approach: facies analyses, physical properties such as magnetic susceptibility, p-wave and gamma-density, electron microscope (SEM and TEM), X-Ray Fluorescence, X-Ray diffraction, elemental geochemistry (TOC, TC, TS, TN), stable isotopes on bulk samples (d18O, d15N and d13C), on carbonates (d13C and d18O), on the silica of the diatom frustules (d18O) and on the proteines contained in the diatoms (d13C) and biological content (pollen and spores, ostracods, diatoms and molluscs). The chronological framework of these sequences have been built employing 17 AMS 14C dates performed at the Poznan Radiocarbon Laboratory

This research is being funded by the Spanish Science Ministry through the research projects "Orígen de los solutos y evolución paleohidrológica en sistemas lacustres cuaternarios con influencia hidrotermal; Altiplano de los Andes Centrales (ANDESTER) " BTE-2001-3225 (2001 - 2004), Fenómenos extremos en el registro sedimentario de lagos en contexto volcánico-hidrotermal activo (LAVOLTER)" CGL2004-00683 (2004 - 2007) and "Reconstrucción paleoclimática de alta resolución desde el Último Máximo Glaciar basada en indicadores geoquímicos y biológicos de lagos andinos y del océano Pacífico (GEOBILA)" CGL-2007-60932/BTE (2008 - 2010).

Up to the present, the works that summarize the main results are:

- Sáez, A., Valero-Garcés, B.L., Moreno, A., Bao, R., Pueyo, J.J., González-Sampériz, P., Giralt, S., Taberner, C., Herrera, C., and Gibert, R.O. 2007. Lacustrine Sedimentation in Active Volcanic Settings: The Late Quaternary Depositional Evolution of Lake Chungará (Northern Chile). Sedimentology, 54: 1191-1222. [1.8 MB]

- Moreno, A., Giralt, S., Valero-Garcés, B., Sáez, A., Bao, R., Prego, R., Pueyo, J.J., González-Sampériz, P. and Taberner, C. 2007. A 13 kyr high-resolution record from the tropical Andes: The Chungara Lake sequence (18 °S, northern Chilean Altiplano). Quaternary International, 161: 4-21. [1.7 MB]

- Giralt, S., Moreno, A., Valero-Garcés, B., Sáez, A., Bao, R., Prego, R., Pueyo, J.J., González-Sampériz, P. and Taberner, C. 2008. A statistical approach to disentangle environmental forcings in a lacustrine record: the Lago Chungará case (Chilean Altiplano). Journal of Paleolimnology, 40:195-215. [701 KB]

- Hernández, A., Bao, R., Giralt, S., Leng, M.J., Barker, P.A., Sáez, A., Pueyo, J.J., Moreno, A., Valero-Garcés, B.L., & Sloane, H.J. 2008. Oxygen isotopes in diatom silica: The palaeohydrological evolution of Lago Chungará (northern Chilean Altiplano) during Late Glacial-Early Holocene. Journal of Quaternary Science, 23: 351-363. [2.1 MB]

-  Hernández, A., Giralt, S., Bao, R., Sáez, A., Leng, M.J. & Baker, P.A. 2010. ENSO and solar activity signals from oxygen isotopes in diatom silica during late glacial-Holocene transition in Central Andes (18ºS). Journal of Paleolimnogeology, 44: 413-429. [796 KB]

-  Hernández, A., Bao, R., Giralt, S., Baker, P.A., Leng, M.J., Sloane, H.J. & Sáez, A. 2011. Biogeochemical processes controlling oxygen and carbon isotopes of diatom silica in Late Glacial to Holocene lacustrine rhythmites. Palaeogeography, Palaeoclimatology, Palaeoecology, 299: 413-425. [1.1 MB]

Lake Montcortés (Spain)

Main goal:

- To obtain a detailed reconstruction of the impacts of the North Atlantic Oscillation through the Holocene.

In 2004, an extensive coring campaign in eight Spanish lakes allowed us to recover more than 200 m of lacustrine sediments (more details of this coring campaign are available at the Limnogeology and Global Change research group). We recovered 4 Kullemberg cores up to 8 m long.

The research team is composed by Blas L. Valero-Garcés, Ana Moreno, Penélope González-Sampériz, Mayte Rico and Pablo Corella (IPE-CSIC), Sergi Pla (CEAB-CSIC), Roberto Bao (UdC), Valentí Rull (IBB-CSIC) and Teresa Vegas-Villarrúbia (UB).

This research is being funded by the Spanish Science Ministry through the research projects "Variabilidad climática y su impacto en la Península Ibérica desde el último máximo glacial: correlación de registros continentales y marinos e implicaciones para el entendimiento del clima presente y futuro (LIMNOCLIBER)" REN2003-09130-C02-02/CLI (2003 - 2006) and "Cambios climáticos rápidos en la Península Ibérica basados en calibración de indicadores, series instrumentales largas y análisis de alta resolución de registros terrestres y marinos (CALIBRE)" CGL2006-13327-C04/CLI (2006 - 2009).

The first set of preliminary results are now being under elaboration in order to publish them in a peer-review journal:

- Corella, J.P., Valero-Garcés, B.L., Moreno, A., Morellón, M., Rull, V., Giralt, S., Rico, M.T. and Sanz-Pérez, A. 2010. Sedimentary evolution and palaeohydrology of karstic, meromictic Montcortés Lake (Spanish Pre-Pyrenees) during the last 6,000 years. Journal of Paleolimnology. doi: 10.1007/s10933-010-9443-3 [899 KB]

- Rull, V., González-Sampériz, P., Valero-Garcés, B.L., Corella, J.P., Morellón, M. and Giralt, S. 2010. Vegetation changes in the southern Pyrenean flank during the last millennium in relation to climate and human activities: the Montcortès lacustrine record. Journal of Paleolimnogeology. doi: 10.1007/s10933-010-9444-2 [741 KB]

These preliminary results have also been presented in:

- Corella, J.P., Valero-Garcés, B.L., Moreno, A., Giralt, S., Morellón, M., González-Sampériz, P., Rico, M.T. 2008. Evolución sedimentaria durante el Holoceno de un lago kárstico del Prepirineo: el lago de Montcortés (Lleida). VII Congreso Geológico de España, Las Palmas de Gran Canaria, Spain.

Lake Sanabria (Spain)

Main goal:

- To obtain quantitative reconstructions of precipitation and/or temperature for the last 200 years through the calibration of the geochemical composition of the sediments with the available instrumental limnological and meteorological data.

In 2007 we obtained 10 short gravity cores (up to 62 cm long) which have been characterized by x-ray diffraction, x-ray fluorescence, elemental geochemistry (TN, TS, TOC and TC) and biological content (chyronomids and diatoms). Two of these cores have been dated using 210Pb and 137Cs.

The research team is composed by Blas L. Valero-Garcés, Ana Moreno, Penélope González-Sampériz, Mayte Rico and Mario Morellón (IPE-CSIC), Roberto Bao (UdC), Maria Rieradevall and Teresa Vegas-Villarrúbia (UB), and José Carlos Vega (Parque Natural Lago Sanabria).

This research is being funded by the Spanish Science Ministry through the research projects "Variabilidad climática y su impacto en la Península Ibérica desde el último máximo glacial: correlación de registros continentales y marinos e implicaciones para el entendimiento del clima presente y futuro (LIMNOCLIBER)" REN2003-09130-C02-02/CLI (2003 - 2006) and "Cambios climáticos rápidos en la Península Ibérica basados en calibración de indicadores, series instrumentales largas y análisis de alta resolución de registros terrestres y marinos (CALIBRE)" CGL2006-13327-C04/CLI (2006 - 2009).

The first preliminary results have been presented in:

- Rico, M., Giralt, S., Valero-Garcés, B.L., Vega, J.C., Moreno, A., Morellón, M. and González-Sampériz, P. 2009. Hacia una calibración del registro sedimentario lacustre y del registro instrumental: el lago de Sanabria. CLIMA EN ESPAÑA: PASADO, PRESENTE Y FUTURO Contribución a un informe de evaluación del cambio climático regional. Madrid (Spain).

Lake Blau (Andorra)

Main goal:

- To obtain a high-resolution environmental and climatic reconstruction for the last 1,000 years.

In summer 2005 we obtained 2 gravity cores 48 cm and 65 cm long. These cores have been characterized using a high temporal resolution multiproxy approach (pollen and spores, mineralogical composition, crysophytes and geochemistry). This multiproxy approach has been done in collaboration with Santiago Riera (UB), Josep Ma Palet and Ana Ejarque (ICAC), Sergi Pla and Lluís Camarero (CEAB-CSIC) and Armand Hernández (ICTJA-CSIC).

This research is funded by the research project "Ocupació del sòl i formes del paisatge de muntanya als Pirineus orientals de l'Antiguitat a l'Època medieval" (Andorra Government). Some results were presented in: 

- Giralt, S., Riera, S., Ejarque, A., Hernández, A. , Camarero, L., Altuna, M., Pla, S., Palet, J.M. 2006. Evolución paleoambiental de sectores altitudinales de los Pirineos orientales durante los ultimos 2000 años: cambios climáticos vs. actividad antrópica. El registro de Estany Blau (2400 m, vall del Madriu, Andorra). XIII Congreso de la Asociación Española de Limnología y el V Congreso Ibérico de Limnología. Barcelona, Spain.

Issyk-Kul Lake (Rep. Kyrgyzstan)

Main goal:

- To obtain a ultra-high environmental and climatic reconstruction for the last 4,000 cal. years BP.

Coring campaigns have been developed in 1998, 2001 and 2002. These cores have been characterized using a large set of proxies: magnetic susceptibility and other magnetic properties, thin sections, lithofacies, grain-size, x-ray diffraction, bulk geochemistry (TC, TOC, TC), x-ray fluorescence, pollen and spores, ostracods and stable isotopes on carbonates (d13C and d18O). The chronological framework is based on AMS 14C, 210Pb, 137Cs and carbonaceous particles. Detailed information of the main macro- and micro-lithofacies of some cores as well as the distribution of the most important lacustrine sedimentary processes is accesible in the webpage of the EU Copernicus project APELIK.

At present the research team is composed by Pere Anadón, Rosa Utrilla, Antonio Vazquez and Juan C. Larrasoaña (ICTJA-CSIC), Belén Rubio and Daniel Rey (UV), and Miriam Gómez (UB).

This research is being funded by the EU Copernicus project " Assessment and prognosis of environmental changes in Lake Issyk-Kul (Kyrgyzstan)" and by Spanish Science Ministry project "Multidisciplinary Research Consortium on Gradual and Abrupt Climate Changes and their Impact on the Environment (GRACCIE) CONSOLIDER-INGENIO".

The main results have been published in:

- Giralt, S., Julià, R. & Klerkx, J. 2001. Microbial biscuits of vaterite in Lake Issyk-Kul (Republic of Kyrgyzstan). Journal of Sedimentary Research , 71, 430-435. [707 KB]

- Giralt, S., Riera, S., Klerkx, J., Julià, R., Lignier, V., Beck, C., De Batist, M., & Kalugin, I. 2002. Recent Paleoenvironmental evolution of Lake Issyk-Kul. In: J. Klerkx & B. Imanackunov (Eds.) The Issyk-Kul Lake: Evaluation of Environmental State and Its Remediation. NATO ASI Series. Kluwer Academic Publishers: 125-146. [646 KB]

- De Batist, M., Klerkx, J., Imbo, Y., Giralt, S., Lignier, V., Beck, C., Delvaux, D., Vermeesch, P., Kalugin, I. & Abdrachmatov, K. 2002. Bathymetry and sedimentary environments of a large, high-altitude, tectonic lake: Lake Issyk-Kul, Kyrgyz Republic (Central Asia). In: J. Klerkx & B. Imanackunov (Eds.). The Issyk-Kul Lake: Evaluation of Environmental State and Its Remediation. NATO ASI Series. Kluwer Academic Publishers: 101-124. [1.3 MB]

- Giralt, S., Riera, S., Leroy, S., Buchaca, T., Klerkx, J., De Batist, M., Beck, C., Bobrov, V., Brennwald, M., Catalan, J., Gavshin, V., Julià, R., Kalugin, I., Kipfer, R., Lombardi, S., Matychenkov, V., Peeters,F., Podsetchine, V., Romanovsky, V.V., Sukhorukov, F., & Voltattorni, N. 2004. 1,000-years of environmental history of Lake Issyk-Kul. In: J.C.J. Nihoul, P.O. Zavialov, P.P. Micklin (Eds). Dying and Dead Seas: Climatic Versus Anthropic Causes. Kluwer Academic Publishers. NATO ASI SERIES, IV, Earth and Environmental Sciences, 36: 228-253. [2.1 MB]

- Brennwald, M. S., Peeters, F., Imboden, D. M., Giralt, S., Hofer, M., Livingstone, D. M., Klump, S., Strassmann, K. & Kipfer, R. 2004. Atmospheric noble gases in lake sediment pore water as proxies for environmental change. Geophysical Research Letters, 31, L04202, doi:10.1029/2003GL019153. [250 KB]

As well as in a number of scientific conferences:

- Giralt, S. 2003. Sedimentary processes in a tectonic lake (Issyk-Kul). BAIK-SED-2: International Workshop on sedimentary processes in large lakes. Ghent, Belgium.

- Giralt, S. 2003. Endogenic precipitation as environmental indicator (Issyk-Kul). BAIK-SED-2: International Workshop on sedimentary processes in large lakes. Ghent, Belgium.

- Giralt, S., Riera, S., Buchaca, T., Julià, R., Leroy, S., Catalan, J., Klerkx, J., De Batist, M., Kalugin, I., Matychenkov, V., & Romanovsky, V. 2003. 1000-yr environmental changes of Lake Issyk-Kul (Rep. Kyrgyzstan, Central Asia). ILIC3: 3rd International Limnogeology Congress. Tucson, USA.

- Giralt, S., Riera, S., Leroy, S., Buchaca, T., Klerkx, J., De Batist, M., Beck, C., Bobrov, V., Brennwald, M., Catalan, J., Gavshin, V., Julià, R., Kalugin, I., Kipfer, R., Lombardi, S., Matychenkov, V., Peeters, F., Podsetchine, V., Romanovsky, V.V., Sukhorukov, F., & Voltattorni, N. 2003. 1,000-years of environmental history of Lake Issyk-Kul. ARW - NATO Dying and Dead Seas. Liège, Belgium.

- Giralt S., Riera S., Julià, R. 2007. 1,800-years of water availability oscillations in Central Asia. I Congreso Nacional sobre Cambio Climático. Madrid, Spain.

-Giralt, S., Hernández, A., Sáez, A., Pueyo, J.J., Cañellas-Boltà, N. & Margalef, O. 2010. Late Holocene environmental reconstruction of Lake Issyk-Kul (Rep. Kyrgyzstan). European Geophysical Union (EGU), Vienna, Austria.

KaraBogaz-Gol - Caspian Sea ecosystem (Rep. Turkmenistan)

Main goal:

- To obtain an annual environmental and climatic reconstruction for the last 100 years.

We cored the bay in 1999 and we recovered 6 cores up 1 m long. These cores have been studied using a large set of techniques: thin sections, mineralogy, bulk geochemistry (major, minor and trace elements) and biological content (pollen and spores, and dynocysts). The chronological framework has been built using 210Pb and 137Cs.

At present, the research team is composed by Juan José Pueyo (UB), Joan-Albert Sanchez-Cabeza, Laval Liong Wee Kwong, Oxana Blinova and Iolanda Osvath (IAEA-Monaco). 

The main results of this research have been published in: 

- Giralt, S., Julià, R., Leroy, S. & Gasse, F. 2003. Cyclic water level oscillations of the KaraBogaz Gol Caspian Sea system. Earth and Planetary Science Letters, 212, 225-239. [1.0 MB]

 - Leroy, S. A. G., Marret, F., Giralt, S. & Bulatov S. A. 2006. Natural and anthropogenic rapid changes in the Kara-Bogaz Gol over the last two centuries by palynological analyses. Quaternary International, 150: 52-70. [1.1 MB]

as well as in a number of conferences: 

-  Giralt, S., Sánchez-Cabeza, J.A., Liong Wee Kwong, L., Blinova, O., Osvath, I. & Pueyo, J.J. 2009. Recent pollutant history of the KaraBogaz-Gol - Caspian Sea ecosystem (Rep. of Turkmenistan). EGU General Assembly. Vienna, Austria.

- Leroy, S.A.G., Marret, F., Giralt, S. & Bulatov, S.A. 2005. Natural and anthropogenic rapid changes in the Kara-Bogaz Gol over the last two centuries by palynological analyses. International Conference Rapid Sea level change a Caspian perspective. Rasht, Iran.