The contribution of roadside soil to phosphorus loading in the eutrophic Lagos Lagoon, Nigeria
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Date
2011-05-11
Authors
Abayomi, A. A.
Nimmo, M.
Williams, C.
Olayinka, K. O.
Osuntogun, B. A.
Alo, B. I.
Worsfold, P. J.
Journal Title
Journal ISSN
Volume Title
Publisher
pubs.rsc.org
Abstract
Roadside soils were sampled from the Lagos Lagoon catchment during the wet and dry seasons over
the period 2005–2009. Lagoon sediment samples were also collected within the same period. All
samples were digested with aqua regia to determine total phosphorus and extracted with 0.5 M sodium
bicarbonate to determine the bioavailable fraction (Olsen-P). A segmented flow analyser method was
used for analysis and good accuracy was demonstrated for two reference soils (SO-2 from CCMET and
SRM 2711 from NIST). The Lagos Lagoon is a hypereutrophic water body (1270 1170 mgPL 1
),
with significant areas of anoxia and water hyacinth growth. The total phosphorus concentrations in
roadside soils (16 sites; mean 2 S.D.) were 285 279 mg kg 1 in the wet season and 424 629 mg kg 1
in the dry season, indicating that rainwater leaching is a major source of phosphorus in the lagoon. The
bioavailable fractions were 5.17 3.47 mg kg 1 (2.1 1.5% of the total) in the wet season and 13.0
8.7 mg kg 1 (4.3 4.5% of the total) in the dry season.
Description
Staff Publication
Keywords
Research Subject Categories::NATURAL SCIENCES::Chemistry::Analytical chemistry::Separation methods , Lagoon sediment , total phosphorus , segmented flow analyser method , anoxia , water hyacinth growth
Citation
Abayomi, A. [Et..al], (2011). The contribution of roadside soil to phosphorus loading in the eutrophic Lagos Lagoon, Nigeria. Journal of Environmental Monitoring, Vol.13(7), 1884-1889pp.