Results 1 to 10 of about 196 (63)

Increased atmospheric CO2 and the transit time of carbon in terrestrial ecosystems

Global Change Biology, Volume 29, Issue 23, Page 6441-6452, December 2023., 2023
Terrestrial ecosystems remove CO2 from the atmosphere via photosynthesis and convert it into biomass and soil organic matter. This carbon is returned to the atmosphere via decomposition and respiration, processes that depend on climatic conditions, microbial community structure and function, and nutrient availability.
Estefanía Muñoz, Ingrid Chanca, Carlos A. Sierra   +2 more
wiley   +1 more source

Quantitative analysis of diurnal CO2 flux variations above an alkaline playa

Vadose Zone Journal, Volume 22, Issue 6, November/December 2023., 2023
Abstract The alkaline playas at Atlin, BC, provide a unique opportunity for studying the carbonate–bicarbonate system and carbonate mineral stability at the Earth's surface. In this study, dynamic closed chambers (DCCs) and pore‐gas sampling were used to directly quantify carbon dioxide (CO2) emission rates and characterize processes governing the CO2 ...
Anne‐Martine Doucet, Frances Jones, Katherine E. Raymond, Gregory Dipple, Thomas Andrew Black, Bethany Ladd, Klaus Ulrich Mayer   +6 more
wiley   +1 more source

Archaeology of animate ancestors and entanglement at Mayarnjarn in the Wellington Range region, Northern Territory

Archaeology in Oceania, Volume 58, Issue 2, Page 172-182, July 2023., 2023
ABSTRACT The Wellington Range region, in far Northern Australia, provides a remarkable record of cultural encounter. Cathedral‐sized rock art galleries include contact imagery referencing Macassan and European visitors while lithic artefact assemblages echo social mobility between Indigenous groups occurring from at least the mid Holocene period.
Duncan Wright, Ladislav Nejman, Steve Skitmore, Wayne Brennan, Rebecca Parkes, Ronald Lamilami, Paul S. C. Taçon   +6 more
wiley   +1 more source

Relationships between carbon age and CO2 efflux in agricultural and drainage ditch soils using the thermonuclear bomb pulse

Vadose Zone Journal, Volume 21, Issue 5, September/October 2022., 2022
Abstract Agricultural soils contribute significantly to global CO2 emissions. Soils can be both a CO2 sink and source depending on vegetation cover and the physical‐chemical characteristics of the soil environment. This study uses a new 14C dating approach to elucidate soil physical and geochemical properties that drive the production and transport of ...
Oliver Blume, Eric Guitard, Carley Crann, Michel Orekhov, Richard Amos, Ian Clark, David Lapen, David Blowes, Carol Ptacek, Emilia Craiovan, Mark Sunohara   +10 more
wiley   +1 more source

Aplicação do isótopo radioativo de carbono (14c) na determinação de tempos de residência em aquíferos

Derbyana, 2021
O uso de isótopos em estudos hidrogeológicos constitui uma importante ferramenta na construção de modelos conceituais de funcionamento, bem como na determinação de parâmetros relacionados à recarga e ao fluxo das águas subterrâneas.
Gerson Cardoso da Silva Jr., Renato Cosme dos Santos Pita, Fernanda Caetano de Mattos Bastos Cunha, Talita Azevedo da Silva   +3 more
doaj   +1 more source

MicroCT scanning and direct AMS dating of charred sweet potato (Ipomoea batatas) fragments from Nombe rockshelter in the highlands of Papua New Guinea

Archaeology in Oceania, Volume 57, Issue 2, Page 146-149, July 2022., 2022
Abstract Here, we report on the results of microCT scanning and Accelerator Mass Spectrometry (AMS) radiocarbon dating of fragments of charred archaeological parenchyma collected from surface deposits at Nombe rockshelter in the highlands of Papua New Guinea. Five fragments are taxonomically identified as sweet potato (Ipomoea batatas).
ALEESE BARRON, MARY‐JANE MOUNTAIN, TIM DENHAM   +2 more
wiley   +1 more source

Sobre la cronología del inicio de la imposición cuzqueña en Chile

Estudios Atacameños, 2014
Se discute la cronología en que el norte y centro de Chile fue incorporado al Tawantinsuyu. Partiendo de la ya generalizada opinión acerca de que la fecha de 1470 DC para la incorporación de estos territorios, propuesta a partir de los estudios clásicos
Luis Eduardo Cornejo Bustamante
doaj   +8 more sources

Probability Distributions of Radiocarbon in Open Linear Compartmental Systems at Steady‐State

Journal of Geophysical Research: Biogeosciences, Volume 127, Issue 3, March 2022., 2022
Abstract Radiocarbon (14C) is commonly used as a tracer of the carbon cycle to determine how fast carbon moves between different reservoirs such as plants, soils, rivers, or oceans. However such studies mostly emphasize the mean value (as Δ14C) of an unknown probability distribution.
Ingrid Chanca, Susan Trumbore, Kita Macario, Carlos A. Sierra   +3 more
wiley   +1 more source

Secuencias cronológicas del Calcolítico y Edad del Bronce en el interior de la Península Ibérica: Análisis de las dataciones de Las Mayores (Numancia de la Sagra, Toledo) en su entorno regional [PDF]

Munibe Antropologia-Arkeologia, 2021
Analizamos los datos cronológicos del registro funerario del yacimiento de Las Mayores, Toledo, un poblado de estructuras subterráneas que incluyen enterramientos.
Rosa Barroso Bermejo, Enrique Cerrillo Cuenca, Primitiva Bueno Ramírez, Armando González Martín   +3 more
doaj   +1 more source

Radiocarbono y arqueología

Educación Química, 2018
La arqueología es una disciplina antropológica que estudia el pasado del hombre a través de la recuperación, análisis e interpretación de los restos materiales de las culturas (Mignon, 1993). Los arqueólogos tratan de reconstruir el proceso que ha creado
Luz Lazos Ramírez
doaj   +1 more source