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Assessment of Labile Organic Carbon in Soil Using Sequential Fumigation Incubation Procedures
Published on: October 29, 2016
Hay evidencia de solo pequeñas contribuciones de las bacterias al carbono orgánico sedimentario
W A Hartgers1, J S Sinninghe Damste, A G Requejo
1Division of Marine Biogeochemistry, Netherlands Institute for Sea Research, Texel.
Nature
|May 19, 1994
Resumen
A pesar de los biomarcadores bacterianos prominentes en las rocas fuentes de petróleo, el análisis isotópico revela una mínima contribución bacteriana al carbono orgánico total (Corg). Esto sugiere que las bacterias son a menudo componentes menores en las rocas carbonáceas.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- La geoquímica orgánica es la geoquímica orgánica.
- Ecología microbiana ecología microbiana.
Sus antecedentes:
- Las bacterias a menudo se consideran los principales contribuyentes a los lechos de fuentes de petróleo debido a las firmas moleculares prominentes en los sedimentos.
- Sin embargo, las abundancias de biomarcadores pueden no reflejar con precisión las contribuciones reales al carbono orgánico sedimentario (Corg).
- La contribución de las bacterias fotosintéticas de azufre verde se puede evaluar a través de productos diagenéticos de sus carotenoides y enriquecimiento con 13C en su biomasa.
Objetivo del estudio:
- Investigar la contribución real de las bacterias al carbono orgánico sedimentario (Corg) en las rocas fuentes de petróleo.
- Para conciliar la discrepancia entre los biomarcadores bacterianos prominentes y la evidencia isotópica.
Principales métodos:
- Análisis de las firmas moleculares (biomarcadores) en sedimentos y aceites.
- Análisis isotópico (13C enriquecimiento) del carbono orgánico total (Corg).
Principales resultados:
- Los sedimentos y aceites de las cuencas del oeste de Canadá y Williston mostraron biomarcadores prominentes de bacterias fotosintéticas.
- La ausencia de enriquecimiento con 13C en el total de Corg indicó una contribución bacteriana mínima.
- La reelaboración bacteriana de los desechos sedimentarios es importante, pero la biomasa bacteriana es probablemente un componente menor del total de Corg.
Conclusiones:
- Los biomarcadores bacterianos prominentes no necesariamente equivalen a una contribución significativa al carbono orgánico total (Corg) en las rocas fuente de petróleo.
- La biomasa bacteriana comúnmente representa una fracción menor del total de Corg en las rocas carbonáceas.
- El análisis isotópico es crucial para evaluar con precisión las contribuciones bacterianas a la materia orgánica sedimentaria.
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