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Patrones y mecanismos recientes de intercambio de carbono por los ecosistemas terrestres
D S Schimel1, J I House, K A Hibbard
1Max Planck Institute für Biogeochemie, Jena, Germany. schmiel@ucar.edu
Nature
|November 9, 2001
Resumen
Los ecosistemas terrestres se convirtieron en un importante sumidero de carbono en la década de 1990, absorbiendo dióxido de carbono atmosférico. Este cambio, principalmente en las regiones del norte, ayuda a limitar el cambio climático, pero implica incertidumbres en su estabilidad y procesos a largo plazo.
Área de la Ciencia:
- Ciencias del Sistema Terrestre Ciencias del Sistema Terrestre
- Ecología Ecología Ecología.
- Ciencias del clima Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- Los ecosistemas terrestres y marinos absorben aproximadamente el 50% de las emisiones antropogénicas de dióxido de carbono.
- Comprender el intercambio de carbono es crucial para predecir los cambios atmosféricos y climáticos.
- La estabilidad a largo plazo de esta absorción de carbono sigue siendo incierta.
Objetivo del estudio:
- Proporcionar una visión general de los patrones globales y regionales de intercambio de carbono en los ecosistemas terrestres.
- Analizar la evolución del sumidero de carbono terrestre desde la década de 1980 hasta la de 1990.
- Identificar los factores que contribuyen a los cambios en el intercambio de carbono terrestre.
Principales métodos:
- Análisis de datos atmosféricos de dióxido de carbono y oxígeno.
- Evaluación de los patrones globales y regionales de intercambio de carbono.
- Revisión de los cambios en el uso de la tierra y los factores ambientales que influyen en el ciclo del carbono.
Principales resultados:
- La biosfera terrestre pasó de un intercambio de carbono casi neutral en la década de 1980 a un sumidero neto de carbono en la década de 1990.
- Las áreas extratropicas del norte, particularmente América del Norte y Eurasia, contribuyeron en gran medida a este reciente hundimiento.
- Las áreas terrestres tropicales mostraron un intercambio de carbono casi neutral, equilibrando las emisiones de la deforestación.
Conclusiones:
- Los ecosistemas terrestres juegan un papel vital en la mitigación del cambio climático mediante la absorción de dióxido de carbono atmosférico.
- Los cambios en el uso de la tierra y los factores ambientales, como temporadas de crecimiento más largas y fertilización de CO2, impulsan el sumidero de carbono terrestre.
- Persisten importantes incertidumbres con respecto a la magnitud del sumidero en todas las regiones y las contribuciones específicas de varios procesos.
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