Record Display for the EPA National Library Catalog

RECORD NUMBER: 10 OF 13

Main Title Summer Internal Phosphorus Supplies in Shagawa Lake, Minnesota.
Author Larsen, D. P. ; Schults, D. W. ; Malueg, K. W. ;
CORP Author Corvallis Environmental Research Lab., OR.
Year Published 1981
Report Number EPA/600/J-81/400;
Stock Number PB85-244234
Additional Subjects Phosphorus ; Water pollution ; Shagawa Lake ; Sediments ; Summer ; Chemical properties ; Anaerobic processes ; Depth ; Concentration(Composition) ; Biological productivity ; Reprints ;
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
NTIS  PB85-244234 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 16p
Abstract
Phosphorus budget calculations for Shagawa Lake show that significant increases in lake P during July and August 1971-1975 originated from within the lake basin. Mass increases of 2,000-2,900 kg (35-50 ug/liter) were measusred, corresponding to internal supply rates of 240-680 kg/wk over a 3-9 week interval. After anaerobic conditions developed in late June, release from the profundal zone sediments contributed significant amounts of P to lake water. Sediment chemical properties were determined to estimate the size of the P reservoir in the profundal zone. Although external sources of phosphorus have been reduced by about 80% the feedback of P from the sediments is supporting the productivity of Shagawa Lake and may continue to do so for many years.