Heavy metal pollution in the Guadiamar River and the Guadalquivir estuary (south west Spain)

Abstract

The Guadalquivir river is the most important course of water of South West Spain. Its tributary, the Guadiamar river, joins the Guadalquivir near its mouth at C~diz Gulf in the Spanish South Atlantic coast, just after skirting the marshy part of the Do~ana National Park. The upper Guadiamar river receives through its tributary the Agrio river the drainage water from an opencast-worked polymetallic sulphide deposit and the effluents from a plant for the treatment and concentration of mineral. Guadiamar river also receives sewaEes outlets from villages supporting a population of ca. 40000 and diffuse land pollution. Untreated effluents from olive-oil manufacturing mills were also discharged into the river during the first part of the period of this study. To preserve the Do~ana National Park from water pollution, Guadiamar river flows between levees in the neighbourhood of the Park, what causes droughts and other problems of ecological significance. However, there exists a project to allow Guadiamar river to flood the marshes of the Park again. C~diz Gulf is rich in high quality fish and shell-fish and touristic resorts. Also C~diz Gulf and Guadalquivir estuary are important areas for the development of aquaculture. The Do~ana National Park, the Guadalquivir estuary and the C~diz Gulf, are very fragile ecosystems which can be greatly altered by inflow of sewage and industrial effluents. The present paper summarizes the work carried out from 1978 to 1984 on water, sediment, flora and fauna of the Guadiamar river and the Guadalquvir estuary.