Sediment Phosphorus Flux at Lake Tenkiller, Oklahoma: How Important Are Internal Sources?. Issue 1 (1st August 2017)

• Record Type: Journal Article
• Authors: Lasater, A. L.; Haggard, B. E.
• Is Part Of: Agricultural & environmental letters. Volume 2:Issue 1(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-08-01
• Subjects: Agriculture -- Periodicals; Agriculture -- Environmental aspects -- Periodicals; Agriculture; Agriculture -- Environmental aspects; Periodicals; 630
• DOI: 10.2134/ael2017.06.0017
• Languages: English
• ISSNs: 2471-9625

Abstract

Abstract : 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.