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USGS · 70013856

Relationships between water quality and phosphorus concentrations for Puget Sound region lakes

Robert J. Gilliom
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Abstract

Regression relationships were developed between summer mean total phosphorus (P) concentrations in near-surface water and both chlorophyll a concentrations and Secchi disc transparency for Puget Sound region lakes. Total P concentrations in the lakes studied ranged from 7 to 66 μ/L. The relationship between total P and chlorophyll a , based on data from 69 lakes, explained 57 percent of the variance in chlorophyll a . Predicted chlorophyll a concentrations and 95 percent confidence intervals ranged from 1 +3 -0.5 μg/L for 7 μg/L P to about +35 -10 μ/L for 66 μ/L P. The relationship between total P and Secchi disc, based on data from 71 lakes, explained 53 percent of the variance in Secchi disc. Predicted Secchi disc transparencies and 95 percent confidence intervals ranged from 5.5 +5.5 -3.0 m for 7 μ/L P to 1.4 +1.5 -0.7 m for 66 μ/L P.

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BibTeXRIS

Robert J. Gilliom. 2007-06-08. Relationships between water quality and phosphorus concentrations for Puget Sound region lakes. https://doi.org/10.1111/j.1752-1688.1984.tb04726.x

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