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Updated: Jul 12, 2026
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Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.
Published on: June 4, 2021
El equilibrio de sílice en el océano mundial: una reevaluación
Science (New York, N.Y.)
|April 21, 1995
Resumen
Las entradas de sílice del océano global de los ríos se revisan a 6.1 teramoles por año, equilibrando las salidas de los sedimentos marinos. Esta investigación refina la comprensión del ciclo del silicio marino.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Oceanografía La oceanografía es la oceanografía.
- Ciclos biogeoquímicos y ciclos biogeoquímicos.
Sus antecedentes:
- El ciclo global del silicio es crucial para los ecosistemas marinos y los procesos geológicos.
- Las estimaciones anteriores de los aportes de ácido silícico al océano carecían de precisión.
Objetivo del estudio:
- Para revisar y cuantificar las entradas netas de ácido silícico en el océano mundial.
- Para equilibrar estas entradas con las salidas de sílice biogénica en los sedimentos marinos.
- Para estimar la producción bruta de sílice biogénica y las tasas de preservación.
Principales métodos:
- Compilación y análisis de las concentraciones de ácido silícico fluvial.
- Cuantificación del enterramiento biogénico de sílice en sedimentos marinos.
- Estimación de la producción de sílice biogénica en aguas superficiales.
Principales resultados:
- La entrada neta revisada de ácido silícico en el océano es de 6,1 ± 2,0 teramoles de silicio por año, principalmente de los ríos (concentración media de 150 μM).
- Las salidas netas de sílice biogénica a los sedimentos son de 7.1 ± 1.8 teramoles de silicio por año, equilibrando las entradas.
- La producción bruta de sílice biogénica es de 240 ± 40 teramoles de silicio por año, con una relación de conservación del 3%.
Conclusiones:
- Las entradas y salidas de silicio oceánico están en equilibrio aproximado.
- El tiempo de residencia del silicio en el océano es de aproximadamente 400 años en relación con la absorción biológica.
- Este estudio proporciona cifras actualizadas para los parámetros clave del ciclo del silicio marino.
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