Open AccessSediment Phosphorus Flux at Lake Tenkiller, Oklahoma: How Important Are Internal Sources?
Author(s) -
Lasater A. L.,
Haggard B. E.
Publication year - 2017
Publication title -
agricultural and environmental letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.681
H-Index - 12
ISSN - 2471-9625
DOI - 10.2134/ael2017.06.0017
Subject(s) - eutrophication , sediment , watershed , hydrology (agriculture) , environmental science , flux (metallurgy) , phosphorus , geology , nutrient , ecology , geomorphology , chemistry , geotechnical engineering , organic chemistry , machine learning , computer science , biology
Core Ideas Sediment P release needs to be measured in lakes and reservoirs that are eutrophic. Sediment P release data is essential for calibrating lake and reservoir models used in a TMDL. Sediment P release at Lake Tenkiller was very high relative to that predicted by the model. Sediment P release was also very high relative to that observed in regional reservoirs. Internal P sources need to be addressed in watershed management strategies.Watershed management for lakes and reservoirs largely focuses on external sources, but internal sources, such as sediment P release, can be important. This study quantified sediment P release in Lake Tenkiller, Oklahoma, in summer 2016. Eight intact sediment–water cores were collected from the riverine and transition zone and then incubated at 22°C for 8 d under aerobic and anaerobic conditions. Phosphorus mass in the overlying water of all cores increased with time, and the rate of increase was significantly greater under anaerobic conditions. Sediment P release was reflective of eutrophic and hypereutrophic conditions, measuring up to 15.2 mg m −2 d −1 . Sediment P fluxes were four to five times greater than the net flux predicted by the model of Lake Tenkiller, suggesting that internal P sources need to be considered in the total maximum daily load process.