Quality of Ozark streams and ground water, 1992-95

Summary of surface-water quality data from the Illinois River Basin in Northeast Oklahoma, 1970-2007

“…Trace element concentrations in water are generally low in this basin. Forested areas of the region typically have the best water quality, with agricultural and urban land uses contributing greater amounts of nutrients, pesticides, and fecal-indicator bacteria to water in streams and aquifers others, 1999a and1999b). Median concentrations of the major ions-calcium, magnesium, sodium, potassium, bicarbonate, chloride, and sulfate-were similar between sites sampled in the basin (fig.…”

“…20), although single-celled suspended algae such as diatoms also may increase turbidity of streams. Agricultural areas in the Ozarks region tend to contribute greater concentrations of nutrients to streams than forested areas and have fewer trees shading stream channels, contributing to increased growth of periphyton and increased abundance of species of fish known as stonerollers, that graze on streambed periphyton (Peterson andothers, 1999a and1999b;and Petersen and Femmer, 2002). Filamentous, nitrogen-fixing blue-green algae of the genus Calothrix (fig.…”