SEDIMENT CORE SAMPLING AND ANALYSIS OF KAW LAKE

Abstract

The Kaw Nation and Black land Research Center in July 2012 conducted a sediment core sampling from Kaw Lake. Kaw Lake is a reservoir constructed in 1976 by the Army Corps of Engineers for the purpose of water supply and recreation. It is located 11 miles east of Ponca City, Kay County, Oklahoma. This reservoir covers approximately 17,040 acres (69 km²) and is also known to be the seventh largest lake in Oklahoma by surface area. This lake holds 428,600 acre feet (528,700, 00 m³) of water which is said to be the ninth largest lake in Oklahoma. The lake is fed by the Arkansas River that flows from Colorado, through kansas and into Kaw Lake. The Arkansas River flows through Kaw Lake shared by several small creeks and empties into the Mississippi River. The purpose of the study was to determine the rate of sediment accumulation and examine the level of nutrient and heavy metals accumulation or deposition at the bottom of the lake. Four core samples from different parts of the lake at different depth were sampled for analysis. Each core sample was sectioned into 20 cm, dried and ground into homogenous powder. Samples from each section were tested for organic carbon content and heavy metals. Organic carbon content was verified by burning through a muffle furnace, while the remaining core samples were digested into a solution and ran through an Atomic Absorption Spectrophotometer (AAS) to evaluate the concentration of heavy metals. Particle size analyses were also determined. Results were organized by depth, concentration, particle size distribution and bulk density. Data showed phosphorous and some heavy metals concentrations at core 3 and 4 were higher than core 1 and 2. Phosphorous concentration at four sediment core sites ranged from 350 mg kg^-1 to 550 mg kg^-1. Whereas Aluminum concentration was 40,000 mg kg^-1 to 70,000 mg kg^-1, Barium 280 mg kg^-1 to 420 mg kg^-1, manganese 600 mg kg^-1 to 710 mg kg^-1, iron 30,000 mg kg^-1 to 48,000 mg kg^-1 are few to be cited. Bulk density, a measure of soil mass per unit of volume of soil in a water increased with water depth as the water content decreased.