title: Effect of flood events on transport of suspended sediments, organic matter and particulate metals in a forest watershed in the Basque Country (Northern Spain).
abstract: An understanding of the processes controlling sediment, organic matter and metal export is critical to assessing and anticipating risk situations in water systems. Concentrations of suspended particulate matter (SPM), dissolved (DOC) and particulate (POC) organic carbon and metals (Cu, Ni, Pb, Cr, Zn, Mn, Fe) in dissolved and particulate phases were monitored in a forest watershed in the Basque Country (Northern Spain) (31.5km(2)) over three hydrological years (2009-2012), to evaluate the effect of flood events on the transport of these materials. Good regression was found between SPM and particulate metal concentration, making it possible to compute the load during the twenty five flood events that occurred during the study period at an annual scale. Particulate metals were exported in the following order: Fe>Mn>Zn>Cr>Pb>Cu>Ni. Annual mean loads of SPM, DOC and POC were estimated at 2267t, 104t and 57t, respectively, and the load (kg) of particulate metals at 76 (Ni), 83 (Cu), 135 (Pb), 256 (Cr), 532 (Zn), 1783 (Mn) and 95170 (Fe). Flood events constituted 91%-SPM, 65%-DOC, 71%-POC, 80%-Cu, 85%-Ni, 72%-Pb, 84%-Cr, 74%-Zn, 87%-Mn and 88%-Fe of total load exported during the three years studied. Flood events were classified into three categories according to their capacity for transporting organic carbon and particulate metals. High intensity flood events are those with high transport capacity of SPM, organic carbon and particulate metals. Most of the SPM, DOC, POC and particulate metal load was exported by this type of flood event, which contributed 59% of SPM, 45% of organic carbon and 54% of metals.
authors.affiliation: Department of Chemical and Environmental Engineering, School of Engineering of Bilbao, University of the Basque Country (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao, Spain; School of Health Technologies, Faculty of Medicine, University of Costa Rica, Rodrigo Facio Campus, San Pedro de Montes de Oca, San José, Costa Rica.
authors.forename: M
authors.initials: M
authors.lastname: Peraza-Castro
authors.affiliation: University of Toulouse, INPT, UPS, Laboratoire Ecologie Fonctionnelle et Environnement (Ecolab), Avenue de l'Agrobiopole, 31326 Castanet Tolosan Cedex, France; CNRS, Ecolab, 31326 Castanet Tolosan Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Sauvage
authors.affiliation: University of Toulouse, INPT, UPS, Laboratoire Ecologie Fonctionnelle et Environnement (Ecolab), Avenue de l'Agrobiopole, 31326 Castanet Tolosan Cedex, France; CNRS, Ecolab, 31326 Castanet Tolosan Cedex, France.
authors.forename: J M
authors.initials: JM
authors.lastname: Sánchez-Pérez
authors.affiliation: Department of Chemical and Environmental Engineering, School of Engineering of Bilbao, University of the Basque Country (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao, Spain. Electronic address: estilita.ruiz@ehu.es.
authors.forename: E
authors.initials: E
authors.lastname: Ruiz-Romera
mesh_terms: D004784:Environmental Monitoring; D055868:Floods; D019015:Geologic Sediments / Q000032:analysis*; D008670:Metals / Q000032:analysis*; D052638:Particulate Matter / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D013030:Spain; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D008670:Metals; D052638:Particulate Matter; D014874:Water Pollutants, Chemical
keywords: Flood event; Forest catchment; Organic matter; Suspended particulate matter; Trace metals