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Tendencias de la calidad del agua en los ríos de la nación
Science (New York, N.Y.)
|March 27, 1987
Resumen
El análisis a largo plazo de la calidad del agua de los ríos de Estados Unidos revela cambios significativos entre 1974-1981. Los hallazgos clave incluyen una disminución de las bacterias fecales y el plomo, junto con un aumento de los niveles de nitrato, cloruro, arsénico y cadmio.
Área de la Ciencia:
- Ciencias del medio ambiente Ciencias del medio ambiente.
- Monitoreo de la calidad del agua Monitoreo de la calidad del agua
- Sistemas Fluviales de los Estados Unidos.
Sus antecedentes:
- Los principales cambios en las influencias terrestres y atmosféricas ocurrieron entre 1974-1981.
- Comprender las tendencias a largo plazo de la calidad del agua es crucial para la gestión ambiental.
- Los datos nacionales de calidad del agua proporcionan una visión integral de la salud del río.
Objetivo del estudio:
- Para analizar las tendencias a largo plazo de la calidad del agua en los principales ríos de Estados Unidos.
- Para correlacionar los cambios observados en la calidad del agua con factores ambientales e industriales.
- Proporcionar información sobre la dinámica de la calidad del flujo durante un período de cambios ambientales significativos.
Principales métodos:
- Se utilizaron registros de calidad del agua de dos redes nacionales de muestreo.
- Analizó las tendencias en 24 parámetros de calidad del agua.
- Centrado en datos de más de 300 ubicaciones en los principales ríos de los Estados Unidos de 1974 a 1981.
Principales resultados:
- Se observaron disminuciones generalizadas en las bacterias fecales y las concentraciones de plomo.
- Se han documentado aumentos generalizados en las concentraciones de nitrato, cloruro, arsénico y cadmio.
- Se identificaron correlaciones entre los cambios en la calidad del agua y factores como el tratamiento de residuos, el uso de sal en las carreteras, la aplicación de fertilizantes y el consumo de gasolina.
Conclusiones:
- Los cambios en la calidad del agua reflejan cambios en las actividades humanas y las influencias ambientales.
- Es probable que las mejoras en el tratamiento de residuos municipales hayan contribuido a la reducción de bacterias y plomo.
- El aumento de las actividades agrícolas e industriales parece estar relacionado con el aumento de los niveles de nitrato, cloruro, arsénico y cadmio.
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