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Hierro soluble y coloidal en el oligotrófico Atlántico Norte y Pacífico Norte
1Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. jingfeng@mit.edu
Science (New York, N.Y.)
|August 4, 2001
Resumen
La ultrafiltración revela una menor cantidad de hierro soluble y ligandos en los océanos de lo que se pensaba anteriormente. Gran parte de este hierro es coloidal, lo que afecta la biodisponibilidad del fitoplancton y los modelos oceánicos del ciclo del hierro.
Área de la Ciencia:
- Química marina La química marina es la química de los océanos.
- Oceanografía La oceanografía es la oceanografía.
- Biogeoquímica La biogeoquímica es la bioquímica.
Sus antecedentes:
- Las estimaciones anteriores de las estimaciones anteriores de las estimaciones anteriores.
Objetivo del estudio:
- Investigar las verdaderas concentraciones y especiación del hierro en los océanos oligotróficos.
- Aclarar la biodisponibilidad del hierro para el fitoplancton.
- Mejorar los modelos oceánicos del ciclo del hierro.
Principales métodos:
- Técnicas de ultrafiltración para separar las fracciones solubles y coloidales.
- Análisis de las concentraciones de hierro y de ligandos orgánicos que se unen al hierro.
- Comparación de las distribuciones de hierro por tamaño fraccionado con los perfiles de nutrientes.
Principales resultados:
- El hierro soluble y los ligandos son significativamente más bajos que los definidos anteriormente.
Conclusiones:
- Una parte sustancial del hierro oceánico existe en el rango de tamaño coloidal.
- La dinámica del hierro coloidal, incluyendo la agregación y el asentamiento, es crítica para el ciclo oceánico del hierro.
- Es necesaria una reevaluación de la biodisponibilidad del hierro para el fitoplancton basándose en nuevos datos de fraccionamiento de tamaño.
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