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The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations
Published on: August 3, 2016
Evidencia de una desnitrificación completa en un foraminifero bentónico
Nils Risgaard-Petersen1, Alexandra M Langezaal, Signe Ingvardsen
1Department of Marine Ecology, National Environmental Research Institute, Vejlsøvej 25, DK-8600 Silkeborg, Denmark. nri@dmu.dk
Nature
|September 8, 2006
Resumen
Los benthic foraminifera almacenan y respiran nitrato intracelular, lo que permite la supervivencia en entornos marinos anóxicos. Este hallazgo revela un metabolismo anaeróbico no descrito previamente crucial para el ciclo del nitrógeno.
Área de la Ciencia:
- Biología Marina Biología Marina.
- La geoquímica es la geoquímica.
- Microbiología Microbiología.
Sus antecedentes:
- Los foraminíferos bentónicos son abundantes eucariotas unicelulares en los sedimentos marinos.
- Muchas especies habitan en ambientes anóxicos, pero el metabolismo anaeróbico sostenible no se entendía bien.
Objetivo del estudio:
- Para investigar el metabolismo anaeróbico de las foraminíferas bentónicas.
- Para determinar si los foraminiferos pueden utilizar el nitrato almacenado para la respiración en hábitats libres de oxígeno.
Principales métodos:
- Cuantificación de las reservas intracelulares de nitrato en los foraminiferos.
- Experimentos de respiración para confirmar la utilización de nitratos.
- Muestreo de campo en el fiordo sueco y en los sedimentos de la plataforma continental chilena.
Principales resultados:
- Se demostró que Globobulimina pseudospinescens se acumula y respira nitrato intracelular a gas dinitrógeno.
- Se estima que las reservas de nitrato son suficientes para más de un mes de respiración.
- Se detectaron altas concentraciones intracelulares de nitrato en múltiples especies dominantes de foraminíferos bentónicos.
Conclusiones:
- Los foraminiferos poseen una vía metabólica anaeróbica sostenible que utiliza nitrato intracelular.
- Es probable que las foraminíferas desempeñen un papel importante en el ciclo del nitrógeno marino.
- La comprensión actual del ciclo del nitrógeno marino requiere un mayor refinamiento para incluir las contribuciones foraminiferales.
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