114 results on '"MASSAFERRO, Julieta"'
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2. A multiproxy approach to reconstruct the Late Holocene environmental dynamics of the semiarid Andes of central Chile (29°S)
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Martel-Cea, Alejandra, primary, Maldonado, Antonio, additional, de Porras, María Eugenia, additional, Muñoz, Praxedes, additional, Maidana, Nora I., additional, Massaferro, Julieta, additional, and Schittek, Karsten, additional
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- 2023
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3. Impact of human activities and climate on Lake Morenito, Northern Patagonia, Argentina
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Mauad, Melina, Mayr, Christoph, Graßl, Teresa, Dubois, Nathalie, Serra, Maria Noel, and Massaferro, Julieta
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- 2020
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4. Multiproxy response to climate- and human-driven changes in a remote lake of southern Patagonia (Laguna Las Vizcachas, Argentina) during the last 1.6 kyr
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Quintana, Flavia A., Maidana, Nora I., Motta, Luciana, and Massaferro, Julieta
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- 2018
5. Climate and site-specific factors shape chironomid taxonomic and functional diversity patterns in northern Patagonia
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Motta, Luciana and Massaferro, Julieta
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- 2019
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6. A global database of Holocene paleotemperature records
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Kaufman, Darrell, McKay, Nicholas, Routson, Cody, Erb, Michael, Davis, Basil, Heiri, Oliver, Jaccard, Samuel, Tierney, Jessica, Dätwyler, Christoph, Axford, Yarrow, Brussel, Thomas, Cartapanis, Olivier, Chase, Brian, Dawson, Andria, de Vernal, Anne, Engels, Stefan, Jonkers, Lukas, Marsicek, Jeremiah, Moffa-Sánchez, Paola, Morrill, Carrie, Orsi, Anais, Rehfeld, Kira, Saunders, Krystyna, Sommer, Philipp S., Thomas, Elizabeth, Tonello, Marcela, Tóth, Mónika, Vachula, Richard, Andreev, Andrei, Bertrand, Sebastien, Biskaborn, Boris, Bringué, Manuel, Brooks, Stephen, Caniupán, Magaly, Chevalier, Manuel, Cwynar, Les, Emile-Geay, Julien, Fegyveresi, John, Feurdean, Angelica, Finsinger, Walter, Fortin, Marie-Claude, Foster, Louise, Fox, Mathew, Gajewski, Konrad, Grosjean, Martin, Hausmann, Sonja, Heinrichs, Markus, Holmes, Naomi, Ilyashuk, Boris, Ilyashuk, Elena, Juggins, Steve, Khider, Deborah, Koinig, Karin, Langdon, Peter, Larocque-Tobler, Isabelle, Li, Jianyong, Lotter, André, Luoto, Tomi, Mackay, Anson, Magyari, Eniko, Malevich, Steven, Mark, Bryan, Massaferro, Julieta, Montade, Vincent, Nazarova, Larisa, Novenko, Elena, Pařil, Petr, Pearson, Emma, Peros, Matthew, Pienitz, Reinhard, Płóciennik, Mateusz, Porinchu, David, Potito, Aaron, Rees, Andrew, Reinemann, Scott, Roberts, Stephen, Rolland, Nicolas, Salonen, Sakari, Self, Angela, Seppä, Heikki, Shala, Shyhrete, St-Jacques, Jeannine-Marie, Stenni, Barbara, Syrykh, Liudmila, Tarrats, Pol, Taylor, Karen, van den Bos, Valerie, Velle, Gaute, Wahl, Eugene, Walker, Ian, Wilmshurst, Janet, Zhang, Enlou, and Zhilich, Snezhana
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- 2020
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7. Publisher Correction: A global database of Holocene paleotemperature records
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Kaufman, Darrell, McKay, Nicholas, Routson, Cody, Erb, Michael, Davis, Basil, Heiri, Oliver, Jaccard, Samuel, Tierney, Jessica, Dätwyler, Christoph, Axford, Yarrow, Brussel, Thomas, Cartapanis, Olivier, Chase, Brian, Dawson, Andria, de Vernal, Anne, Engels, Stefan, Jonkers, Lukas, Marsicek, Jeremiah, Moffa-Sánchez, Paola, Morrill, Carrie, Orsi, Anais, Rehfeld, Kira, Saunders, Krystyna, Sommer, Philipp S., Thomas, Elizabeth, Tonello, Marcela, Tóth, Mónika, Vachula, Richard, Andreev, Andrei, Bertrand, Sebastien, Biskaborn, Boris, Bringué, Manuel, Brooks, Stephen, Caniupán, Magaly, Chevalier, Manuel, Cwynar, Les, Emile-Geay, Julien, Fegyveresi, John, Feurdean, Angelica, Finsinger, Walter, Fortin, Marie-Claude, Foster, Louise, Fox, Mathew, Gajewski, Konrad, Grosjean, Martin, Hausmann, Sonja, Heinrichs, Markus, Holmes, Naomi, Ilyashuk, Boris, Ilyashuk, Elena, Juggins, Steve, Khider, Deborah, Koinig, Karin, Langdon, Peter, Larocque-Tobler, Isabelle, Li, Jianyong, Lotter, André, Luoto, Tomi, Mackay, Anson, Magyari, Eniko, Malevich, Steven, Mark, Bryan, Massaferro, Julieta, Montade, Vincent, Nazarova, Larisa, Novenko, Elena, Pařil, Petr, Pearson, Emma, Peros, Matthew, Pienitz, Reinhard, Płóciennik, Mateusz, Porinchu, David, Potito, Aaron, Rees, Andrew, Reinemann, Scott, Roberts, Stephen, Rolland, Nicolas, Salonen, Sakari, Self, Angela, Seppä, Heikki, Shala, Shyhrete, St-Jacques, Jeannine-Marie, Stenni, Barbara, Syrykh, Liudmila, Tarrats, Pol, Taylor, Karen, van den Bos, Valerie, Velle, Gaute, Wahl, Eugene, Walker, Ian, Wilmshurst, Janet, Zhang, Enlou, and Zhilich, Snezhana
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- 2020
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8. Author Correction: A global database of Holocene paleotemperature records
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Kaufman, Darrell, McKay, Nicholas, Routson, Cody, Erb, Michael, Davis, Basil, Heiri, Oliver, Jaccard, Samuel, Tierney, Jessica, Dätwyler, Christoph, Axford, Yarrow, Brussel, Thomas, Cartapanis, Olivier, Chase, Brian, Dawson, Andria, de Vernal, Anne, Engels, Stefan, Jonkers, Lukas, Marsicek, Jeremiah, Moffa-Sánchez, Paola, Morrill, Carrie, Orsi, Anais, Rehfeld, Kira, Saunders, Krystyna, Sommer, Philipp S., Thomas, Elizabeth, Tonello, Marcela, Tóth, Mónika, Vachula, Richard, Andreev, Andrei, Bertrand, Sebastien, Biskaborn, Boris, Bringué, Manuel, Brooks, Stephen, Caniupán, Magaly, Chevalier, Manuel, Cwynar, Les, Emile-Geay, Julien, Fegyveresi, John, Feurdean, Angelica, Finsinger, Walter, Fortin, Marie-Claude, Foster, Louise, Fox, Mathew, Gajewski, Konrad, Grosjean, Martin, Hausmann, Sonja, Heinrichs, Markus, Holmes, Naomi, Ilyashuk, Boris, Ilyashuk, Elena, Juggins, Steve, Khider, Deborah, Koinig, Karin, Langdon, Peter, Larocque-Tobler, Isabelle, Li, Jianyong, Lotter, André, Luoto, Tomi, Mackay, Anson, Magyari, Eniko, Malevich, Steven, Mark, Bryan, Massaferro, Julieta, Montade, Vincent, Nazarova, Larisa, Novenko, Elena, Pařil, Petr, Pearson, Emma, Peros, Matthew, Pienitz, Reinhard, Płóciennik, Mateusz, Porinchu, David, Potito, Aaron, Rees, Andrew, Reinemann, Scott, Roberts, Stephen, Rolland, Nicolas, Salonen, Sakari, Self, Angela, Seppä, Heikki, Shala, Shyhrete, St-Jacques, Jeannine-Marie, Stenni, Barbara, Syrykh, Liudmila, Tarrats, Pol, Taylor, Karen, van den Bos, Valerie, Velle, Gaute, Wahl, Eugene, Walker, Ian, Wilmshurst, Janet, Zhang, Enlou, and Zhilich, Snezhana
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- 2020
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9. A 2200-year record of Andean Condor diet and nest site usage reflects natural and anthropogenic stressors
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Duda, Matthew P., primary, Grooms, Christopher, additional, Sympson, Lorenzo, additional, Blais, Jules M., additional, Dagodzo, Daniel, additional, Feng, Wenxi, additional, Hayward, Kristen M., additional, Julius, Matthew L., additional, Kimpe, Linda E., additional, Lambertucci, Sergio A., additional, Layton-Matthews, Daniel, additional, Lougheed, Stephen C., additional, Massaferro, Julieta, additional, Michelutti, Neal, additional, Pufahl, Peir K., additional, Vuletich, April, additional, and Smol, John P., additional
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- 2023
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10. Contrasting responses of lake ecosystems to environmental disturbance: a paleoecological perspective from northern Patagonia (Argentina)
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Massaferro, Julieta, Correa-Metrio, Alex, Montes de Oca, Fernanda, and Mauad, Melina
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- 2018
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11. Duda et al. 2022_supplementary material.docx from An approximately 2200-year record of andean condor diet and nest site usage reflects natural and anthropogenic stressors
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Duda, Matthew P., Grooms, Christopher, Sympson, Lorenzo, Blais, Jules M., Dagodzo, Daniel, Feng, Wenxi, Hayward, Kristen M., Julius, Matthew L., Kimpe, Linda E., Lambertucci, Sergio A., Layton-Matthews, Daniel, Lougheed, Stephen C., Massaferro, Julieta, Michelutti, Neal, Pufahl, Peir K., Vuletich, April, and Smol, John P.
- Abstract
Understanding how animals respond to large-scale environmental changes is difficult to assess because monitoring data are rarely available for more than the last few decades, if at all. Here, we demonstrate how a variety of paleoecological proxies (e.g. isotopes, geochemistry and DNA) from an Andean Condor (Vultur gryphus) guano deposit from Argentina can be used to explore breeding site fidelity and the impacts of environmental changes on avian behaviour. We found that condors used the nesting site since at least approximately 2200 years ago, with an approximately 1000-year nesting frequency slowdown from ca. 1650 to 650 BP. We provide evidence that the nesting slowdown may have been caused by a period of increased volcanic activity in the nearby Southern Volcanic Zone, which resulted in decreased availability of carrion and deterred scavenging birds. After returning to the nest site ca. 650 BP, condor diet shifted from the carrion of native species and beached marine animals to the carrion of livestock (e.g. sheep and cattle) and exotic herbivores (e.g. red deer and European hare) introduced by European settlers. Currently, Andean Condors have elevated lead concentrations in their guano compared to the past, which is associated with human persecution linked to the shift in diet.
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- 2023
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12. Sub-fossil chironomids as indicators of hydrological changes in the shallow and high-altitude lake Shen Co, Tibetan Plateau, over the past two centuries
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Rigterink, Sonja, primary, Echeverría-Galindo, Paula, additional, Martínez-Abarca, Rodrigo, additional, Massaferro, Julieta, additional, Hoelzmann, Philipp, additional, Wünnemann, Bernd, additional, Laug, Andreas, additional, Pérez, Liseth, additional, Kang, Wengang, additional, Börner, Nicole, additional, Schwarz, Anja, additional, Peng, Ping, additional, Wang, Junbo, additional, Zhu, Liping, additional, and Schwalb, Antje, additional
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- 2022
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13. Searching for the Little Ice Age in the last ~900 yrs record of the shallow lake Laguna Polo, Patagonia, Argentina
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Charqueño-Celis, Fernanda, Mayr, Christoph, Perez, Liseth, Dubois, Nathalie, Massaferro, Julieta, Hassan, Gabriela S., de Porras, M. Eugenia, Halac, Silvana R., and Córdoba, Francisco E.
- Abstract
The records of the Little Ice Age (LIA) in lacustrine sediments from southern south America (SSA) are still rare. Indeed, most of the evidence of this period in SSA comes from tree rings records. Our main goal was identifying the signal of the LIA at Laguna Polo (49° 15’ 59.4” S, 72° 53’ 38.4” W), in Santa Cruz, southern part of Patagonia. For this multiproxy reconstruction, we analyzed a 54-cm long sediment core and conducted paleoecological analysis on testate amoebae and chironomids in combination with grain-size distribution and geochemical composition (TOC, TIC, TN, biogenic silica (BiSi), δ15N, δ13C and C/N). The age model, based on radiocarbon dates and tephrochronology, indicated a basal age of ca. AD 1300. Based on the biological proxies, we divided our record into 4 zones. In zone 3 an important ecological change in both bioproxies was detected for the period AD 1420 to 1780. On the one hand, testate amoebae show an increase in abundance but a decrease in diversity. Difflugids were highly abundant and were dominated by Difflugia glans. Chironomid assemblages, on the other hand, reveal a decrease in abundance of head capsules but an increase in diversity with the appearance of Cricotopus and Dicrotendipes. The taxa of both taxonomic groups found during this period have been reported as indicators of cold environments. Grain-size analyses indicate a concurrent proportional increase in silts and clays, whereas geochemical analyses record a decrease in TN, TOC, TIC, BiSi, δ13C and the C/N ratio, but an increase of δ15N which may be indicative of a cooler and wetter period, as has been previously described during the LIA period in Patagonia., IAL-IPA 2022 Abstract Book - Lagos Memorias del Territorio
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- 2022
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14. Living organisms and sedimentary remains from high mountain lakes in the Alps
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Marchetto, Aldo, primary, Boggero, Angela, additional, Fontaneto, Diego, additional, Lami, Andrea, additional, Lotter, André F., additional, Manca, Marina M., additional, Massaferro, Julieta, additional, Mosello, Rosario, additional, Musazzi, Simona, additional, Nickus, Ulrike, additional, Psenner, Roland, additional, Rogora, Michela, additional, Sorvari Stundet, Sanna, additional, Stuchlik, Evzen, additional, Tartari, Gabriele A,, additional, Thies, Hansjörg, additional, and Tolotti, Monica, additional
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- 2021
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15. Bioindicators of climate and trophic state in lowland and highland aquatic ecosystems of the Northern Neotropics
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Pérez, Liseth, Lorenschat, Julia, Massaferro, Julieta, Pailles, Christine, Sylvestre, Florence, Hollwedel, Werner, Brandorff, Gerd-Oltmann, Brenner, Mark, Islebe, Gerald, del Socorro Lozano, MarÃa, Scharf, Burkhard, and Schwalb, Antje
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- 2013
16. Long Term Turnover of a Fossil Community of Chironomids (Diptera) from Lake Mascardi (Patagonia, Argentina)
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Corley, Juan C. and Massaferro, Julieta I.
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- 1998
17. Patagonian ostracods as indicators of climate-related hydrological variables: implications for paleoenvironmental reconstructions in Southern South America
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Mercau, Josefina Ramón, Laprida, Cecilia, Massaferro, Julieta, Rogora, Michela, Tartari, Gabriele, and Maidana, Nora I.
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- 2012
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18. Palaeolimnology of Lake Hess (Patagonia, Argentina): multi-proxy analyses of short sediment cores
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Guilizzoni, Piero, Massaferro, Julieta, Lami, Andrea, Piovano, Eduardo Luis, Guevara, Sergio Ribeiro, Formica, Stella Maris, Daga, Romina, Rizzo, Andrea, and Gerli, Stefano
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- 2009
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19. Testate amoebae (Amoebozoa: Arcellinidae) as indicators of dissolved oxygen concentration and water depth in lakes of the Lacandón Forest, southern Mexico
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Charqueño Celis, Norma Fernanda, Garibay, Martin, Sigala, Itzel, Brenner, Mark, Echeverria Galindo, Paula, Lozano García, Socorro, Massaferro, Julieta, and Pérez, Liseth
- Subjects
LACANDÓN FOREST ,NEOTROPICS ,Testate amoebae -- neotropics -- bioindicators -- dissolved oxygen -- water depth -- Lacandón Forest ,Article ,BIOINDICATORS ,purl.org/becyt/ford/1 [https] ,purl.org/becyt/ford/1.5 [https] ,neotropics ,water depth ,Veröffentlichung der TU Braunschweig ,lcsh:Physical geography ,lcsh:Environmental sciences ,ddc:5 ,Lacandón Forest ,lcsh:GE1-350 ,WATER DEPTH ,lcsh:Geography. Anthropology. Recreation ,TESTATE AMOEBAE ,DISSOLVED OXYGEN ,lcsh:G ,dissolved oxygen ,bioindicators ,ddc:55 ,Publikationsfonds der TU Braunschweig ,Testate amoebae ,lcsh:GB3-5030 - Abstract
The ecology of aquatic protists such as testate amoebae is poorly known worldwide, but is almost completely unknown in lakes of the northern Neotropics. To address this knowledge gap, we analyzed testate amoebae (Amoebozoa: Arcellinidae) in lakes of the Lacandón Forest, one of the most biodiverse parts of southern México. We set out to evaluate the diversity of testate amoebae communities and assess whether testate amoebae taxa are reliable indicators of environmental variables dissolved oxygen and water depth. We collected 17 surface sediment samples from a range of water depths in six lakes across the Naha-Metzabok Biosphere Reserve, northeastern Chiapas state. We identified 15 testate amoebae taxa distributed across seven genera. Eleven were identified to species level and four to strain (infra-subspecific level), and taxa were distributed unevenly among samples. Distribution of taxa in samples was related to dissolved oxygen (DO) concentration in the water measured near the sediment surface. Arcella discoides and Centropyxis aculeata strain “aculeata” were the most tolerant of low oxygen concentrations, whereas the other taxa require higher DO levels. The influence of oxygen was also seen at the assemblage level. Sites with low DO concentrations had Shannon Diversity Index (SDI) values
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- 2019
20. First record of the Pseudodiamesa branickii species group (Diptera: Chironomidae: Diamesinae) from central Mexico
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Moreno, Joanna, primary, Massaferro, Julieta, additional, Caballero, Margarita, additional, and Oseguera, Luis, additional
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- 2020
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21. Testate amoebae (Amoebozoa: Arcellinidae) as indicators of dissolved oxygen concentration and water depth in lakes of the Lacandón Forest, southern Mexico
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Charqueño Celis, Norma Fernanda, primary, Garibay, Martin, additional, Sigala, Itzel, additional, Brenner, Mark, additional, Echeverria-Galindo, Paula, additional, Lozano, Socorro, additional, Massaferro, Julieta, additional, and Pérez, Liseth, additional
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- 2019
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22. Impact of human activities and climate on Lake Morenito, Northern Patagonia, Argentina
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Mauad, Melina, primary, Mayr, Christoph, additional, Graßl, Teresa, additional, Dubois, Nathalie, additional, Serra, Maria Noel, additional, and Massaferro, Julieta, additional
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- 2019
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23. A multi-proxy Late-glacial palaeoenvironmental record from Lake Bled, Slovenia
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Andrič, Maja, Massaferro, Julieta, Eicher, Ueli, Ammann, Brigitta, Leuenberger, Markus Christian, Martinčič, Andrej, Marinova, Elena, and Brancelj, Anton
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- 2009
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24. A multi-centennial humid anomaly in the Altiplano: tropical and extra-tropical drivers of the South America Summer Monsoon during recent millennia
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Jara, Ignacio A., Maldonado, Antonio, de Porras, Maria Eugenia, Maidana, Nora, Massaferro, Julieta, Hernández, Armand, Uribe, Mauricio, Jara, Ignacio A., Maldonado, Antonio, de Porras, Maria Eugenia, Maidana, Nora, Massaferro, Julieta, Hernández, Armand, and Uribe, Mauricio
- Abstract
The South American Summer Monsoon (SASM) is the most important atmospheric system in tropical South America, being the major supplier of precipitation north of 20°S. Modern climatological studies indicate that year-to-year changes of the SASM are influenced by large-scale modes of atmospheric circulation sourced in the tropics such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). The interplay between these modes results in pronounced precipitation anomalies in the tropical Andes and the Altiplano which impact numerous socioeconomic activities. The drivers behind SASM variations at longer timescales are, however, far less understood due to the shortness of modern instrumental timeseries and the relative low number of paleorecords. This prevents an evaluation of past feedback mechanisms, and whether or not the historical ranges of variation represent the expected boundaries for future conditions. In this presentation we will show three new pollen-based climate reconstructions expanding the last 4000 years from the Chilean Altiplano (18-21°S), two lake sediment records and one series of 32 fossil rodent middens. The Chilean Altiplano is located at the southern margin of the SASM influence, where up to 90% of annual rainfall derives from the easterly penetration of the SASM during the austral summer. These precipitation patterns exert a tight control on the altitudinal distribution of the main vegetation communities. Hence, our pollen reconstructions allowed a fine characterization of past vegetation changes caused by shifts in the strength of the SASM during recent millennia. The chronology of the two lake cores is based on multiple AMS 14C dating, while all rodent deposits were individually dated, providing key complementary short-term information at punctual times. Our pollen records reveal significant changes in vegetation at multi-centennial timescales, most notably a marked expansion of high-Andean vegetation along with signif
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- 2019
25. The species richness-elevation relationship: global patterns of variation in chironomid richness in mountain lakes
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Motta, Luciana, Ruggiero, Adriana, de Mendoza, Guillermo, Massaferro, Julieta, Motta, Luciana, Ruggiero, Adriana, de Mendoza, Guillermo, and Massaferro, Julieta
- Abstract
1. The species richness-elevation relationship (SRE) is predominantly hump-shaped along terrestrial gradients, but has been less explored in aquatic environments. Chironomids were used to evaluate the generality of the SRE in mountain lakes, and the role of methodological and biological factors in determining its shape. 2. The shape of 39 chironomid SREs distributed worldwide was identified by consensus between statistical and visual methods. A ‘coefficient of methodological integrity’ (Cin) was developed to combine information on sampling effort and homogeneity, and elevational extent in order to quantify the adherence of each dataset to methodological standards known to influence the SRE. Differences in the shape of the SRE between biogeographical regions, biomes and climatic regions were tested using Fisher’s exact tests. A formal meta-analysis was conducted to quantify the overall strength of the SRE, and its association with geographical extent, sampling technique, biogeography, biomes and climate. 3. The SRE presented multiple forms, with considerable variation between identification methods. The most satisfactory datasets (i.e. lowest Cin values), showed predominance of non-linear (low-plateau and hump-shaped) patterns. The Cin explained ~21% of pattern variation. Neither biogeography, nor biomes or climatic regions accounted for differences in the shape of the SRE. 4. The global predominance of non-linear SRE suggests that chironomid richness generally remains high in lakes at mid-elevations, decreasing sharply towards high elevations. As previously known for terrestrial environments, identification of SRE shape is influenced by analytical method. Whenever possible, tailoring the sampling design to increase methodological integrity will reduce uncertainty in the identification of SRE shape in mountain lakes.
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- 2019
26. Diptera: Chironomidae
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Massaferro, Julieta, Araneda Castillo, Alberto Eduardo, Motta, Luciana Maria, Pérez, Liseth, Massaferro, Julieta, and Correa Metrio, Alexander
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purl.org/becyt/ford/1 [https] ,CUATERNARIO ,purl.org/becyt/ford/1.5 [https] ,CHIRONOMIDAE ,PALEOBIOINDICADORES ,NEOTROPICO ,LAGOS - Abstract
En este capítulo se presenta el uso de los quironómidos como paleoindicadores ambientales en la región Neotropical, discutiéndose aspectos relativos a las variables que se pueden reconstruir en base a este grupo de insectos, a los sectores geográficos que han sido cubiertos por estos estudios a las interrogantes respecto del pasado climático, que estos estudios pueden ayudar a responder y a los estudios futuros que pueden realizarse en esta temática en diferentes subzonas de la región Neotropical. Fil: Massaferro, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Administración de Parques Nacionales. Parque Nacional "Nahuel Huapi"; Argentina Fil: Araneda Castillo, Alberto Eduardo. Universidad de Concepción; Chile Fil: Motta, Luciana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Administración de Parques Nacionales. Parque Nacional "Nahuel Huapi"; Argentina
- Published
- 2017
27. First human impacts and responses of aquatic systems: a review of palaeolimnological records from around the world
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Dubois, Nathalie, Saulnier-Talbot, Émilie, Mills, Keely, Gell, Peter, Battarbee, Rick, Bennion, Helen, Chawchai, Sakonvan, Dong, Xuhui, Francus, Pierre, Flower, Roger, Gomes, Doriedson F, Gregory-Eaves, Irene, Humane, Sumedh, Kattel, Giri, Jenny, JeanPhilippe, Langdon, Peter, Massaferro, Julieta, McGowan, Suzanne, Mikomägi, Annika, Ngoc, Nguyen Thi Minh, Ratnayake, Amila Sandaruwan, Reid, Michael, Rose, Neil, Saros, Jasmine, Schillereff, Daniel, Tolotti, Monica, Valero-Garcés, Blas, Dubois, Nathalie, Saulnier-Talbot, Émilie, Mills, Keely, Gell, Peter, Battarbee, Rick, Bennion, Helen, Chawchai, Sakonvan, Dong, Xuhui, Francus, Pierre, Flower, Roger, Gomes, Doriedson F, Gregory-Eaves, Irene, Humane, Sumedh, Kattel, Giri, Jenny, JeanPhilippe, Langdon, Peter, Massaferro, Julieta, McGowan, Suzanne, Mikomägi, Annika, Ngoc, Nguyen Thi Minh, Ratnayake, Amila Sandaruwan, Reid, Michael, Rose, Neil, Saros, Jasmine, Schillereff, Daniel, Tolotti, Monica, and Valero-Garcés, Blas
- Abstract
Lake sediments constitute natural archives of past environmental changes. Historically, research has focused mainly on generating regional climate records, but records of human impacts caused by land use and exploitation of freshwater resources are now attracting scientific and management interests. Long-term environmental records are useful to establish ecosystem reference conditions, enabling comparisons with current environments and potentially allowing future trajectories to be more tightly constrained. Here we review the timing and onset of human disturbance in and around inland water ecosystems as revealed through sedimentary archives from around the world. Palaeolimnology provides access to a wealth of information reflecting early human activities and their corresponding aquatic ecological shifts. First human impacts on aquatic systems and their watersheds are highly variable in time and space. Landscape disturbance often constitutes the first anthropogenic signal in palaeolimnological records. While the effects of humans at the landscape level are relatively easily demonstrated, the earliest signals of human-induced changes in the structure and functioning of aquatic ecosystems need very careful investigation using multiple proxies. Additional studies will improve our understanding of linkages between human settlements, their exploitation of land and water resources, and the downstream effects on continental waters
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- 2018
28. First human impacts and responses of aquatic systems: A review of palaeolimnological records from around the world
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Dubois Nathalie, Saulnier-Talbot Emilie, Mills Keely, Gell Peter, Battarbee Rick, Bennion Helen, Chawchai Sakonvan, Dong Xuhui, Francus Pierre, Flower Roger, Gomes Doriedson F., Gregory-Eaves Irene, Humane Sumedh, Kattel Giri, Jenny JeanPhilippe, Langdon Peter, Massaferro Julieta, McGowan Suzanne, Mikomagi Annika, Nguyen Thi Minh Ngoc, Ratnayake Amila Sandaruwan, Reid Michael, Rose Neil, Saros Jasmine, Schillereff Daniel, Tolotti Monica, Valero-Garces Blas, Dubois Nathalie, Saulnier-Talbot Emilie, Mills Keely, Gell Peter, Battarbee Rick, Bennion Helen, Chawchai Sakonvan, Dong Xuhui, Francus Pierre, Flower Roger, Gomes Doriedson F., Gregory-Eaves Irene, Humane Sumedh, Kattel Giri, Jenny JeanPhilippe, Langdon Peter, Massaferro Julieta, McGowan Suzanne, Mikomagi Annika, Nguyen Thi Minh Ngoc, Ratnayake Amila Sandaruwan, Reid Michael, Rose Neil, Saros Jasmine, Schillereff Daniel, Tolotti Monica, and Valero-Garces Blas
- Published
- 2018
29. Deciphering long-term records of natural variability and human impact as recorded in lake sediments: a palaeolimnological puzzle
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Mills, Keely, Schillereff, Daniel, Gell, Peter, Anderson, N. John, Arnaud, Fabien, Dong, Xuhui, Jones, Matthew, McGowan, Suzanne, Massaferro, Julieta, Moorhouse, Heather, Perez, Liseth, and Ryves, David B.
- Abstract
Global aquatic ecosystems are under increasing threat from anthropogenic activity, as well as being exposed to past (and projected) climate change, however, the nature of how climate and human impacts are recorded in lake sediments is often ambiguous. Natural and anthropogenic drivers can force a similar response in lake systems, yet the ability to attribute what change recorded in lake sediments is natural, from that which is anthropogenic, is increasingly important for understanding how lake systems have, and will continue to function when subjected to multiple stressors; an issue that is particularly acute when considering management options for aquatic ecosystems. The duration and timing of human impacts on lake systems varies geographically, with some regions of the world (such as Africa and South America) having a longer legacy of human impact than others(e.g. New Zealand). A wide array of techniques (biological, chemical, physical and statistical) is available to palaeolimnologists to allow the deciphering of complex sedimentary records. Lake sediments are an important archive of how drivers have changed through time, and how these impacts manifest in lake systems. With a paucity of ‘real‐time’ data pre‐dating human impact, palaeolimnological archives offer the only insight into both natural variability (i.e. that driven by climate and intrinsic lake processes) and the impact of people. Whilst there is a need to acknowledge complexity, and temporal and spatial variability when deciphering change from sediment archives, a palaeolimnological approach is a powerful tool for better understanding and managing global aquatic resources.
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- 2017
30. Testate amoebae (Amoebozoa: Arcellinidae) as indicators of dissolved oxygen concentration and water depth in lakes of the Lacandón Forest, southern Mexico.
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Fernanda Charqueño-Celis, Norma, Garibay, Martin, Sigala, Itzel, Brenner, Mark, Echeverria-Galindo, Paula, Lozano-García, Socorro, Massaferro, Julieta, and Pérez, Liseth
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DISSOLVED oxygen in water ,WATER depth ,OXYGEN detectors ,AMOEBA ,LAKES ,ENVIRONMENTAL indicators - Abstract
The ecology of aquatic protists such as testate amoebae is poorly known worldwide, but is almost completely unknown in lakes of the northern Neotropics. To address this knowledge gap, we analyzed testate amoebae (Amoebozoa: Arcellinidae) in lakes of the Lacandón Forest, one of the most biodiverse parts of southern México. We set out to evaluate the diversity of testate amoebae communities and assess whether testate amoebae taxa are reliable indicators of environmental variables dissolved oxygen and water depth. We collected 17 surface sediment samples from a range of water depths in six lakes across the Naha-Metzabok Biosphere Reserve, northeastern Chiapas state. We identified 15 testate amoebae taxa distributed across seven genera. Eleven were identified to species level and four to strain (infra-subspecific level), and taxa were distributed unevenly among samples. Distribution of taxa in samples was related to dissolved oxygen (DO) concentration in the water measured near the sediment surface. Arcella discoides and Centropyxis aculeata strain "aculeata" were the most tolerant of low oxygen concentrations, whereas the other taxa require higher DO levels. The influence of oxygen was also seen at the assemblage level. Sites with low DO concentrations had Shannon Diversity Index (SDI) values <1.5, an indication of stressful ambient conditions. We identified two species assemblage types, which are distinguished by their oxygen concentration requirements. Assemblage 1 was more diverse and possessed species that are intolerant of low oxygen concentrations, whereas Assemblage 2 possessed fewer, rarer, opportunistic species that tolerate stressful conditions. Low oxygen concentrations are related to water depth and the combination of these two variables is important in determining the composition of testate amoebae assemblages in Lacandón Forest lakes. Quantitative relationships between testate amoebae assemblages and water depth will enable use of sedimented amoebae remains for paleolimnological inference of past water level changes in lakes of the Lacandón Forest. [ABSTRACT FROM AUTHOR]
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- 2020
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31. Contrasting responses of lake ecosystems to environmental disturbance: a paleoecological perspective from northern Patagonia (Argentina)
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Massaferro, Julieta, primary, Correa-Metrio, Alex, additional, Montes de Oca, Fernanda, additional, and Mauad, Melina, additional
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- 2017
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32. Paleobioindicadores del fin del mundo: ostrácodos y quironómidos del extremo sur de Sudamérica en ambientes lacustres cuaternarios
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Laprida, Cecilia, Massaferro, Julieta, Ramón Mercau, María Josefina, and Cusminsky, Gabriela Catalina
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purl.org/becyt/ford/1 [https] ,purl.org/becyt/ford/1.5 [https] ,Ambientes lacustres cuaternarios ,Argentina ,Ostrácodos ,Paleontología ,CIENCIAS NATURALES Y EXACTAS ,Ciencias de la Tierra y relacionadas con el Medio Ambiente ,Quironómidos - Abstract
El objetivo de este trabajo es resumir el estado de las investigaciones paleolimnológicas basadas en bioindicadores pertenecientes al Phylum Arthropoda, en particular ostrácodos (Crustacea) y quironómidos (Diptera), en el ámbito de la República Argentina. Si bien la mayor parte de las investigaciones se han efectuado en el ámbito de la Patagonia, donde han permitido la reconstrucción paleolimnológica de registros desde el último Máximo Glacial y el Holoceno, estos estudios se fueron extendiendo progresivamente hacia las regiones pampeanas, Cuyo y el Noroeste, abarcando distintas ventanas temporales del Pleistoceno Superior y el Holoceno. Son cada vez más numerosas las investigaciones que integran datos actuales y fósiles de ostrácodos y quironómidos, lo que ha permitido, desarrollar funciones de transferencia dando lugar a reconstrucciones cuantitativas robustas y mejorar las interpretaciones cualitativas basadas en la presencia de especies indicadoras. Ambos tipos de reconstrucciones son cada vez más frecuentemente combinadas con otros proxies biológicos, químicos o físicos, brindando un marco multiproxy que permite reconstrucciones integrales de los ecosistemas lacustres cuaternarios. Los estudios de ostrácodos y quironómidos de registros lacustres han permitido no sólo reconocer las tendencias ambientales y climáticas de los últimos miles de años, sino también reconocer eventos climáticos de media y alta frecuencia de interés global, tales como el Younger Dryas, el Antarctic Cold Reversal, el Evento frio 4.2k, la Pequeña Edad de Hielo, y también los cambios climáticos e impactos antrópicos del siglo 20. Fil: Laprida, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Massaferro, Julieta. Administración de Parques Nacionales. Parque Nacional "nahuel Huapi"; Argentina Fil: Ramón Mercau, María Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Cusminsky, Gabriela Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina
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- 2015
33. Alotanypus vittigera Edwards 1931, comb. nov
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Siri, Augusto, Donato, Mariano, Orpella, Germán, and Massaferro, Julieta
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Insecta ,Arthropoda ,Diptera ,Animalia ,Alotanypus ,Biodiversity ,Chironomidae ,Alotanypus vittigera ,Taxonomy - Abstract
Alotanypus vittigera (Edwards, 1931), comb. nov. Anatopynia vittigera Edwards 1931: 242 ���243, fig. 36 b; Spies & Reiss 1996: 82 (listed as unplaced valid species). Type material (all in NHM). HOLOTYPE male (NHM) L. Nahuel Huapi, Eastern end, R��o Negro province, Argentina, 28���31.x. 1926, F.W. Edwards. Paratypes. 3 males and 2 females same date as holotype; 1 male and 2 females, L. Correntoso, R��o Negro province, Argentina, 18���25.xi. 1926, F.W. Edwards; 1 male, Bariloche, R��o Negro province, Argentina, 25���28.xi. 1926, F.W. Edwards; 1 male, Puerto Montt, Llanquihue province, S. Chile, 24.xii. 1926, F.W. Edwards. Recently collected material. 1 male and 2 females from 41 ��00��56 ����S, 71 �� 49��54 ����W, 856 m, Mall��n La Heladera, Puerto Blest, PNNH, R��o Negro province, Argentina, 07.i���04.ii. 2007, Garr�� & Montes de Oca, Malaise trap, and 3 fourth instar larvae from same site, 04.ii. 2007, Garr�� & Montes de Oca, Kick sample; 4 males with their pupal exuviae and 2 females with their pupal exuviae (all adults emerged same day of collection) from 41 �� 36��06����S, 71 �� 36��25 ����W, temporary pool beside Vertiente stream, Manso Inferior, PNNH, R��o Negro province, Argentina, 10.i. 2008, G. Orpella; 1 male with its pupal exuviae (adult emerged on 12.ii. 2009), 2 females with their pupal exuviae (both adults emerged on 11.ii. 2009), 1 prepupa and 2 fourth instar larvae, 41 ��00��05����S, 71 �� 50��53 ����W, 855 m, Mall��n La Heladera, Puerto Blest, PNNH, R��o Negro province, Argentina, 11.ii. 2009, A. Siri, kick sample. Emended diagnosis. The diagnosis of Alotanypus vittigera (Edwards) comb. nov. should be emended as follows: Male: vittae strongly or not indicated; AR lesser or slightly higher than 2.0; anepisternals, preepisternals and postnotals present or absent; LR I = 0.60���0.75. Pupa: Thoracic seta DC 1 shorter or longer than DC 3. Descriptions. Male (n = 5���12, except when otherwise stated) (Figs. 1���8) Total length 5.15���6.23 mm. Total length / wing length 1.61���1.89. Coloration: Thorax yellowish brown to dark brown, with or without evident vittae. Anepisternum, preepisternum and postnotum dark brown; abdomen as Fig. 1. Wing with several dark spots on membrane; macrotrichia above dark spots thick and densely grouped; central section of Cu, cross-veins RM and MCu, FCu and basal section of M 3 + 4 darkened (Fig. 2). Head: Antenna; AR 1.9���2.1 [1.95]. Temporals multiserial 42���76 [71]; postorbitals bi to multiserial, 21���26 [21]. Clypeus with 7���20 [11] setae. Tentorium 257���274 [270] long (4). Palpomere lengths (1���5) 59���84 [70]; 101��� 148 [145]; 153���195 [150]; 227���282 [250]; 315���415. Thorax. Antepronotum with 12���19 [17] lateral setae; humerals 14 (1); acrostichals biserials between vittae, diverging as uni to multiserial, merging with the dorsocentrals in the prescutelar area; dorsocentrals 44 (1); prealars 26���38 [35]; supraalar 1; anepisternals 0���3 [3]; scutellars 35���86 [76]; postnotum with 0���10 [0]; preepisternals absent. Wing with macrotrichia in all cells except to r 1 and r 2 + 3; length 3.10���3.80 [3.30] mm; width 0.90���1.06 [0.93] mm. L / W = 3.26���4.12 [3.55]. VR 0.88���0.97 [0.94]. C extended beyond R 4 + 5. Brachiolum with 4���8 distal setae, plus 4���5 proximal setae. Squama fringed with up to 65 setae. Legs. Tibial spur on p 1 with slightly curved apex, 102���116 [113] long; comb on p 1 with 9���13 [10] short spines (Fig. 3). Tibial spurs on p 2 95���120 [115] and 63���83 [75] long (Fig. 4). Tibial spurs on p 3 91���120 [113] and 69���81 [75] long (Fig. 5); spur ratio 0.65���0.74 [0.66]; comb on p 3 with 10���12 [12] spines, the outer slightly "S" curved (Fig. 6). Two pseudospurs on ta 1���2 of p 2 and ta 1 of p 3. Lengths and proportions of legs in Table 3. fe ti ta 1 ta 2 ta 3 p 1 1307���1563 [1540] 1652���1880 [1750] 1224���1351 [1200] 625���717 [625] 415���497 [463] p 2 1452���1629 [1588] 1593���1805 [1750] 1017���1152 [1063] 525���612 [525] 350���418 [350] p 3 1245���1468 [1325] 1780���2095 [2000] 1328���1544 [1413] 665���795 [725] 428���530 [475] continued. ta 4 ta 5 LR BV SV p 1 259���327 [275] 172���226 [200] 0.68���0.76 [0.69] 2.65���2.93 [2.87] 2.38���2.74 [2.74] p 2 208���249 [225] 165���200 [200] 0.60���0.66 [0.61] 3.13���3.39 [3.39] 2.91���3.17 [3.14] p 3 268���324 [288] 180���207 [200] 0.68���0.76 [0.71] 2.59���2.96 [2.81] 2.27���2.52 [2.35] Hypopygium (Fig. 7). Setae on tergite IX, 17���24. Gonocoxite 249���291 [280] long. Gonostylus 135���161 [145] long. Aberrant specimens (3) with a very thick megaseta-like lateral to the megaseta; 1 aberrant specimen with the very thick megaseta-like, plus 1 additional strong spine (Fig. 8). HR 1.65���2.04 [1.93]; HV 1.97���2.41. Female (n = 5���7, except when otherwise stated) (Figs. 9���11) Total length 4.50���5.15 (4). Total length / wing length 1.27���1.44 (4). Coloration: Thorax and wing spots as in male; cercus yelowish. Head. Antenna with 14 flagellomeres, AR 0.21���0.23 (4). Temporal setae multiserial, 74 (1), postorbitals bi to multiserial, 45 (1). Clypeus with 16���21 setae. Palpomere lengths (I���V) 70���90; 102���150; 150���200; 220���303; 210 (1) long. Thorax. Antepronotum with 15���26 lateral setae and 0���4 dorsal setae. Acrostichals as in male; prealars 33���55; supraalar 1; anepisternals 1���6 (4), scutelars 86���118. Preepisternals and postnotals absent. Wing with macrotrichia in all cells except to r 1 and r 2 + 3; length 3.40���3.70 mm; width 1.16���1.50 mm; L / W = 2.39���2.90. VR 0.92���0.97. C extended beyond R 4 + 5. Squama fringed with 60���87 setae. Macrotrichia above dark spots thick and densely grouped Legs. Tibial spur on p 1 95���120 long; on p 2 93���128 and 66���88 long; on p 3 93���120 and 73���83 long. Spur ratio on p 3 0.65���0.78. Comb on p 3 with 9���12 spines; no tibial comb on p 1. Two pseudospurs on ta 1���3 of p 2 and ta 1 of p 3. Lengths and proportions of legs in Table 4. Genitalia (Fig. 9). Cercus 81���125 long. Seminal capsule 91���125 long (Fig. 10); notum 216���300 long (2); tergite IX with 0���5 setae (3) (Fig. 11); segment X with 6���13 setae (4). Pupa (n = 4���9, except when otherwise stated) (Figs. 12���17) Total length 6.25���8.30 mm. Cephalothorax (Fig. 12). Frontal apotome as in Fig. 13. Thoracic horn (Fig. 14) arising from a distinct tubercle; external membrane with spines; respiratory atrium almost straight. Length 524���596; width 106���135; L / W 4.41��� 4.95; plastron plate 58���85 long; 97���132 wide; plastron plate length / thoracic horn length 0.11���0.15. Thoracic setation (Fig. 15): DC 1 41���54; DC 3 95���140; Sa 203 long (1); MAps 175���188 long (2). Abdomen. Scar on segment I, 216���249 long. Shagreen with single spines. Chaetotaxy (Figs. 16, 17): D 1 more or less straight, arising from a distinct tubercle on segments I���VII. D 1 is situated in the same line or slightly posteriorly to D 2 in segments VI and VII. D 2 and D 4 longer than D 1, arising from a distinct tubercle in segments II���VII. D 3 and D 5 short and thin, arising from a very short tubercle or tubercle absent. Segments I���VI with two pairs of FIGURES 12���26. Alotanypus vittigera (Edwards) comb. nov. immatures. Pupa: 12, cephalothorax; 13, frontal apotome; 14, thoracic horn; 15, thoracic setae: Dc 1, Dc 2 and Sa from left to right; 16, complete abdominal setation; 17, tergite and sternite of abdominal IV segment. Fourth-instar larva: 18, ventral cephalic setation; 19, dorsal cephalic setation; 20, antennite I; 21, apex of antenna; 22, mandible; 23, ligula; 24, dorsomental teeth; 25, procercus; 26, simple claws of posterior parapod. Scale bars = 20 ��m for Fig. 21; 50 ��m for Figs. 13, 24, 26; 100 ��m for Figs. 12, 15, 20, 22, 23, 25; 200 ��m for Figs. 14, 17; 500 ��m for Fig. 16. short lateral setae. Segments VII and VIII with 5; anal lobe with 2 pairs of long and teniated lateral setae. Position of LS 1 / segment length = 0.45���0.51 on segment VII; 0.22���0.27 on segment VIII. Anal lobe 803���996 long; 400��� 450 wide; L / W 1.93���2.05. Position of LS / anal lobe length 0.16���0.18 for LS 1 and 0.27���0.28 for LS 2. Male genital sac 355���387 long; length of male genital sac / length of anal lobe 0.42���0.44. Fourth-instar larva (n = 5���6, except when otherwise stated) (Figs. 18���26) Total length 0.77���0.91 mm (2). Head: capsule 620���800; 820���1000 wide. CI 0.76���0.85. Cephalic setation: Ventral (Fig. 18): SSm between S 9 and S 10;SSm close to S 10 and VP posterior to S 10. Dorsal (Fig. 19): S 7, S 8 and DP arranged in a line; S 6 anterolateraly to S 7. Antenna (Figs. 20, 21). AR 4.9���5.6; A 1 233���266 long, ring organ situated at 0.70���0.76 from base; BL 1 35���42 long; NB 33���37 long; NB / BL 1 0.83���0.90; BL 1 / A 2���4 0.80���0.88; A 2 28���35 long, length A 2 / width A 2 4.3���6.6 (3); BL 2 10���11; A 3 7���11 long; length A 3 / width A 3 3.6���4.4; A 4 5 long. Maxillary palp: basal segment 60���73 long, length / basal width 0.59���0.67; relative distance of CS 0.59���0.67. A 1 / PMx 3.64���4.08. Mandible (Fig. 22) 191���213 long. A 1 / Mn 1.17���1.26. Hypopharingeal complex: Ligula 108��� 145 long (Fig. 23), the outermost inner teeth slightly outcurved; paraligula bifid, 60���95 long; pecten hypopharyngis with 14���18 teeth; dorsomental teeth 5���7 (Fig. 24). Abdomen. Procercus 250���350 long (Fig. 25); L / W 3.00��� 3.50; with 13 setae 855���1050 long. Preanal seta 780��� 830 long. Posterior parapods: smallest claws simple curved (Fig. 26). Biology. The species A. vittigera was found in a wide range of standing water environments such as lakes, temporary pools and ���mallines��� (singular ���mall��n���). A ���mallin��� can be characterized as a humid meadow with a dense cover mainly dominated by Juncaceae, Cyperaceae and Gramineae. The mall��n soil contains a high percentage of organic matter and always associated with either surface water or ground water discharge. This kind of wetland in the Andes mountains is characterized by harsh environmental conditions, as the plant growth season is relatively short (abouth 4 months) and snow cover remains for about 6 months during the year (Raffaele 1996). Cladistic analysis. The data set analyzed under K = 5 to 16 yielded the same tree topology (Fig. 27) in each of the concavities (CI = 0.47, RI = 0.42). The tree derived from K = 5 (score = 30.37) showed the best character measure support calculated as absolute frequencies, frequency differences and absolute Bremer support. The best relative Bremer support measures were those of K = 7 (score = 29.7). The genus Alotanypus is a monophyletic group supported by the synapomorphies male AR of 1.8, male LR III of 0.68���0.76, female wing length of 3.30���4.20 mm, L / W of thoracic horn 3.00��� 4.60, relative position of LS 1 on segment VII of 0.51, relative position of LS 1 on segment VIII of 0.23���0.31, CI of 0.83���0.84, postnotal setae absent, tibial comb I present, claws spatulate (at least on pII). Alotanypus venustus is the basal species of the genus followed by A. dalyupensis and A. aris. The species A. vittigera is closely related with A. kuroberobustus and shares the characters male AR of 1.90���2.10, male wing length of 3.10���3.80, male LR II of 0.60���0.66, female LR II of 0.53���0.61, L / W of thoracic horn of 4.30���5.50, relative position of LS 1 on segment VII of 0.45���0.51, NB / BL 1 of 0.77 and curved apex of spur I on male. The clade [A. aris - A. vittigera - A. kuroberobustus] shares the characters female LR III of 0.63���0.71, DC 1 of 54��� 58 um long, thoracic horn of 524���680 um long, larval AR of 5.30���6.40, BL 1 / A 2���4 of 0.80���0.88, A 1 / Ring 0 of 0.70���0.76 and L / W PMx of 2.75���3.30. The clade [A. dalyupensis - A. aris - A. vittigera - A. kuroberobustus] shares the characters DC 1 of 78 um long, plastron plate / thoracic horn of 0.15���0.33, L / W of anal lobe of 1.82, L / W of A 2 of 4.50, relative position of CS on PMx of 0.50, mandible of 191���220 um long, A 1 / mandible of 1.19���1.29 and procercus of 296 um long. Guassutanypus oliveirai is the sister group of Alotanypus. This clade shares the presence of preepisternals, RM, FCu and MCu darkened veins on male and female, assymetrical neck position on seminal capsules, relative position of LS 1 on abdominal segment VII, horn sac of the thoracic horn not filling the entire horn lumen, number of teniated setae on segment VIII on pupa. This last clade is the sister group of the clade [P. d y a r i -D. alaskensis] by sharing characters: LR I on male; FCu vein darkened in male and female; length of DC 3 on pupa, A 1 / PMx, pecten hypopharnix and number of setae on procercus. The tribe Macropelopiini is monophyletic and it is supported by the synapomorphies male wing length of 3.00, male spur ratio of 0.28���0.42, female anal lobe length of 695���864, genital sac / anal lobe of 0.36���0.42, relative position of 0.16���0.17 for LS 1 and 0.25���0.26 for LS 2 on anal lobe, larval AR of 6.05 ���7.00, L / W PMx of 2.70, procercus length of 163���222, postorbitals multiserials, male spur thorn like. Spur teeth bigger than 15, outer fringed on anal lobe present and teniata setae on abdominal segment VII bigger than 5., Published as part of Siri, Augusto, Donato, Mariano, Orpella, Germ��n & Massaferro, Julieta, 2011, Alotanypus vittigera (Edwards) comb. nov.: adult redescription, immature description and a phylogenetic analysis of the genus (Diptera: Chironomidae: Tanypodinae), pp. 46-64 in Zootaxa 2795 on pages 54-61, DOI: 10.5281/zenodo.204609, {"references":["Edwards, F. W. (1931) Chironomidae. In: Diptera of patagonia and South Chile. Part II, Nematocera. Trustees of the British Museum (Natural History), London, pp. 233 - 331.","Spies, M. & Reiss, F. (1996) Catalog and bibliography of Neotropical and Mexican Chironomidae (Insecta, Diptera). Spixiana, Supplement, 22, 61 - 119.","Raffaele, E. (1996) Relationships between seed and spore banks and vegetation of a mountain flood meadow (mallin) in Patagonia, Argentina. Wetlands, 16, 1 - 9."]}
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- 2011
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- View/download PDF
34. Historia ambiental postcolombiana del Lago Petén Itzá, Guatemala
- Author
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Pérez, Liseth, Bugja, Rita, Massaferro, Julieta, van Geldern, Robert, Steeb, Philip, Frenzel, Peter, Brenner, Mark, Scharf, Burkhard, and Schwalb, Antje
- Subjects
purl.org/becyt/ford/1 [https] ,purl.org/becyt/ford/1.5 [https] ,FRESHWATER OSTRACODES ,CHIRONOMIDS ,EUTROPHICATION ,Otras Ciencias de la Tierra y relacionadas con el Medio Ambiente ,LAKE LEVEL ,LAGO PETÉN ITZÁ ,GUATEMALA ,GEOCHEMISTRY ,CIENCIAS NATURALES Y EXACTAS ,Ciencias de la Tierra y relacionadas con el Medio Ambiente - Abstract
Two ~40-cm-long sediment cores, PI-SC-1-10m and PI-SC-2-40m, were recovered at 10 and 40 m water depth, respectively, from Lago Petén Itzá, in the Department of Petén, northern Guatemala. The cores span the last ~525 years of sediment accumulation in the basin. This study explores lake level and trophic state changes that Lago Petén Itzá has experienced since European contact in the early 1500s. We inferred past environmental variability using changes in sediment geochemistry and fluctuations in relative species abundances of ostracode and chironomid fossil assemblages. Changes in concentrations of organic matter (OM), carbonate, total carbon (TC), total nitrogen (TN), C/N ratios, bromine (Br), and faunal relative abundances were used to infer changes in the trophic status of the lake. Cultural eutrophication began in the 1930s, and anthropogenic impact increased significantly after ~1970. Higher linear sedimentation rates, up to 9.1 mm yr-1, began recently. They are attributed to increases in riparian settlement, deforestation and associated land use changes, which led to accelerated soil erosion. An ostracode-based transfer function was applied to assemblages in core PI-SC-1-10m, which enabled us to identify periods when lake level fluctuated. Such historical fluctuations in lake levels were driven primarily by changes in rainfall. Past lake levels can be summarized as follows: (1) fluctuating, high lake levels from ~1550s to the 1730s and from the early 1940s to 2005, and (2) stable, lower lake levels from about 1750 to the early 1900s. Higher relative abundance of the ostracode Physocypria globula and higher rubidium (Rb) concentrations indicate higher lake levels than today. Chironomids also show sharp fluctuations along the cores that could be related to water level changes. The presence of chironomid assemblages Chironomus, Procladius, and Einfeldia from 1960–2000 AD shows high productivity levels. The Lago Petén Itzá sediment record indicates a generally arid Little Ice Age (LIA), with exceptions around 1580 and 1650 when high lake levels similar to those of the 20th century, i.e. ~5 m higher than today, indicate more humid conditions. Dos núcleos de sedimentos PI-SC-1-10m y PI-SC-2-40m de 40 cm de largo fueron extraídos bajo un tirante de agua de 10 y 40 m en el Lago Petén Itzá, Departamento de Petén, en el norte de Guatemala. Los núcleos abarcan los pasados ~525 años de acumulación de sedimentos en el lago. Este estudio explora los cambios en los niveles del lago y cambios en el estado trófico que el Lago Petén Itzá ha sufrido desde el contacto Europeo a inicios del siglo XVI. Hemos inferido la variabilidad ambiental del pasado utilizando cambios en la geoquímica de los sedimentos y en las fluctuaciones de las abundancias relativas de las especies de comunidades de ostrácodos y quironómidos. Cambios en las concentraciones de materia orgánica (MO), carbonato, carbono total (CT), nitrógeno total (NT), bromo (Br), en la proporción C/N y cambios en la abundancia relativa faunística fueron utilizadas para inferir cambios en el estado trófico del lago. La eutroficación cultural inició desde la década de 1930, y el impacto antropogénico ha aumentado significativamente desde ~1970. Una alta tasa de sedimentación linear de hasta 9.1 mm yr-1 ha iniciado recientemente. Esto se atribuye a un incremento en la ocupación ribereña del lago durante las últimas décadas, la cual está asociada a cambios de uso de la tierra y ha llevado a una acelerada deforestación y erosión de los suelos. Una función de transferencia basada en ostrácodos fue aplicada a las comunidades del núcleo PI-SC-1-10m pudiendo identificar períodos durante los cuales el nivel del lago ha fluctuado unos ~5 m. Estas fluctuaciones históricas en el nivel del lago fueron causadas principalmente por cambios en la precipitación pluvial. Los niveles pasados del lago se resumen de la siguiente forma: (1) niveles altos fluctuantes entre las décadas de 1550 y 1730 y de los primeros años de la década de 1940 a 2005, y (2) niveles bajos estables de 1750 a la década de 1900. Una abundancia relativa alta de Physocypria globula y altas concentraciones de rubidio (Rb) indican niveles del lago más altos a los actuales. Quironómidos indican fluctuaciones a lo largo de los núcleos que pueden estar relacionadas con cambios en los niveles del lago. La presencia de las comunidades de quironómidos Chironomus, Procladius, y Einfeldia de 1960–2000 AD indica niveles altos de productividad. El registro sedimentario del Lago Petén Itzá indica en general una árida Pequeña Edad de Hielo (PEH), con excepción de los años alrededor de 1580 y 1650, cuando los niveles del lago fueron altos y similares a los del siglo XX, i.e., unos ~5 m más altos que los actuales, lo que indica condiciones más húmedas. Fil: Pérez, Liseth. Technische Universität Braunschweig. Institut für Umweltgeologie; Alemania Fil: Bugja, Rita. Technische Universität Braunschweig. Institut für Umweltgeologie; Alemania Fil: Massaferro, Julieta. Administracion de Parques Nacionales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: van Geldern, Robert. Friedrich-Alexander-Universität Erlangen-Nürnberg. Angewandte Geowissenschaften. GeoZentrum Nordbayern; Alemania Fil: Steeb, Philip. Technische Universität Braunschweig. Institut für Umweltgeologie; Alemania Fil: Frenzel, Peter. Universitat Jena; Alemania Fil: Brenner, Mark. University of Florida. Department of Geological Sciences & Land Use and Environmental Change Institute; Estados Unidos Fil: Scharf, Burkhard. Technische Universität Braunschweig. Institut für Umweltgeologie; Alemania Fil: Schwalb, Antje. Technische Universität Braunschweig. Institut für Umweltgeologie; Alemania
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- 2010
35. Assessing the performance of macroinvertebrate metrics in the Challhuaco-Ñireco System (Northern Patagonia, Argentina)
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Mauad, Melina, primary, Miserendino, M. Laura, additional, Risso, Miguel A., additional, and Massaferro, Julieta, additional
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- 2015
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36. Apedilum griseistriatum comb. nov., placement of Chironomus (Polypedilum) griseistriatum (Diptera, Chironomidae)
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Donato, Mariano, primary, Siri, Augusto, additional, Massaferro, Julieta, additional, and Brooks, Stephen J., additional
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- 2015
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37. Parakiefferiella claviculata Edwards 1931, comb. n
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Massaferro, Julieta, Donato, Mariano, and Brooks, Stephen J.
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Insecta ,Arthropoda ,Diptera ,Animalia ,Biodiversity ,Parakiefferiella ,Parakiefferiella claviculata ,Chironomidae ,Taxonomy - Abstract
Parakiefferiella claviculata (Edwards, 1931), comb. n. Spaniotoma (Eukiefferiella) claviculata Edwards, 1931: 291. Parakiefferiella lagorum Wiedenbrug & Andersen, 2002: 120, syn. n. The measurements obtained by the study of the type material were carefully compared with the description of P. la go ru m made by Wiedenbrug & Andersen (2002) and it fits exactly with all of them. Therefore, a re-description or an emendation of that diagnosis is not needed. Material examined: Holotype male (NHM), Argentina, Terr. R��o Negro, L. Nahuel Haupi Eastern End, 28 / 31 ���X��� 1926, leg. F. & M. Edwards, B.M. 1927 ��� 63; paratype male (NHM), same data as holotype., Published as part of Massaferro, Julieta, Donato, Mariano & Brooks, Stephen J., 2009, New placement for Spaniotoma (Eukiefferiella) claviculata Edwards, 1931 (Diptera: Chironomidae), pp. 67-68 in Zootaxa 2125 on page 67, DOI: 10.5281/zenodo.188250, {"references":["Wiedenbrug, S. & Andersen, T. (2002) New species of Parakiefferiella Thienemann, 1936 from South America (Chironomidae, Orthocladiinae). Studies on Neotropical Fauna and Environment, 37 (2), 119 - 132"]}
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- 2009
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38. Biodiversidad de insectos acuáticos en Patagonia Norte, Argentina: programa Iniciativa DARWIN
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Brooks, Stephen J., Hernández, Luis M., Massaferro, Julieta, Spinelli, Gustavo Ricardo, and Penn, Malcolm
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Ciencias Biológicas ,purl.org/becyt/ford/1 [https] ,Aquatic insects ,Patagonia ,Zoología ,Insectos acuáticos ,Bioquímica y Biología Molecular ,purl.org/becyt/ford/1.6 [https] ,Darwin inititative ,CIENCIAS NATURALES Y EXACTAS ,Iniciativa Darwin - Abstract
Este proyecto fue financiado durante un período de tres años, desde septiembre de 2006 a través de la Iniciativa Darwin del gobierno Británico. El objetivo de este trabajo es el estudio de los insectos acuáticos del Parque Nacional Nahuel Huapi (PNNHP), Patagonia, Argentina. El parque incluye una gran variedad de hábitats que comprenden arroyos, ríos y lagos los cuales se distribuyen desde el bosque siempreverde frío, hasta la zona árida de estepa. Todo el material será identificado y depositado en las colecciones del Museo La Plata y el Museo de Historia Natural de Londres. Los fondos de la Iniciativa Darwin han sido utilizados para equipar un laboratorio de biodiversidad en las oficinas del PNNHP en Bariloche y la estación de investigación en Puerto Blest. Toda la información de los insectos acuáticos y las distintas formaciones vegetales donde éstos se han encontrado, se incluirá en una base de datos (la primera de su tipo en Patagonia) que utilizará la metodología GIS para analizar patrones de distribución de las especies en el parque. En estos momentos se están produciendo varias guías de campo para identificar los insectos acuáticos del PNNHP. Es nuestro deseo que los resultados obtenidos en este proyecto, contribuyan a la conservación de los sistemas acuáticos en Argentina y América del Sur., This project was funded from September 2006 for three years by the British Government's Darwin Initiative programme. The focus of our project is the study of aquatic insects from Nahuel Huapi National Park (NHNP) in Patagonia, Argentina. The park includes a wide range of wetlands, including montane streams, lowland lakes and marshes, distributed within temperate rainforest and arid steppe. The material will be identified and stored in a fully referenced and accessible collection at La Plata Museum and the Natural History Museum, London. Darwin Initiative funding has been used to equip a biodiversity laboratory at National Park Headquarters in Bariloche and also a field station at Puerto Blest. Information on the insect species in NHNP will be entered into a GIS database, together with a vegetation classification and wetland characteristics, to model freshwater insect data spatially and create a biodiversity database, the first of its kind in Patagonia. We hope that the experiences we gain during the project, the insect collections and databases, the publications, and the many other products, will be used to further enhance wetland conservation throughout Argentina and southern South America., Facultad de Ciencias Naturales y Museo
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- 2009
39. Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera) de la Patagonia
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Donato, Mariano Humberto, Massaferro, Julieta, and Brooks, Stephen J.
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Diversidad ,Diversity ,Otras Ciencias Biológicas ,Chironomidae ,diversity ,Ciencias Biológicas ,purl.org/becyt/ford/1 [https] ,lcsh:Zoology ,diversidad ,Patagonia ,Ciencias Naturales ,lcsh:QL1-991 ,purl.org/becyt/ford/1.6 [https] ,CIENCIAS NATURALES Y EXACTAS - Abstract
La familia Chironomidae (Diptera: Nematocera) es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK) y del material de colección del Museo de La Plata (Argentina). En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58) y machos y hembras (n=43), ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo., The Chironomidae (Diptera: Nematocera) family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK) and the collection material from Museo de La Plata (Argentina). Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known genera from South America, 53 are present in the studied area. Aproximately 20 % of the genera recorded from Patagonia are endemic and 7 of them have transantarctic relationships. In Patagonia there are 177 species of Chironomidae, out of which 98% are endemic, 3 % are considered nomina dubia and ca. 17 % requires revision since their systematic position is doubtful. The original descriptions of the chironomid species from Patagonia are based mainly on males (n=58) and males and females (n=43) both amounting to 57 % of the total, the rest of the species have been described using different combinations of stages from their life cycle., Facultad de Ciencias Naturales y Museo, Consejo Nacional de Investigaciones Científicas y Técnicas
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- 2009
40. Bioindicators of climate and trophic state in lowland and highland aquatic ecosystems of the Northern Neotropics
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Pérez, Liseth, primary, Lorenschat, Julia, additional, Massaferro, Julieta, additional, Pailles, Christine, additional, Sylvestre, Florence, additional, Hollwedel, Werner, additional, Brandorff, Gerd Oltmann, additional, Brenner, Mark, additional, Islebe, Gerald, additional, Lozano, María Del Socorro, additional, Scharf, Burkhard, additional, and Schwalb, Antje, additional
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- 2013
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41. Using a newly developed chironomid transfer function for reconstructing mean annual air temperature at Lake Potrok Aike, Patagonia, Argentina
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Massaferro, Julieta, primary and Larocque-Tobler, Isabelle, additional
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- 2013
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42. The dynamics of chironomid assemblages and vegetation during the Late Quaternary at laguna Facuil, Chonos Archipelago, south Chile
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Massaferro, Julieta, Brooks, Stephen J, Haberle, Simon, Massaferro, Julieta, Brooks, Stephen J, and Haberle, Simon
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We compare high-resolution pollen and chironomid records from the last 15,000 yr in Laguna Facil, southern Chile. Major vegetation and chironomid changes are recorded between ca 14,900 and 14,700 cal. yr BP. During the Lateglacial, changes in the chironomid stratigraphy lag behind changes in the pollen stratigraphy suggesting that the chironomids are responding to changes in the tree canopy or in soil chemistry brought about by vegetational development. At about 7200 cal. yr BP there is a change in the chironomid stratigraphy in advance of changes in the vegetation. This suggests that the response is to regional climatic change. The relatively close correlation of the chironomid and pollen stratigraphies with changes in charcoal concentrations also implicates the importance of fire and/or vulcanism in influencing the dynamics of forest and limnological systems. There is no clear evidence of cooling during the Younger Dryas chronozone in Laguna Facil.
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- 2005
43. CHIRONOMID RESEARCH IN NORTHERN PATAGONIA
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Mariano, Donato, primary, Massaferro, Julieta, additional, and Brooks, Stephen J., additional
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- 2009
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44. The water chemistry of some shallow lakes in Northern Patagonia and their nitrogen status in comparison with remote lakes in different regions of the globe
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ROGORA, Michela, primary, MASSAFERRO, Julieta, additional, MARCHETTO, Aldo, additional, TARTARI, Gabriele, additional, and MOSELLO, Rosario, additional
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- 2008
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45. Structure of chironomid assemblages (Diptera: Chironomidae) in elevational gradients: tools for studying climate and environmental changes
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Motta, Luciana Maria, Massaferro, Julieta, and Ruggiero, Adriana
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Ciencias Biológicas ,purl.org/becyt/ford/1 [https] ,FACTORES AMBIENTALES ,LAGUNAS ,LAGOS ,META-ANÁLISIS ,Otros Tópicos Biológicos ,QUIRONÓMIDOS ,GRADIENTES ALTITUDINALES ,purl.org/becyt/ford/1.6 [https] ,CIENCIAS NATURALES Y EXACTAS - Abstract
Se estudió la influencia de factores ambientales sobre la composición taxonómica, riqueza y abundancia de quironómidos, en lagos y lagunas en gradientes altitudinales a diferentes escalas espaciales. A escala global, un enfoque meta-analítico evidenció que el patrón altitudinal en la riqueza de especies presenta múltiples formas, predominando una forma no lineal, la cual sugiere que la riqueza de quironómidos se mantiene alta en lagos situados en elevaciones bajas a intermedias, decreciendo abruptamente a altas elevaciones (forma “meseta”). Además, se observó que principalmente los factores metodológicos, y marginalmente los biogeográficos afectaron la determinación de los patrones. A escala regional, se estudiaron los ensambles de quironómidos de la región andino-patagónica, confirmando que la temperatura es la variable de mayor influencia sobre la composición y riqueza. La existencia de taxones característicos para lagos por encima y por debajo de la línea de vegetación sugiere que el cambio en la vegetación terrestre que ocurre en la transición del ambiente Altoandino a los bosques Subantárticos, juega un rol importante. De forma concordante a lo observado a escala global, el patrón de riqueza a nivel regional presentó una forma de tipo “meseta”. A escala local, un estudio realizado en ocho lagunas de Patagonia norte, mostró cambios altitudinales en la composición de ensambles que se asociaron con la vegetación y con características morfológicas y biológicas de las lagunas. Las variaciones en la riqueza de géneros y abundancia de individuos se asociaron a distintas variables, siendo la materia orgánica la variable de mayor importancia. Los resultados de esta tesis muestran que no sólo la temperatura, sino otras variables y sus múltiples interacciones, modelan la estructuración de los ensambles de quironómidos en lagos de montaña, lo cual tiene importantes implicancias en la Paleoecología y en estudios de cambio ambiental y climático. This thesis studied the influence of environmental factors on the taxonomic composition, richness and abundance of chironomids in lakes in altitudinal gradients at different spatial scales. At a global scale, a meta-analytic approach evidenced that altitudinal patterns of chironomid richness can display multiple forms, with a predominance of a non-linear shape, suggesting that chironomid richness remains high in lakes located at low to mid elevations, decreasing abruptly at higher elevations (“low plateau” shape). In addition, mainly methodological and marginally biogeographic factors affected the determination of the patterns. At a regional scale, assemblages of the andean-patagonian region were studied, confirming that temperature is the most influential factor on the composition and richness of chironomid assemblages. The existence of indicator taxa of lakes situated above and bellow the treeline suggests that changes in terrestrial vegetation ocurring in the transition from the Altoandino environment to the Subantarctic forests, played an important role. Accordingly, the elevational richness pattern at a regional scale presented a “low plateau shape”. At local scale, a detailed study of eight lakes in northern Patagonia showed altitudinal changes in assemblages composition that were associated with vegetation and with morphological and biological characteristics of the waterbodies. Variations in genus richness and abundance of individuals were associated with different environmental variables and habitats, being organic matter content the most important variable. This thesis shows that not only temperature, but other environmental variables and their multiple interactions, model the structuring of chironomid assemblages in mountain lakes. These findings have important implications in Paleoecology and studies of environmental and climate change. Fil: Motta, Luciana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Administración de Parques Nacionales; Argentina
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- 2017
46. Estudio de los quironómidos subfósiles como indicadores de las variaciones en el clima regional a ambos lados de la Diagonal Árida (Patagonia y Pampa) en los últimos 1000 años
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Montes de Oca, Fernanda, Massaferro, Julieta, and Laprida, Cecilia
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Lagunas ,purl.org/becyt/ford/1 [https] ,purl.org/becyt/ford/1.5 [https] ,Otras Ciencias de la Tierra y relacionadas con el Medio Ambiente ,Diagonal Arida ,CIENCIAS NATURALES Y EXACTAS ,Proxy ,Chironomidae ,Ciencias de la Tierra y relacionadas con el Medio Ambiente - Abstract
Las reconstrucciones paleoambientales y paleoclimáticas a partir de indicadores (proxies) archivados en los sedimentos acumulados en los lagos, permiten conocer la dinámica de estos ecosistemas y la respuesta de los mismos frente a la variabilidad ambiental pasada a distintas escalas que van desde milenios a decenios de años. Los cambios en el clima y la actividad antrópica son las principales forzantes de cambio en los ambientes lacustres. Los restos subfósiles de las larvas de quironómidos (Diptera: Chironomidae) son útiles paleoindicadores (paleoproxies) biológicos porque responden a los cambios en las condiciones ambientales del pasado. Además, son utilizados en estudios multiproxy ya que proveen información independiente que, combinada con otros proxies, genera una respuesta integrada de las condiciones ambientales que reinaron en el pasado. Los últimos estudios paleolimnológicos del norte de la Patagonia y centro de Argentina indican la existencia de un contraste regional en cuanto a precipitaciones y temperaturas que se evidencia a lo largo de la Diagonal Árida Argentina. Esta franja escinde dos grandes conjuntos de sistemas lacustres con diferente regulación hídrica y con respuesta paleohidrológicas contrarias frente a fases climáticas conocidas, como por ejemplo la Pequeña Edad de Hielo. El objetivo principal de esta tesis fue estudiar las variaciones ambientales (naturales y antrópicas) registradas durante los últimos ca. mil años a ambos lados de la Diagonal Árida (DA) con el fin de aportar nuevas evidencias del contraste climático regional (anti-fase). Para ello se estudiaron y compararon los ensambles de quironómidos subfósiles contenidos en secuencias sedimentarias lacustres ubicadas a un lado y otro de la DA. Las secuencias sedimentarias seleccionadas fueron Laguna la Barrancosa (37° S) en el suroeste de la provincia de Buenos Aires, región Pampeana y Lagunas Verde y Toncek (41° S) en el noroeste de Patagonia. Para reconstruir la historia ambiental de cada laguna y relacionarla con los eventos climáticos de los últimos 1000 años, se incorporó información provista por otros proxies sedimentarios como los pigmentos fotosintéticos fósiles (derivados de clorofila y carotenoides totales), la materia orgánica y en los casos que fue posible, información geoquímica (N, C, S) y de ostrácodos. Los resultados obtenidos en cada secuencia sedimentaria a partir de los indicadores estudiados permitieron definir diferentes intervalos de tiempo o períodos con distintas condiciones ambientales. Se definieron 3 períodos climáticos en la historia ambiental de la laguna La Barrancosa: Un primer período oscilante entre condiciones secas y húmedas, entre ~610-1278 AD, coincidentes en parte con la Anomalía Climática Medieval; un segundo período, entre ~1278-1947 AD dominado por condiciones más secas asociada al período la Pequeña Edad de Hielo; y finalmente un tercer período, el más actual, entre 1947-2012 AD, dominado por condiciones húmedas en su primera parte y coincidente con el Salto Climático del siglo XX. La dinámica ambiental, en la historia más reciente de la laguna ubicada en el suroeste de la provincia de Buenos Aires, estuvo marcada por una fuerte impronta de las actividades antrópicas en la región y por el incremento de las precipitaciones con inicio en la década del 1940. Durante el siglo XV, se infirió el establecimiento de un ambiente temporal sub-salino y un balance hidroclimático negativo. Durante la década de 1970, La Barrancosa se habría establecido como una laguna permanente en estado trófico “claro”, asociado al incremento en las precipitaciones regionales (Salto Climático del siglo XX) y al cambio ecológico regional que impulsó el cambio en los patrones de circulación y precipitaciones de esa región. Desde 1990, los procesos de eutrofización en la laguna se aceleraron, probablemente como consecuencia del incremento en la actividad agrícola que registró el área y por el uso de técnicas agrícolas modernas basadas en el uso intensivo de fertilizantes y pesticidas. Otras actividades como la siembra de la especie Odontesthes bonariensis, podría haber favorecido los procesos de eutrofización en la laguna. En la Laguna Verde se definieron 3 períodos climáticos diferentes: el primero de ellos entre ~1561-~1670 AD dominado por condiciones frías y húmedas coincidente, en parte, con el transcurso de la Pequeña Edad de Hielo en Patagonia; un segundo período ~1670- ~1878 AD dominado en su última parte por condiciones mayormente secas; y por último el tercer período, el más actual entre ~1878-2012 AD coincidente en su última parte con el calentamiento global del siglo XX registrando condiciones climáticas más cálidas que en el período anterior. Por último el registro sedimentario de la laguna Toncek, permitió definir 2 períodos climáticos, el primero de ellos (~1644-1960 AD) dominado mayormente por condiciones frías. En la primera parte de este período y hasta ~ 1870 AD habrían dominado condiciones húmedas y frías coincidente también con el transcurso de la Pequeña Edad de Hielo. Y un segundo período 1960 AD-2012 AD, coincidente con el calentamiento global del siglo XX que habría permitido un leve incremento en la productividad de la lagunas. Las importantes diferencias en cuanto a riqueza y abundancia que se observan en los registros de quironómidos subfósiles de las lagunas Verde y Toncek, se relacionan principalmente a condiciones locales (ubicación por encima y por debajo de la línea de crecimiento arbóreo, tipo de cuenca cerrada o abierta, presencia o ausencia de macrófitas) que, entre otras diferencias, definen la contribución de material orgánico, con gran impacto en la dinámica del ambiente y en la composición faunística. En términos generales, las paleocomunidades de quironómidos de cada ambiente reflejaron cambios importantes en su composición y abundancia frente a eventos climáticos, hidrológicos y antrópicos ocurridos durante los últimos 1000 años en el sudoeste de la provincia de Buenos Aires y últimos 500 años en el sector noroeste de Patagonia. Sin embargo, en todos los registros los cambios más notorios se evidenciaron en los últimos 100 años de la historia evolutiva de cada laguna y particularmente en los ambientes del Noroeste de Patagonia por el impacto recurrente de caída de cenizas en el área, proveniente del área cercana chilena durante los últimos 200 años. Las reconstrucciones paleoambientales efectuadas a un lado y otro de la DA permitieron observar patrones de respuesta opuestos en cuanto a cambios en los niveles de agua y productividad durante el período climático frío denominado Pequeña Edad de Hielo. Los cambios hidroclimáticos de los últimos 1000 años, fueron más notorios en el ambiente pampeano, Laguna La Barrancosa, ubicado en el suroeste de la provincia de Buenos Aires. Por otro lado en todos los registros, se observaron cambios de productividad en los últimos 100 años, los cuales estarían asociados a una combinación de 1) aumento de temperatura durante el calentamiento global del siglo XX (desde ~1900) y 2) incremento en las actividades antrópicas (con mayor evidencia en la región pampeana) combinadas con las características propias y locales de cada ambiente (régimen hídrico, cuenca, procesos intrínsecos). The paleoenvironmental and paleoclimatic reconstructions based on proxies from lake sediments provide information about the dynamic of lakes and the responses of these ecosystems to past climatic variability, at different time scales from millennia to decades. Changes in climate and anthropogenic activities are the main drivers of changes in aquatic ecosystems. Subfossil chironomids (Diptera: Chironomidae) are useful paleoindicators due to their specific response to past environmental conditions. In addition, they can be used in multiproxy studies as an independent information of past environmental conditions. Last paleoclimate records from northern of Patagonia and central of Argentina indicated a regional contrast related to precipitations and temperature along the so call “Diagonal Arida” Argentina. This narrow climatic band distinguishes twogroups of lakes systems with different hydrological regime and with diverse paleohydrological responses to short climatic phases such as the Little Ice Age. The aim of this Thesis was to study the environmental variations (natural and anthropic) recorded during the last ca. 1000 years on both sides of the “Diagonal Arida” (DA) in order to provide new evidences of the asynchronous regional climate (anti-phase). To meet the objectives, chironomid assemblages from lakesla Barrancosa (37 °S), southwest of the province of Buenos Aires (Pampean region) and from lakesVerde and Toncek) (41 °S) in northwestern Patagonia were analyzed and compared to reconstruct the environmental history of each lake and the dominant climatic phases during the last 1000 years. Complementary information fromgeochemical parameters such as fossil pigments (CD, TC), organic matter and, when it was available, nutrients and ostracods were used to reconstruct the paleolimnological conditions of the each lake. Results from the multiproxy analysis from each sedimentary sequence, allowed to detect different periods associated each one to different environmental conditions.Three climatic periods were defined on thepaleoenvironmental history of lake La Barrancosa. The first period,between ~610-1278 AD, dry/ wet climatic fluctuations were inferred. The last part of this period was associated to the Warm Medieval Anomaly. The second period, between ~1278-1947 AD, a negative hydrological balance was detected which was associated to the Little Ice Age. Finally, the third period, between 1947-2012 AD, wet climatic conditions were inferred associated to the increase of regional precipitation since 1940 ca. The environmental dynamics oflakeLa Barrancosa reveals a hydroclimatic variability and human impact trends in the area during the 20th century. During the 15th century, the Barrancosa sedimentary record allowed to infer negative hydrological balance and theestablishment of a temporary, sub-saline environment. An ecological regional shiftat the 1970s marks the onset of the mid-20th century climatic amelioration driven by changes in circulation patterns and precipitations, allowed the establishment of a clear waters shallow lake. Since 1990, the eutrophication processes were accelerated, probably as a consequence of the great increase in the agriculture around the lake and the transition from the traditional to modern techniques based on extensive use of fertilizers and pesticides in the region. Other activities such as the introduction of the fish species Odontesthes bonariensis, could have favoured eutrophication processes in this lake.The subfossil chironomid records from lakes Verde and Toncek documented changes in the assemblage composition and absolute abundance in the last ca. 500 yrs in response to a combination of diverse environmental drivers.Three climatic periods were defined in the paleoenvironmental history of lake Verde. The first period, between 1561-~1670 AD was dominated by cold and wet climatic conditions and associated, in part, with the Little Ice Age; a second period, between ~1670-~1878 AD, was dominated dry climatic conditions mainly in the last part of the period and, a third period, between ~1878-2012 AD, dominated by warm climatic conditions associated with the current global warmingperiod. The paleolimnological record of lake Toncek was divided in two climatic periods. The first period, between ~1644-1960 AD, was dominated mostly by cold conditions coincident with Little Ice Age, a second period, between 1960 AD and 2012 AD, was synchronous to the current general trend of increasing temperatures associated with current global warmingperiod. These climatic conditions allowed more productive conditions. Ash falls from nearby volcanoes appear to be one of the factors of change in the chironomid assemblages mainly in lake Toncek although in the last ca. 50 years, climate warming and human impacts have also been responsible for changes in the midge communities of each lake. Superimposed to volcanism, others environmental factors interplay in the lake ecosystem, such as hydrology, watershed characteristics and quality and quantity of organic matter as key to understanding changes in the composition and diversity of biota in remote lakes through time.Summarizing, the paleocommunities of chironomids of each environment studied reflected important changes in its composition and abundance related to climatic, hydrological and anthropic drivers acting during the last 1000 years in the southwest of the province of Buenos Airesand, in the last 500 years in the northwest of Patagonia although the most important changes, in the last two lakes were evident in the last 100 years. During the last 200 years, the impact of volcanic tephra from nearby Chilean volcanoes caused importantchange to the chironomid records from the northern patagonian lakes. The paleoenvironmental reconstructions from the studied lakes allowed to detect different response patterns in terms of water level changes, climate and productivity changes at both sides of the “Diagonal Arida” especially during the so called LIA. Hydroclimatic changes during the last 1000 years were more evident in the Pampas lake, La Barrancosa. On the other hand, in all the records, productivity changes were observed in the last 100 years which could be linked to 1) general trend of increasing temperatures observed in South America since 1900AD and 2) to anthropic drivers (mainly at lake La Barrancosa) combined with local environmental characteristics such as hydrology, catchment area,intrinsec process, between others. Fil: Montes de Oca, Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Administración de Parques Nacionales. Delegación Regional Patagonia; Argentina
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- 2017
47. Quironómidos (Insecta: Díptera: Chironomidae) subfósiles como indicadores de cambios climáticos y eventos geológicos de disturbio en sedimentos de Lagos andinos de Patagonia Norte
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Serra, Maria Noel, Massaferro, Julieta, and Villarosa, Gustavo
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Ciencias Biológicas ,purl.org/becyt/ford/1 [https] ,Cambio Climático ,Tefra ,Otros Tópicos Biológicos ,Paleolimnologia ,purl.org/becyt/ford/1.6 [https] ,CIENCIAS NATURALES Y EXACTAS ,Quironómidos - Abstract
El Período Cuaternario, se caracterizó por ser un período con una gran actividad glaciarintercalada con períodos cálidos, provocando oscilaciones climáticas de gran amplitud, lascuales se combinaron con oscilaciones cíclicas de tipo seco-húmedo. En el último milenio sereconocen dos grandes cambios climáticos de poca amplitud a nivel mundial: la PequeñaEdad del Hielo (PEH), período frío, con baja actividad solar y alta actividad volcánica (1300-1900 años AD); y la Anomalía Climática Medieval (ACM, antiguamente denominado PeríodoCálido Medieval; 800 - 1300 años AD). El sur de Sudamérica, y en particular Patagonia, es unsitio valioso para el estudio de cambios ambientales, especialmente paleoambientales, por serla única masa continental ubicada en latitudes medias-altas en el Hemisferio Sur, por lapresencia de numerosos lagos formados durante la última glaciación del Cuaternario, una granvariedad de bosques y ambientes lacustres, con un marcado gradiente altitudinal y latitudinaly con cambios bióticos y sedimentarios en las últimas décadas. El estudio de la limnología delpasado (paleolimnología), analizando las características físicas, químicas, mineralógicas y labiota fósil preservada en los sedimentos lacustres, es de gran importancia en estudios decambios ambientales. Por otro lado, los estudios tefroestratigráficos y tefrocronológicos sonde gran importancia para reconstruir la ocurrencia de eventos volcánicos del Holoceno, loscuales pueden tener impactos significantes en los ecosistemas modificando las tasas desedimentación, aportes de nutrientes, penetración de luz, propiedades fisicoquímicas,limnobiota y afectando los organismos que viven en los ambientes acuáticos.El objetivo general de este proyecto es estudiar la respuesta de los ensambles dequironómidos (Insecta: Díptera: Chironomidae) a los cambios climáticos y ambientales,incluyendo los originados por disturbios naturales (volcanismo), ocurridos en la regiónnorpatagónica en el último milenio. En particular se propone estudiar dos ambientesubicados en la zona oeste del Parque Nacional Nahuel Huapi y dos ambientes comprendidosentre la ciudad de Esquel y el Parque Nacional Los Alerces, para evaluar sus efectos sobrelas comunidades de quironómidos.Se seleccionaron cuatro sitios (Lagunas La Zeta, Terraplén y El Trébol, y Brazo Blesten el lago Nahuel Huapi) situados entre los 42° 59? - 41° 01? S y los 71° 31? - 71° 50? O, seeligieron por ser ambientes prístinos, de similar tamaño, profundidad, cuencas relativamenteplanas y sin afluentes importantes, estar en zonas con numerosos eventos de caída de cenizasvolcánicas registrados. Se extrajeron testigos sedimentarios de los cuatro sitios y se lossubmuestreó para la realización de dataciones, análisis de materia orgánica, quironómidos ytefras. Las cronologías se elaboraron a partir de dataciones con 210Pb y 14C, cubriendo unregistro de episodios climáticos/ambientales hasta aproximadamente 1000 años atrás.En la laguna La Zeta se encontraron un total de 2098 quironómidos, representado por 17morfotaxa, pertenecientes a las subfamilias Chironominae, Orthocladiinae, Tanypodinae yPodonominae, con la subfamilia Chironomidae como dominante. El número de individuosvarió entre 105 y 23 por centímetro, con Tanytarsini 1B como taxón más abundante, seguidopor Cricotopus y Chironomus, y los taxones con abundancias relativas totales menores a 1 %fueron Dicrotendipes, Glyptotendipes, Gymnomectrionemus, Smittia, Paratanytarsus yParochlus. En la laguna Terraplén se encontraron 8006 quironómidos, compuesto por 18géneros pertenecientes a las subfamilias Chironominae, como predominante, Orthocladiinae yTanypodinae. El número de individuos por centímetro varió entre 295 y 39, con Tanytarsini1B como taxón más abundante, seguido por Ablabesmyia y Chironomus, y los taxones conabundancias relativas totales menores a 1 % fueron Apsectrotanypus, Alotanypus, Cricotopus,Cryptochironomus, Eukiefferiella, Labrundinia, Limnophyes, Parachironomus,Paratanytarsus y Polypedilum. En la laguna El Trébol se encontraron 4757 quironómidos,representado por 20 morfotaxas, pertenecientes a las subfamilias Chironominae, dominante alo largo de todo el testigo, Tanypodinae y Orthocladiinae. El número total de individuos porcentímetro varió entre 209 y 9, con Tanytarsini 1B como taxón más abundante, seguido porDicrotendipes, Chironomus y Ablabesmyia, y los taxones con abundancias relativas totalesmenores a 1 % fueron Corynoneura, Eukiefferiella, Gymnomectrionemus, Parachironomus,Paratanytarsus, Cryptochironomus, Cricotopus y Polypedilum En el Brazo Blest seencontraron un total de 185 quironómidos pertenecientes a 27 morfotipos, de las familiasChironominae, Orthocladiinae, ambas predominantes a lo largo de todo el testigo,Tanypodinae y Podonominae.Se observaron cambios climáticos, variaciones en la productividad del sistema y en lascomunidades de quironómidos relacionadas con la caída de cenizas volcánicas. En la lagunaEl Trébol se observa un clima húmedo y frío desde el año 700 AD hasta el 1300 AD, seguidopor un clima húmedo y cálido hasta el año 1400 AD, a partir del cual cambia a un clima secoy cálido hasta la actualidad. En el Brazo Blest también se observa este clima seco y cálidodesde el año 1790 AD a la actualidad, con grandes aportes de aguas glaciarias provenientesdel glaciar Frías. En las lagunas La Zeta y Terraplén, se observa un incremento de laproductividad desde el año 413 aC hasta la actualidad, mientras que en el Brazo Blest seobserva un cambio de materia autóctona a alóctona en el año 1950 AD. Los ensambles dequironómidos se vieron modificados por las erupciones volcánicas en el área, modificandotanto su abundancia como su composición, variando según la erupción y sus características.Más aún, en el Brazo Blest, se identificó la finalización de la PEH (aprox. 1400-1800 AD),con temperaturas bajas y altas precipitaciones, similar a lo encontrado en el Hemisferio Norte.En este sitio se observa un período con gran variabilidad de la temperatura y precipitaciones,hasta el año 1951 AD, a partir del que se nota un incremento en la temperatura dando lugar alas condiciones climáticas actuales presentes en la región.La utilización de proxies para realizar reconstrucciones en diversos sitios de la región esde gran utilidad para identificar variaciones climáticas históricas, y adquirir información sobrela dinámica y funcionamiento de los ecosistemas acuáticos. The main objective of this project was to study the response of chironomid assemblages (Insecta: Diptera: Chironomidae) to climatic and environmental changes, including those caused by natural disturbances (volcanism) that occurred in the North Patagonian region the last millennium. Two sites located in the western zone of the Nahuel Huapi National Park, and two sites located between the city of Esquel and Los Alerces National Park were studied to evaluate the possible differential response of the chironomid assemblages, through the analyses of the sedimentary records. In Laguna La Zeta a total of 17 morphotaxa were found (2098 chironomids), in Laguna Terraplén 18 morphotaxa were found (8006 chironomids), in the Laguna El Trébol 20 morfotaxas were found (4757 chironomids), and in Brazo Blest 27 morphotaxa were found (185 chironomids). The observed variations in the assemblages evidenced possible climatic changes and variations in the productivity of the system.In Laguna El Trébol the results suggested a wet and cold climate between 700 AD and 1300 AD, followed by a wet and warm climate until 1600 AD, from which changes to a dry and warm climate until the present, also evidenced in Brazo Blest. Moreover, in Brazo Blest, the end of the Little Ice Age (approx. 1400-1800 AD) was observed, with low temperatures and high precipitations. In La Zeta and Terraplén, there was an increase in productivity in the last 200 years. In general, the information provided by the sites studied provides an overview of what happened in the Andean range area of northern Patagonia. With the analysis of chironomids, climatic and productivity variations in the last 1000 years can be see, reason why bioproxies are an excellent tool for identifying historical environmental variations and acquiring information about the dynamics and functioning of aquatic ecosystems. With this knowledge one could understand the current conditions and infer future environmental scenarios. Fil: Serra, Maria Noel. Administración de Parques Nacionales. Delegación Regional Patagonia; Argentina
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- 2017
48. Polen
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Lozano García, María Socorro, Tonello, Marcela Sandra, Stutz, Silvina Maria, Pérez, Liseth, Massaferro, Julieta, and Correa Metrio, Alexander
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purl.org/becyt/ford/1 [https] ,CUATERNARIO ,purl.org/becyt/ford/1.5 [https] ,LATINOAMERICA ,PALEOLIMNOLOGIA ,PALEOECOLOGIA - Abstract
El estudio de los granos de polen y esporas o análisis palinológico, es un método ampliamente utilizado para reconstruir la historia de las comunidades de plantas terrestres y acuáticas y sus respuestas al cambio ambiental durante el Cuaternario (últimos 2 millones de años). Los granos de polen y las esporas se depositan en el fondo de los lagos, entre otros ambientes sedimentarios, y registran la variación en la composición de las comunidades vegetales pasadas y los cambios ambientales que han ocurrido. Sobre la Con base en del análisis de estos micro-restos en las secuencias lacustres se reconstruye la variabilidad climática del pasado. Los granos de polen de angiospermas y gimnospermas así como las esporas de helechos, musgos y hepáticas representan la flora terrestre y constituyen el tema de estudio de la Palinología, aunque en esta disciplina se analizan también restos algales provenientes generalmente de clorofíceas y cianobacterias, que forman parte del grupo de los palinomorfos no polínicos (PNPs). Entre las razones por las que se engloban estos restos de plantas en dicha disciplina, es que comparten ciertas características. Tienen en común el tamaño (5 a 500 micras), la composición química, así como los mecanismos de dispersión, a pesar de que los procesos reproductivos de estos grupos de plantas son distintos. Estos micro-restos se pueden dividir de acuerdo a su origen en endógenos, que provienen del lago y exógenos, que provienen de fuera del lago.La palinología es una disciplina que tiene más de 100 años, y durante este lapso numerosos trabajos y libros han sido publicados, enfocados tanto en cuestiones metodológicas como teóricas (Erdtman, 1952; Faegri e Iversen, 1989; Kapp, 1969; Seppä 2013; Traverse, 1988). En este capítulo se presentan generalidades del análisis polínico, (desde el origen del grano de polen a la reconstrucción de la vegetación en el pasado), con énfasis en la metodología relacionada con la obtención de muestras polínicas y su procesamiento para la extracción de palinomorfos. Se describen los antecedentes más importantes para Latinoamérica y el Caribe, y se presentan presentando ejemplos en los cuales el polen es utilizado en reconstrucciones paleoambientales y paleoclimáticas Fil: Lozano García, María Socorro. Universidad Nacional Autónoma de México; México Fil: Tonello, Marcela Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Stutz, Silvina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina
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- 2017
49. Mollusca
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Álvarez Sanhueza, Denisse, de Francesco, Claudio German, Pérez, Liseth, Massaferro, Julieta, and Correa Metrio, Alexander
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LAGOS SOMEROS ,CUATERNARIO ,MOLUSCOS ,PALEOECOLOGÍA ,Paleontología ,CIENCIAS NATURALES Y EXACTAS ,Ciencias de la Tierra y relacionadas con el Medio Ambiente - Abstract
Los moluscos (Phylum Mollusca) se encuentran entre los bioindicadores macroscópicosmás comúnmente hallados en los sedimentos continentales cuaternarios. Estánrepresentados exclusivamente por las clases Gastropoda (caracoles, babosas) yBivalvia (almejas, mejillones). La fauna dulceacuícola neotropical está representada poral menos 14 familias de gasterópodos, (Strong et al. 2008) y por aproximadamente 10familias de bivalvos (Bogan 2008). Habitan casi todo tipo de ambientes acuáticos comoríos, arroyos, canales, manantiales, cascadas, lagos, esteros y pantanos. La mayoría delas especies fósiles corresponden a especies que se encuentran en la actualidad, lo quepermite una aproximación uniformitarianista directa para inferir paleoambientes Fil: Álvarez Sanhueza, Denisse. Universidad Santo Tomás; Chile Fil: de Francesco, Claudio German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina
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- 2017
50. Fitolitos
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Zucol, Alejandro Fabián, Osterrieth, Margarita Luisa, Borrelli, Natalia Lorena, Patterer, Noelia Isabel, Pérez, Liseth, Massaferro, Julieta, and Correa Metrio, Alexander
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purl.org/becyt/ford/1 [https] ,purl.org/becyt/ford/1.5 [https] ,siliceos ,bioindicadores ,Fitolito ,calcicos - Abstract
Los fitolitos son biomineralizaciones de origen vegetal, es decir, depositaciones minerales ymineraloides generadas como consecuencia de distintos procesos metabólicos de losorganismos vegetales (Coe et al. 2014). Es relevante destacar que las biomineralizaciones hanacompañado la evolución de la vida desde los inicios de la presencia de la biota en el planeta;por lo cual están presentes en todos los niveles de la biósfera (Osterrieth 2004). En las plantasvasculares se encuentran presentes en idioblastos, elementos celulares discordantes del restode las células de los tejidos, denominados litocistes. Los fitolitos pueden formarse en elcitoplasma celular, ocupar todo el lumen de la célula o bien espacios intercelulares, dando origena distintas formas que en muchos casos permiten reconocer los tejidos en donde se originaron,como así también, el grupo taxonómico que los produce. De acuerdo a su composición química,los fitolitos pueden ser cálcicos o calcifitolitos, y se encuentran principalmente presentes endepositaciones cristalinas de oxalato y carbonato de calcio (Prychid & Rudall 1999), originadasmayoritariamente en los tejidos parenquimáticos. Por otra parte, los fitolitos silíceos o silicofitolitos, que se originan por la depositación de sílice amorfa hidratada o dióxido de siliciopolimerizado, principalmente en los tejidos epidérmicos/subepidérmico, de conducción y sostén(sensu Hayward & Parry 1973; Amos 1952). Fil: Zucol, Alejandro Fabián. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Osterrieth, Margarita Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Borrelli, Natalia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Patterer, Noelia Isabel. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina
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- 2017
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