| Abstract: | Predictive regression relationships between concentrations of total phosphorus (P) in near-surface waters (1m) and water-quality characteristics were developed for lakes in the Puget Sound region. Nitrogen-to-phosphorus ratios support the strategy of emphasizing total P for lake eutrophication assessment within the range of lake conditions represented. Relationships based on summer total P concentrations, rather than winter-spring total P, led to more successful prediction of mean summertime chlorophyll a concentrations and Secchi-disc transparencies. The 78 lakes evaluated in the study had an average mean concentration of total phosphorus in near-surface waters of 22 ?g/L during the summer with mean concentrations for individual lakes ranging from 7 to 76 ?g/L. For regression relationships based on summer total phosphorus concentrations, the standard error of predicted Secchi-disc transparencies is ?0.9 meters for phosphorus concentrations of 15 ?g/L or greater, and the standard error of predicted chlorophyll a concentrations is ?5 ?g/L. Predictions for the range of conditions evaluated favorably agreed with predictions from similar relationships developed by other researchers for different lakes. To supplement estimates of transparency and chlorophyll a from regression relationships, a broader system of water-quality groups, including recreational suitability and fish habitat quality, was developed from published information and our experience in the region. |
| Genre: | USGS Numbered Series |
| ProdID: | 9137 |
| Citation Author: | Gilliom, Robert J.; Bortleson, Gilbert Carl |
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| Citation Language: | ENGLISH |
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| Citation Phsyical Description: | 29 p. ill., map ;28 cm. |
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| Citation Publisher: | U.S. Geological Survey, |
| Citation Series: | Open-File Report |
| Citation Series Code: | OFR |
| Citation Series Number: | 83-255 |
| Citation Search Results Text: | Relationships between water quality and phosphorus concentrations for lakes of the Puget Sound region, Washington; 1983; OFR; 83-255; Gilliom, Robert J.; Bortleson, Gilbert Carl |
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| Citation Year: | 1983 |
| Type: | citation/reference |
| Text: | Relationships between water quality and phosphorus concentrations for lakes of the Puget Sound region, Washington; 1983; OFR; 83-255; Gilliom, Robert J.; Bortleson, Gilbert Carl |
| URL (THUMBNAIL): | http://pubs.usgs.gov/of/1983/0255/report-thumb.jpg |
| URL (DOCUMENT): | http://pubs.usgs.gov/of/1983/0255/report.pdf |
| Date Other: | Sat, 1 Jan 1994 00:00 -0600 |
| Publisher: | U.S. Geological Survey, |
