title: Direct measurement of nutrient concentrations in freshwaters with a miniaturized analytical probe: evaluation and validation.
abstract: This work deals with the evaluation of the aqueous concentrations of dissolved reactive phosphorus (DRP), total phosphorus (TP), and ammonium nitrogen (N-NH4) in surface water by means of direct online instrumentation. A portable, submersible, and automated analyzer designed to measure dissolved and total nutrient concentrations characterized by miniaturization of the entire analytical process was tested against laboratory methods. A total number of 36 water samples of different origin (i.e., rain, river, lake, and sewage waters) were analyzed and used in the comparison of DRP, TP, and N-NH4data. Raw data were distributed in a broad range of concentrations: 5-299 μg P/L for DRP, 7-97 μg P/L for TP, and 11-332 μg N/L for N-NH4. Regression analysis underlined a high significant correlation between the measures of the probe and those of the laboratory (0.6 < R2< 0.9; p < 0.001) and pointed out the effectiveness of the new instrument in representing a broad range of nutrient concentrations.
authors.affiliation: National Research Council of Italy, Water Research Institute, UOS Brugherio, 20861, Brugherio, Italy. capo@unipv.it.
authors.forename: D
authors.initials: D
authors.lastname: Copetti
authors.affiliation: National Research Council of Italy, Water Research Institute, UOS Brugherio, 20861, Brugherio, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Valsecchi
authors.affiliation: Department of Civil Engineering & Architecture, University of Pavia, 27100, Pavia, PV, Italy.
authors.forename: A G
authors.initials: AG
authors.lastname: Capodaglio
authors.affiliation: National Research Council of Italy, Water Research Institute, UOS Brugherio, 20861, Brugherio, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Tartari
mesh_terms: D004784:Environmental Monitoring; D005618:Fresh Water / Q000032:analysis / Q000737:chemistry*; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D011891:Rain; D045483:Rivers; D012722:Sewage / Q000032:analysis; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D012722:Sewage; D014874:Water Pollutants, Chemical; D014867:Water; D010758:Phosphorus; D009584:Nitrogen
keywords: Field measurement; Miniaturized probe; Nutrients; Total phosphorus; Water pollution