Hydrology and nitrogen distribution in claypan soil and glacial till near Centralia, Missouri

Conference · Mon Mar 01 04:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5074719

Kelly, B P; Blevins, D W ^[1]

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1. Geological Survey, Independence, MO (United States)

Background data were collected from May 1991 to May 1992 on a 380-square meter research plot near Centralia, Missouri. At the plot, loess and glacial drift underlie 45 centimeters of topsoil and 60 centimeters of low-permeability claypan. Most recharge to ground water occurred between October and April. Gravity lysimeter data indicate that preferential flow through the unsaturated zone is an important mechanism for ground-water recharge and chemical transport. Rainfall totaled 96 centimeters and depth to the water table ranged from 1 to 2.2 meters below ground surface. Nitrate nitrogen concentrations (in milligrams per liter) ranged from 0.15 to 0.63 in rainfall, 0.65 to 3.7 in surface runoff, 9.6 to 130 in unsaturated-zone water, 14 to 46 in shallow ground water (less than 9 meters), and 1.2 to 2.5 in deeper ground water (greater than 15 meters). Enrichment of nitrogen-15 relative to atmospheric nitrogen ranged from +9.7 to +13.5 permil in nitrate nitrogen from shallow ground water and from +3.8 to +8.7 permil for all nitrogen species in soil. Ground-water samples analyzed for tritium indicate that shallow ground water may be substantially younger than deeper ground water. In May 1992 fertilizer spiked with nitrogen-15 and bromide was applied to the research plot. Movement of these tracers will be monitored to determine the role of preferential flow in nitrogen transport through the unsaturated zone and the contribution of nitrate from fertilizers to ground water and surface runoff.

• OSTI ID: 5074719
• Report Number(s): CONF-9303210--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:3
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540210 -- Environment
Terrestrial-- Basic Studies-- (1990-)
540220 -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
58 GEOSCIENCES
580000* -- Geosciences
CHEMICAL COMPOSITION
CHEMISTRY
DEVELOPED COUNTRIES
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
GEOCHEMISTRY
GEOLOGIC DEPOSITS
GROUND WATER
HYDROGEN COMPOUNDS
HYDROLOGY
MASS TRANSFER
MISSOURI
MORAINES
NITRATES
NITROGEN COMPOUNDS
NORTH AMERICA
OXYGEN COMPOUNDS
RECHARGE
USA
WATER
WATER CHEMISTRY