Sediment phosphorus cycling in a shallow lake: spatio-temporal variations in phosphorus pools and release

B.M Spears, L. Carvalho, R. Perkins, A. Kirika, David Maxwell Paterson

Research output: Contribution to journalArticlepeer-review

106 Citations (Scopus)

Abstract

Sediment and water column phosphorus fractions were recorded monthly for one year (April 2004-April 2005) in a shallow lake recovering from nutrient pollution (Loch Leven, Scotland). Equilibrium phosphate concentration (EPC0) and gross sediment phosphorus (P) release rates were estimated from laboratory experiments. Pore water and organic P pools were lowest during warm water periods whereas bottom water P was lowest during cold water periods. Reductant-soluble, organic, metal oxide-adsorbed, residual and sediment total phosphorus pools all varied significantly with overlying water depth. Short-term, high magnitude, redox initiated P release events occurred in late summer and winter as a result of anoxic sediment conditions. Lower magnitude long-term release conditions were maintained for most of the year, most likely as a result of organic P cycling and maintenance of high concentration gradients between the pore and bottom water P pools. Estimates of summer P uptake/release rates, across an intact sediment-water interface, suggested that maximum gross internal release was similar to 12 mg SRP m(-2) lake surface area d(-1) with EPC0 values ranging between 180 and 270 mu g P L-1. This study highlights the biological mediation of internal loading in shallow eutrophic lakes, and in particular, the role of sediment algae in decreasing, and sediment bacteria in enhancing, sediment P release.

Original languageEnglish
Pages (from-to)37-48
Number of pages12
JournalHydrobiologia
Volume584
Issue number1
DOIs
Publication statusPublished - Jun 2007

Keywords

  • sediment
  • phosphorus
  • mobility
  • bio-regulation
  • seasonality
  • DISSOLVED SUBSTANCES
  • WATER INTERFACE
  • RESTORATION
  • EXCHANGE
  • RECRUITMENT
  • ECHINULATA
  • MANAGEMENT
  • MOBILITY
  • COLUMN
  • FLOW

Fingerprint

Dive into the research topics of 'Sediment phosphorus cycling in a shallow lake: spatio-temporal variations in phosphorus pools and release'. Together they form a unique fingerprint.

Cite this