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Análisis de la producción de sedimentos en una cuenca con un sistema de información geográfica. El sistema Cubillas-Colomera

01/2000;
Source: OAI

ABSTRACT En este trabajo se analiza la producción de sedimentos en las cuencas de los ríos Cubillas y Colomera, afluentes del río Genil, que tienen los embalses conectados. Para ello se ha aplicado la ecuación universal de pérdida de suelo sobre las celdillas de una gran retícula en la que se han dividido las cuencas, abordando el estudio en un sistema de información geográfica. La circulación de sedimentos se basa en los coeficientes de entrega definidos en función del tiempo de viaje por la superficie de la cuenca, propuesta por Dickinson y Rudra (1990) en el modelo GAMES, adaptándola en algunos aspectos al método propuesto. Una vez validado el modelo, mediante la comparación de los resultados obtenidos con los recogidos en la bibliografía, y ante la imposibilidad de realizar una correcta calibración del mismo al no existir datos experimentales suficientes, se ha realizado un análisis de sensibilidad con el propósito de estimar el nivel de error introducido en los resultados del modelo, ante variaciones de su parámetro principal. Finalmente, se han simulado diferentes situaciones para localizar las zonas más susceptibles de mejora con diferentes prácticas de conservación, concluyéndose que el método estima bien los niveles erosivos de las cuencas, y las cantidades de sedimento aportadas a sus respectivos embalses. Además se ha determinado el valor umbral del llamado factor de cubierta por encima del cual es preferible un cambio de manejo del suelo frente a la protección directa de cauces fluviales, para disminuir el sedimento recibido por los embalses.

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