Browsing by Author "De Pol-Holz, Ricardo"
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- ItemChronology, stratigraphy and hydrological modelling of extensive wetlands and paleolakes in the hyperarid core of the Atacama Desert during the late quaternary(2018) Pfeiffer, Marco; Latorre H., Claudio; Santoro, Calogero M.; Gayo Hernández, Eugenia Monserrat; Rojas Ávila, Rodrigo; Laura Carrevedo, Maria; Mc Rostie Bustamante, Virginia Bernardita; Finstad, Kari M.; Heimsath, Arjun; Jungers, Matthew C.; De Pol-Holz, Ricardo; Amundson, Ronald
- ItemDust fluxes and iron fertilization in Holocene and Last Glacial Maximum climates(2015) Lambert, Fabrice; Tagliabue, Alessandro; Shaffer, Gary; Lamy, Frank; Winckler, Gisela; Farias, Laura; Gallardo, Laura; De Pol-Holz, Ricardo
- ItemHolocene tephrochronology around Cochrane (~47° S), southern Chile(2016) Stern, Charles R.; Moreno, Patricio I.; Henriquez, William I.; Villa Martinez, Rodrigo; Sagredo T., Esteban; Aravena, Juan Carlos; De Pol-Holz, Ricardo
- ItemInfluence of Glacier Melting and River Discharges on the Nutrient Distribution and DIC Recycling in the Southern Chilean Patagonia(2018) Vargas, Cristian A.; Antonio Cuevas, L.; Silva, Nelson; Gonzalez, Humberto E.; De Pol-Holz, Ricardo; Narvaez, Diego A.The Chilean Patagonia constitutes one of the most important and extensive fjord systems worldwide, therefore can be used as a natural laboratory to elucidate the pathway of both organic and inorganic matter in the receiving environment. In this study we use data collected during an intensive oceanographic cruise along the Magellan Strait into the Almirantazgo Fjord in southern Patagonia to evaluate how different sources of dissolved inorganic carbon (DIC) and recycling may impact particulate organic carbon (POC) C-13 and influence the nutrients and carbonate system spatial distribution. The carbonate system presented large spatial heterogeneity. The lowest total alkalinity and DIC were associated to freshwater dilution observed near melting glaciers. The C-13(DIC) analysis suggests that most DIC in the upper 50m depth was not derived from terrestrial organic matter remineralization. C-13-depleted riverine and ice-melting DIC influence the DIC pool along the study area, but due to that DIC concentration from rivers and glaciers is relatively low, atmospheric carbon contribution or biological processes seem to be more relevant. Intense undersaturation of CO2 was observed in high chlorophyll waters. Respired DIC coming from the bottom waters seems to be almost insignificant for the inorganic carbon pool and therefore do not impact significantly the stable carbon isotopic composition of dissolved organic carbon and POC in the upper 50m depth. Considering the combined effect of cold and low alkalinity waters due to ice melting, our results highlight the importance of these processes in determining corrosive waters for CaCO3 and local acidification processes associated to calving glacier in fjord ecosystems.
- ItemLoco or no Loco? Holocene Climatic Fluctuations, Human Demography, and Community Based Management of Coastal Resources in Northern Chile(2017) Santoro, Calogero M.; Gayo Hernández, Eugenia Monserrat; Carter, Chris; Standen, Vivien G.; Castro, Victoria; Valenzuela, Daniela; De Pol-Holz, Ricardo; Marquet, P. A. (Pablo A.); Latorre H., Claudio
- ItemMarine radiocarbon reservoir age along the chilean continental margin(2019) Merino-Campos, Victor; De Pol-Holz, Ricardo; Southon, John; Latorre H., Claudio; Collado-Fabbri, Silvana
- ItemRadiocarbon bomb-peak signal in tree-rings from the tropical Andes register low latitude atmospheric dynamics in the Southern Hemisphere(2021) Ancapichun, Santiago; De Pol-Holz, Ricardo; Christie, Duncan A.; Santos, Guaciara M.; Collado-Fabbri, Silvana; Garreaud, Rene; Lambert, Fabrice; Orfanoz-Cheuquelaf, Andrea; Rojas, Maisa; Southon, John; Turnbull, Jocelyn C.; Creasman, Pearce PaulSouth American tropical climate is strongly related to the tropical low-pressure belt associated with the South American monsoon system. Despite its central societal role as a modulating agent of rainfall in tropical South America, its long-term dynamical variability is still poorly understood. Here we combine a new (and world's highest) tree-ring C-14 record from the Altiplano plateau in the central Andes with other C-14 records from the Southern Hemisphere during the second half of the 20th century in order to elucidate the latitudinal gradients associated with the dissemination of the bomb C-14 signal. Our tree-ring C-14 record faithfully captured the bomb signal of the 1960's with an excellent match to atmospheric C-14 measured in NewZealand but with significant differences with a recent record from Southeast Brazil located at almost equal latitude. These results imply that the spreading of the bomb signal throughout the Southern Hemisphere was a complex process that depended on atmospheric dynamics and surface topography generating reversals on the expected north-south gradient in certain years. We applied air-parcelmodeling based on climate data to disentangle their different geographical provenances and their preformed (reservoir affected) radiocarbon content. We found that air parcel trajectories arriving at the Altiplano during the bomb period were sourced i) from the boundary layer in contact with the Pacific Ocean (41%), ii) fromthe upper troposphere (air above the boundary layer, with no contact with oceanic or continental carbon reservoirs) (38%) and iii) fromthe Amazon basin (21%). Based on these results we estimated the Delta C-14 endmember values for the different carbon reservoirs affecting our recordwhich suggest that the Amazon basin biospheric C-14 isoflux could have been reversed fromnegative to positive as early as the beginning of the 1970's. Thiswould imply amuch faster carbon turnover rate in the Amazon than previouslymodelled. (c) 2021 Elsevier B.V. All rights reserved.
- ItemThe Dry Puna as an ecological megapatch and the peopling of South America: Technology, mobility, and the development of a late Pleistocene/early Holocene Andean hunter-gatherer tradition in northern Chile(2017) Osorio, Daniela; Steele, James; Sepúlveda, Marcela; Gayo Hernández, Eugenia Monserrat; Capriles, José M.; Herrera, Katherine; Ugalde, Paula; De Pol-Holz, Ricardo; Latorre H., Claudio; Santoro, Calogero M.
- ItemThe pre-Columbian introduction and dispersal of Algarrobo (Prosopis, Section Algarobia) in the Atacama Desert of northern Chile(2017) Mc Rostie Bustamante, Virginia Bernardita; Gayo Hernández, Eugenia Monserrat; Santoro, Calogero M.; De Pol-Holz, Ricardo; Latorre H., Claudio
- ItemUsing archaeological shell middens as a proxy for past local coastal upwelling in northern Chile(2017) Latorre H., Claudio; De Pol-Holz, Ricardo; Carter, Chris; Santoroe, Calogero M.