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Updated: Jul 6, 2026
12:59
A Study of the Complexation of Mercury(II) with Dicysteinyl Tetrapeptides by Electrospray Ionization Mass Spectrometry
Published on: January 8, 2016
El aumento de las tasas de deposición atmosférica de mercurio en el centro continental de América del Norte
Science (New York, N.Y.)
|August 7, 1992
Resumen
La deposición de mercurio atmosférico en lagos remotos se ha triplicado desde 1850, con el 25% del mercurio de la atmósfera exportado de la tierra circundante al lago. Esto sugiere fuentes de mercurio extendidas.
Área de la Ciencia:
- Ciencias ambientales Ciencias ambientales.
- La geoquímica es la geoquímica.
- Ecología Ecología Ecología.
Sus antecedentes:
- La contaminación por mercurio en lagos remotos es una preocupación creciente.
- Las tasas históricas de deposición de mercurio y los insumos terrestres son poco conocidos.
- La deposición atmosférica de mercurio es la principal fuente sospechosa.
Objetivo del estudio:
- Para reconstruir las tasas de deposición de mercurio en lagos remotos.
- Para cuantificar la exportación terrestre de mercurio atmosférico a los lagos.
- Para identificar las fuentes de contaminación por mercurio.
Principales métodos:
- Análisis de sedimentos lacustres de siete lagos de cabecera en Minnesota y Wisconsin.
- La datación de núcleos de sedimentos para establecer líneas de tiempo históricas.
- Cálculo de flujos de mercurio de toda la cuenca.
Principales resultados:
- La deposición anual de mercurio en la atmósfera aumentó de 3.7 a 12.5 μg/m2 desde 1850.
- El 25% del depósito de mercurio atmosférico en la cuenca se exporta al lago.
- Aumentos de deposición similares en todos los sitios sugieren fuentes regionales o globales.
Conclusiones:
- La deposición de mercurio en lagos remotos ha aumentado significativamente desde la era preindustrial.
- Los ecosistemas terrestres actúan como una vía significativa para que el mercurio entre en los lagos.
- Es probable que los procesos atmosféricos regionales o globales estén impulsando la contaminación por mercurio en estos lagos remotos.
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