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Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds
Published on: September 26, 2017
Una disminución en el transporte de plomo por el río Mississippi
Resumen
El plomo contaminante que ingresa al Golfo de México a través del río Mississippi ha disminuido en un 40% en diez años. Esta disminución está vinculada a la reducción del uso de gasolina con plomo en los Estados Unidos e impacta en la deposición de sedimentos fluviales.
Área de la Ciencia:
- Ciencias ambientales Ciencias ambientales.
- La geoquímica es la geoquímica.
- Hidrología Hidrología Hidrología.
Sus antecedentes:
- El plomo contaminante del río Mississippi representa un riesgo para el ecosistema del Golfo de México.
- Comprender el transporte y la deposición de plomo es crucial para la gestión ambiental.
Objetivo del estudio:
- Para cuantificar la tendencia reciente en las entradas de plomo contaminante al Golfo de México desde el río Mississippi.
- Identificar los principales factores que contribuyen a los cambios observados en las cargas de plomo.
Principales métodos:
- Análisis de las cargas anuales de plomo en el río Mississippi.
- Examen de los registros de concentración de plomo en los sedimentos del Delta del Mississippi.
Principales resultados:
- Una disminución significativa de aproximadamente el 40% en las entradas de plomo fluvial en la última década.
- El consumo de plomo en la gasolina de Estados Unidos se identificó como un factor contribuyente importante.
- Más del 90% del plomo de los ríos es de partículas, depositándose principalmente cerca de la desembocadura del río.
Conclusiones:
- La reducción del consumo de gasolina con plomo ha llevado a una disminución de la contaminación por plomo en el Golfo de México.
- El plomo unido a las partículas muestra una movilidad limitada en los sedimentos del delta bajo condiciones ambientales típicas.
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