| Summary: | Throughout 2015-2017, sediment traps were deployed in Lakes Peters and Schrader to measure the rate of deposition and collect suspended sediments in the lakes. In 2015, three pairs of static (i.e., non-automated) traps with different aspect ratios (different collection-tube heights but same collection-tube diameters) were deployed from May-August at a central location of Lake Peters to determine the effect of these proportions on sediment collection efficiency. In May-August 2016, one static trap was deployed in Lake Peters, two sets in Lake Schrader, and one set in a small pond on the southwestern edge of Lake Schrader ("Schrader Pond"). The same traps were also deployed for a full year from August 2016-August 2017. These traps consisted of ordinary 2 Liter plastic bottles with the bottoms removed, a 50 milliliter centrifuge tube secured to its mouth, and inverted to funnel sediments into the tubes. Each trap comprised two or three replicate tubes/bottles deployed at different depths along an anchored mooring. In addition, an incrementing sediment trap was deployed from May 2016 through August 2017, collecting sediments in 23 bottles rotating over daily to weekly increments. The last sample of these 23 increments should be interpreted cautiously, as there is evidence that excess sediments sluffed off into the bottle upon trap retrieval. This trap design is described in the following study: Muzzi, R.W. and Eadie, B.J., 2002. The design and performance of a sequencing sediment trap for lake research. Marine Technology Society Journal, 36, 2–28. For all sediment samples, dry sediment mass, daily flux, and annual flux were calculated. For several static trap samples, grain size data (mean, SD, d50, d90, %sand, %silt, and %clay) were determined using a Coulter LS-320 following diatom removal. Organic matter content was determined using loss on ignition analysis.
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