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Van Devender, Thomas R. - One of the best experts on this subject based on the ideXlab platform.
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Retrospectiva del bosque de pino y encino de la Sierra Madre Occidental, Sonora, Noroeste de México, hace 1000 años
'Instituto de Ecologia A.C.', 2008Co-Authors: Ortega-rosas, Carmen Isela, Peñalba M. Cristina, López-sáez, José Antonio, Van Devender, Thomas R.Abstract:The Ciénega de Camilo is a Sphagnum palustre seep in a canyon in dense pine-oak forest with four species of pine and seven of oak in the Sierra Madre Occidental of eastern Sonora, Mexico. Analyses of pollen and non-pollen palynomorphs in two sediment cores show that pine-oak forest has been at the site during the last thousand years. When sedimentation began about 1000 years ago (1058 ±60 and 870 ±70 cal. BP (calibrated years before present)), pine was more abundant than today with an additional species with large pollen grains now present at higher elevation. The abundance and diversity of ferns were higher. Non-pollen palynomorphs suggest moister (presence of Copepoda), and eu- to mesotrophic conditions at the base, followed by drier conditions (unidentified amerospores, type 55A, Zygnemataceae, and Pediastrum), leading to the most recent mesotrophic-Ombrotrophic Environment characterized by Pleospora, type 82E, and the Sphagnum palustre seep. The inferred wet period at around 1000 cal.BP followed by drier and warmer climates is contemporaneous with the maximum development of the Sonoran and Chihuahuan desert archeological cultures.La Ciénega de Camilo es un humedal con Sphagnum palustre localizado en un bosque denso de pino y encino con cuatro especies de Pinus y siete de Quercus, en la Sierra Madre Occidental, en la región este de Sonora. Los análisis de polen y palinomorfos no polínicos de dos núcleos de sedimento muestran que el bosque de pino y encino ha existido en el lugar durante el último milenio. Sin embargo, hace alrededor de mil años (1058 ±60 y 870 ±70 años cal. BP (años calibrados antes del presente)), el pino era más abundante que hoy día, y además crecía una especie de pino adicional, posiblemente del grupo de Pinus strobiformis, que hoy prospera a mayores elevaciones, en un clima más fresco y húmedo. Había abundancia y diversidad de helechos. Los palinomorfos no polínicos sugieren condiciones más húmedas (presencia de Copepoda) y eu- a mesotróficas en la base, seguidas por condiciones más secas (amerosporas indiferenciadas, tipo 55A, Zygnemataceae y Pediastrum), conducentes al medio ambiente mesotrófico-ombrotrófico más reciente caracterizado por Pleospora y tipo 82E, que refleja la ciénega de Sphagnum palustre. Se infiere que hubo un período húmedo hace alrededor de 1000 años (14C BP), contemporáneo con el máximo desarrollo de las culturas arqueológicas de los desiertos Sonorense y Chihuahuense, que fue seguido por un clima progresivamente más seco y cálido
Ortega-rosas, Carmen Isela - One of the best experts on this subject based on the ideXlab platform.
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Retrospectiva del bosque de pino y encino de la Sierra Madre Occidental, Sonora, Noroeste de México, hace 1000 años
'Instituto de Ecologia A.C.', 2008Co-Authors: Ortega-rosas, Carmen Isela, Peñalba M. Cristina, López-sáez, José Antonio, Van Devender, Thomas R.Abstract:The Ciénega de Camilo is a Sphagnum palustre seep in a canyon in dense pine-oak forest with four species of pine and seven of oak in the Sierra Madre Occidental of eastern Sonora, Mexico. Analyses of pollen and non-pollen palynomorphs in two sediment cores show that pine-oak forest has been at the site during the last thousand years. When sedimentation began about 1000 years ago (1058 ±60 and 870 ±70 cal. BP (calibrated years before present)), pine was more abundant than today with an additional species with large pollen grains now present at higher elevation. The abundance and diversity of ferns were higher. Non-pollen palynomorphs suggest moister (presence of Copepoda), and eu- to mesotrophic conditions at the base, followed by drier conditions (unidentified amerospores, type 55A, Zygnemataceae, and Pediastrum), leading to the most recent mesotrophic-Ombrotrophic Environment characterized by Pleospora, type 82E, and the Sphagnum palustre seep. The inferred wet period at around 1000 cal.BP followed by drier and warmer climates is contemporaneous with the maximum development of the Sonoran and Chihuahuan desert archeological cultures.La Ciénega de Camilo es un humedal con Sphagnum palustre localizado en un bosque denso de pino y encino con cuatro especies de Pinus y siete de Quercus, en la Sierra Madre Occidental, en la región este de Sonora. Los análisis de polen y palinomorfos no polínicos de dos núcleos de sedimento muestran que el bosque de pino y encino ha existido en el lugar durante el último milenio. Sin embargo, hace alrededor de mil años (1058 ±60 y 870 ±70 años cal. BP (años calibrados antes del presente)), el pino era más abundante que hoy día, y además crecía una especie de pino adicional, posiblemente del grupo de Pinus strobiformis, que hoy prospera a mayores elevaciones, en un clima más fresco y húmedo. Había abundancia y diversidad de helechos. Los palinomorfos no polínicos sugieren condiciones más húmedas (presencia de Copepoda) y eu- a mesotróficas en la base, seguidas por condiciones más secas (amerosporas indiferenciadas, tipo 55A, Zygnemataceae y Pediastrum), conducentes al medio ambiente mesotrófico-ombrotrófico más reciente caracterizado por Pleospora y tipo 82E, que refleja la ciénega de Sphagnum palustre. Se infiere que hubo un período húmedo hace alrededor de 1000 años (14C BP), contemporáneo con el máximo desarrollo de las culturas arqueológicas de los desiertos Sonorense y Chihuahuense, que fue seguido por un clima progresivamente más seco y cálido
Michael Wagreich - One of the best experts on this subject based on the ideXlab platform.
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Anthropogenic and climate signals in late-Holocene peat layers of an Ombrotrophic bog in the Styrian Enns valley (Austrian Alps)
E&G Quaternary Science Journal, 2020Co-Authors: Wolfgang Knierzinger, Ruth Drescher-schneider, Klaus-holger Knorr, Simon Drollinger, Andreas Limbeck, Lukas Brunnbauer, Felix Horak, Daniela Festi, Michael WagreichAbstract:Abstract. Using peat bogs as palaeoEnvironmental archives is a well-established practice for reconstructing changing climate and anthropogenic activity in the past. In this paper, we present multi-proxy analyses (element geochemistry, pollen, non-pollen palynomorphs, stable Pb isotopes, humification, ash content) of a 500 cm long, 14 C-dated peat core covering the past ∼5000 years from the Ombrotrophic Purgschachen Moor in the Styrian Enns valley (Austrian Alps). Early indications of low settlement and agricultural activity date to ∼2900 cal BCE. An early enrichment of Cu was found in peat layers corresponding to the late Copper Age ( ∼2500 cal BCE). These enrichments are attributed to Cu mining activities in the Eisenerz Alps. More pronounced increases in cultural indicators (cultivated plants, shrubs, herbs, charcoal) in the pollen record and enrichments of trace metals suggest significant human impact in the vicinity of Purgschachen Moor in the middle Bronze Age ( ∼1450 –1250 cal BCE), in the late Bronze Age ( ∼1050 –800 cal BCE) and in the period of the late La Tene culture ( ∼300 cal BCE–1 cal CE). The greater part of the Iron Age and the Roman imperial period are each characterized by a general decline in anthropogenic indicators compared to previous periods. Distinct enrichments of Pb and Sb in the sample that corresponds to ∼900 cal CE are attributed to medieval siderite mining activity in the immediate vicinity of Purgschachen Moor. The results of this interdisciplinary study provide evidence that strong, climate-controlled interrelations exist between the pollen record, the humification degree and the ash content in an Ombrotrophic Environment. Human activity, in contrast, is mainly reflected in the pollen record and by enrichments of heavy metals. The study indicates a dry period in the region of the bog around ∼1950 cal BCE.
Malin Bomberg - One of the best experts on this subject based on the ideXlab platform.
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Microbial Community Composition Correlates with Metal Sorption in an Ombrotrophic Boreal Bog: Implications for Radionuclide Retention
Soil Systems, 2021Co-Authors: Merja Lusa, Malin BombergAbstract:Microbial communities throughout the 6.5 m depth profile of a boreal Ombrotrophic bog were characterized using amplicon sequencing of archaeal, fungal, and bacterial marker genes. Microbial populations and their relationship to oxic and anoxic batch sorption of radionuclides (using radioactive tracers of I, Se, Cs, Ni, and Ag) and the prevailing metal concentrations in the natural bog was investigated. The majority of the detected archaea belonged to the Crenarchaeota, Halobacterota, and Thermoplasmatota, whereas the fungal communities consisted of Ascomycota, Basidiomycota, and unclassified fungi. The bacterial communities consisted mostly of Acidobacteriota, Proteobacteria, and Chloroflexi. The occurrence of several microbial genera were found to statistically significantly correlate with metal concentrations as well as with Se, Cs, I, and Ag batch sorption data. We suggest that the metal concentrations of peat, gyttja, and clay layers affect the composition of the microbial populations in these nutrient-low conditions and that particularly parts of the bacterial and archaeal communities tolerate high concentrations of potentially toxic metals and may concurrently contribute to the total retention of metals and radionuclides in this Ombrotrophic Environment. In addition, the varying metal concentrations together with chemical, mineralogical, and physical factors may contribute to the shape of the total archaeal and bacterial populations and most probably shifts the populations for more metal resistant genera.
López-sáez, José Antonio - One of the best experts on this subject based on the ideXlab platform.
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Retrospectiva del bosque de pino y encino de la Sierra Madre Occidental, Sonora, Noroeste de México, hace 1000 años
'Instituto de Ecologia A.C.', 2008Co-Authors: Ortega-rosas, Carmen Isela, Peñalba M. Cristina, López-sáez, José Antonio, Van Devender, Thomas R.Abstract:The Ciénega de Camilo is a Sphagnum palustre seep in a canyon in dense pine-oak forest with four species of pine and seven of oak in the Sierra Madre Occidental of eastern Sonora, Mexico. Analyses of pollen and non-pollen palynomorphs in two sediment cores show that pine-oak forest has been at the site during the last thousand years. When sedimentation began about 1000 years ago (1058 ±60 and 870 ±70 cal. BP (calibrated years before present)), pine was more abundant than today with an additional species with large pollen grains now present at higher elevation. The abundance and diversity of ferns were higher. Non-pollen palynomorphs suggest moister (presence of Copepoda), and eu- to mesotrophic conditions at the base, followed by drier conditions (unidentified amerospores, type 55A, Zygnemataceae, and Pediastrum), leading to the most recent mesotrophic-Ombrotrophic Environment characterized by Pleospora, type 82E, and the Sphagnum palustre seep. The inferred wet period at around 1000 cal.BP followed by drier and warmer climates is contemporaneous with the maximum development of the Sonoran and Chihuahuan desert archeological cultures.La Ciénega de Camilo es un humedal con Sphagnum palustre localizado en un bosque denso de pino y encino con cuatro especies de Pinus y siete de Quercus, en la Sierra Madre Occidental, en la región este de Sonora. Los análisis de polen y palinomorfos no polínicos de dos núcleos de sedimento muestran que el bosque de pino y encino ha existido en el lugar durante el último milenio. Sin embargo, hace alrededor de mil años (1058 ±60 y 870 ±70 años cal. BP (años calibrados antes del presente)), el pino era más abundante que hoy día, y además crecía una especie de pino adicional, posiblemente del grupo de Pinus strobiformis, que hoy prospera a mayores elevaciones, en un clima más fresco y húmedo. Había abundancia y diversidad de helechos. Los palinomorfos no polínicos sugieren condiciones más húmedas (presencia de Copepoda) y eu- a mesotróficas en la base, seguidas por condiciones más secas (amerosporas indiferenciadas, tipo 55A, Zygnemataceae y Pediastrum), conducentes al medio ambiente mesotrófico-ombrotrófico más reciente caracterizado por Pleospora y tipo 82E, que refleja la ciénega de Sphagnum palustre. Se infiere que hubo un período húmedo hace alrededor de 1000 años (14C BP), contemporáneo con el máximo desarrollo de las culturas arqueológicas de los desiertos Sonorense y Chihuahuense, que fue seguido por un clima progresivamente más seco y cálido
