Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/28/2004
Publication Date: 10/1/2004
Citation: Alberts, E.E., Sadler, E.J. 2004. Long-term streamflow characteristics from a claypan soil watershed. [abstract] [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts.
Technical Abstract: Planning best management practices to improve surface water quality and assess impacts requires streamflow characteristics be known. Objectives were to: i) characterize long-term annual and seasonal variations in streamflow and ii) compare streamflow from a 12-year period with surface water quality data to the previous 20-year period with only streamflow data. In 1970, the 7,250-ha Goodwater Creek watershed in north-central Missouri was instrumented. Soils are primarily claypan soils, with about 90% of the watershed cropped. Most streamflow in Goodwater Creek is surface runoff, with less than 5% recharge from ground water. For 1971-2002, annual precipitation values were normally distributed (mean 942 mm, range 850 mm.) Annual streamflow values were also normally distributed (mean 319 mm, range 726 mm.) Mean streamflow values for spring, summer, fall, and winter were 134, 58, 45, and 82 mm. Mean annual streamflow for 1991-2002 was 31% higher than for 1971-1990, but with only 3% higher precipitation. Much of the higher discharge occurred during the spring when agricultural chemicals are applied. Streamflow from this large agricultural watershed was highly variable within and among years. Streamflow differences that can occur between two relatively long periods of record make measuring the impact of new management practices on surface water quality quite challenging.