title: A critical re-evaluation of the prediction of alkalinity and base cation chemistry from BGS sediment composition data.
abstract: The model of Begum et al. (2010) that predicts alkalinity and Ca and Mg concentrations in river water from available sediment composition data has been critically re-evaluated using an independent validation data set. The results support the hypothesis that readily available stream water sediment elemental composition data are useful for prediction of mean and minimum concentrations of alkalinity and Ca and Mg in river water throughout the River Derwent catchment in North Yorkshire without requiring land-use data inputs as stream water sediment composition reflects all aspects of the riparian zone soil system, including land-use. However, it was shown for alkalinity prediction that rainfall exerts a significant dilution effect and should be incorporated into the model in addition to flow path-weighted sediments Ca% and Mg%. The results also strongly suggest that in catchments with substantial rough moorland land-use neutralization of organic acids consumes alkalinity and this fact should be considered in any future development of the model.
authors.affiliation: Environmental Sciences Department, Fatima Jinnah Women University, The Mall, Rawalpindi, Pakistan; Environment Department, University of York, Heslington, York, UK. Electronic address: shaheen_bakht@yahoo.com.
authors.forename: S
authors.initials: S
authors.lastname: Begum
authors.affiliation: Environment Department, University of York, Heslington, York, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: McClean
authors.affiliation: Environment Department, University of York, Heslington, York, UK.
authors.forename: M S
authors.initials: MS
authors.lastname: Cresser
authors.affiliation: Department of Botany, Kohat University of Science and Technology, 26000 Kohat, Pakistan.
authors.forename: M
authors.initials: M
authors.lastname: Adnan
authors.affiliation: British Geological Survey, Keyworth, Nottingham NG12 5GG, UK.
authors.forename: N
authors.initials: N
authors.lastname: Breward
mesh_terms: D002412:Cations / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D045483:Rivers / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002412:Cations; D014874:Water Pollutants, Chemical
keywords: Alkalinity; Calcium/magnesium; Predict; Rainfall; River Derwent; River sediment