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Assessment of Labile Organic Carbon in Soil Using Sequential Fumigation Incubation Procedures
Published on: October 29, 2016
Bromuro de metilo atmosférico (CH3Br) de las fumigaciones del suelo agrícola
Science (New York, N.Y.)
|March 31, 1995
Resumen
La fumigación del suelo con bromuro de metilo (MeBr) libera MeBr atmosférico significativo, lo que contribuye al agotamiento del ozono. La optimización de las condiciones del suelo y los métodos de inyección pueden reducir las emisiones de MeBr de las aplicaciones agrícolas.
Área de la Ciencia:
- Química del medio ambiente Química del medio ambiente
- Ciencias de la atmósfera Ciencias atmosféricas.
- Ciencias del suelo Ciencias del suelo.
Sus antecedentes:
- La fumigación del suelo con bromuro de metilo (MeBr) es una fuente potencialmente significativa de MeBr atmosférico.
- El MeBr atmosférico está implicado en el agotamiento del ozono estratosférico.
- Comprender el destino ambiental del MeBr es crucial para mitigar el daño de la capa de ozono.
Objetivo del estudio:
- Para cuantificar la liberación atmosférica de MeBr por fumigación de suelos agrícolas.
- Para evaluar el destino del MeBr en el suelo, específicamente el aumento del bromuro.
- Identificar los factores que influyen en el escape atmosférico del MeBr.
Principales métodos:
- Realizó un experimento de fumigación de campo utilizando MeBr.
- Flujo atmosférico de MeBr medido durante 7 días.
- Análisis de las concentraciones de bromuro en el suelo después de la fumigación.
- Se compararon los resultados con un experimento anterior con mayor escape atmosférico de MeBr.
Principales resultados:
- El 34% del MeBr aplicado escapó a la atmósfera en un plazo de 7 días.
- El bromuro del suelo aumentó en un 70% del MeBr aplicado, consistente con los datos de flujo (dentro del 4%).
- El pH más alto del suelo, el contenido orgánico, la humedad y la inyección más profunda/uniforme se correlacionaron con un escape reducido de MeBr.
Conclusiones:
- La fumigación del suelo de MeBr conduce a emisiones atmosféricas sustanciales.
- El aumento del bromuro en el suelo confirma la transformación y retención de MeBr.
- La optimización de las propiedades del suelo y las técnicas de inyección pueden minimizar la liberación atmosférica de MeBr.
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