title: A low cost method to estimate dissolved reactive phosphorus loads of rivers and streams.
abstract: Concentration of dissolved reactive phosphorus ([DRP]) in rivers changes periodically (daily, weekly, seasonally) and is dependent on the weather and discharge Q. Accordingly, accurate estimation of the annual DRP load requires intensive sampling if not even continuous monitoring, which is laborious and expensive. We present a new, elaborated low cost technique based on passive samplers (P-traps), describing their design and chemical analysis. P-traps use iron(oxy)hydroxide as a sorbent, are inexpensive, easy to handle, and can be exposed for several months. We compare average DRP concentrations obtained from spot samples and P-traps and discuss the applicability and accuracy of the suggested method to measure annual P loads of rivers characterized by highly variable DRP concentrations.
authors.affiliation: Swiss Federal Institute for Environmental Science and Technology, Eawag, CH-6047, Kastanienbaum, Switzerland. beat.mueller@eawag.ch
authors.forename: Beat
authors.initials: B
authors.lastname: Müller
authors.forename: Arno
authors.initials: A
authors.lastname: Stöckli
authors.forename: Ruth
authors.initials: R
authors.lastname: Stierli
authors.forename: Ernst
authors.initials: E
authors.lastname: Butscher
authors.forename: René
authors.initials: R
authors.lastname: Gächter
mesh_terms: D004784:Environmental Monitoring / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D010758:Phosphorus / Q000032:analysis*; D015203:Reproducibility of Results; D045483:Rivers; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D014873:Water Pollutants; D010758:Phosphorus