Comparison of nutrient and contaminant fluxes in two areas with different hydrological regimes (Empordà Wetlands, NE Spain)

• Published in: Water research (Oxford) Vol. 37; no. 12; pp. 3034 - 3046
• Main Authors: López-Flores, Rocı́o, Quintana, Xavier D, Salvadó, Victoria, Hidalgo, Manuela, Sala, Lluis, Moreno-Amich, Ramon
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-07-2003; Elsevier Science
• Subjects: Applied sciences; Brackish; Confinement; Continental surface waters; Earth sciences; Earth, ocean, space; Ecosystem; Engineering and environment geology. Geothermics; Environmental Monitoring; Exact sciences and technology; Geologic Sediments - chemistry; Heavy metals; Mediterranean; Mediterranean wetlands; Metals, Heavy - analysis; Natural water pollution; Nitrogen - analysis; Non-point source pollution; Pesticides; Pesticides - analysis; Phosphorus - analysis; Pollution; Pollution, environment geology; Spain; Water Movements; Water Pollutants, Chemical - analysis; Water treatment and pollution; Europe; Spain; Spain, Emporda Wetlands; Mediterranean Region; Confinement; Non-point source pollution; Mediterranean wetlands; Heavy metals; Pesticides; Diffuse source; Pollutant behavior; Surface water; Marsh; Nutrient; Water pollution; Wetland; Heavy metal
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/S0043-1354(03)00109-X

Nutrient (N and P), heavy metal (Ni, Cd, Cr, Cu and Pb) and pesticide (DDT, DDD, DDE, lindane, aldrin, endrin, dieldrin, permethrin, atrazine and simazine) concentrations in water and sediment were analysed in the Empordà Wetlands, a Mediterranean wetland area in NE Spain. Mean nutrient and contaminant concentrations and input and output loads via tributaries were compared in two marshes with different water turnover: a freshwater marsh (FWM), with a high water turnover rate due to continuous surface water inputs and outputs, and a brackish water marsh (BWM), with lower turnover and no continuous surface output, where water remains confined during dry periods. Mean concentrations of most heavy metals exceeded the maximum permissible concentration (MPC) in BWM, whilst only some pesticides reached MPC in FWM. The confined waters of BWM showed higher sensitivity to contaminant input loadings than FWM due to the lack of continuous water outputs. Non-point source pollution inputs during runoff (mainly in FWM) and concentration during confinement (mainly in BWM) showed as the main environmental problems related to nutrients and contaminants in these ecosystems. Thus, the importance of confinement and its effect on pollutant concentrations must be borne in mind to achieve correct management of Mediterranean wetlands.