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Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA)
Published on: May 16, 2016
Morfologías y origen del carbono elemental en el medio ambiente
Science (New York, N.Y.)
|November 2, 1979
Resumen
Un reciente análisis de partículas de carbono revela que los sedimentos del lago Michigan después de 1900 contienen carbono de carbón, petróleo y madera. Las capas más antiguas del lecho del lago muestran exclusivamente carbono derivado de la madera, lo que indica un cambio significativo en las fuentes de contaminación a lo largo del tiempo.
Área de la Ciencia:
- Ciencias ambientales Ciencias ambientales.
- La geoquímica es la geoquímica.
- La paleolimnología.
Sus antecedentes:
- Los sedimentos del lago Michigan actúan como archivos de las condiciones ambientales pasadas.
- Comprender las fuentes históricas de carbono es crucial para evaluar los impactos de la contaminación.
Objetivo del estudio:
- Para identificar y comparar fuentes de partículas de carbono en los sedimentos del lago Michigan.
- Para establecer una línea de tiempo para la introducción de diferentes tipos de carbono en el lago.
Principales métodos:
- La recolección de sedimentos de núcleo utilizando la técnica de caja de núcleo.
- Extracción y análisis de partículas de carbono de muestras de sedimentos.
- Comparación de las partículas extraídas con fuentes conocidas como petróleo, carbón y ceniza volante de madera.
Principales resultados:
- Los sedimentos depositados después de 1900 contienen partículas de carbono originadas del carbón, el petróleo y la madera.
- Los sedimentos más antiguos de 1900 contienen exclusivamente partículas de carbono derivadas de la madera.
- Esto indica un cambio en las entradas antropogénicas de carbono al lago Michigan.
Conclusiones:
- La composición de las partículas de carbono en los sedimentos del lago Michigan proporciona un claro registro histórico de la contaminación.
- El aumento posterior a 1900 en el carbono del carbón y el petróleo refleja la industrialización y el uso de combustibles fósiles.
- El carbono de madera sigue siendo un componente consistente, aunque no exclusivo, en todo el registro de sedimentos analizado.
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