Effect of acidity on nitrate reduction and denitrification in lower Coastal Plain soils. [North Carolina]

Journal Article · Sat Jan 01 00:00:00 EST 1983 · Soil Sci. Soc. Am. J.; (United States)

DOI:https://doi.org/10.2136/sssaj1983.03615995004700020014x· OSTI ID:6750363

Waring, S A; Gilliam, J W

Denitrification and nitrate reduction to NH/sub 4//sup +/-N and organic N were investigated in the laboratory using surface samples of Histosols and Ultisols. A wide range of pH (3.4 to 7.3) was obtained by liming acidic virgin soils and by selecting a range of field-limed soils. When incubated under waterlogged conditions in the presence of glucose for 2 d at 25/sup 0/C, there was a very low loss of NO/sub 3//sup -/-N below a pH of 4.0 and an increase in NO/sub 3//sup -/-N loss with pH up to a pH of 6.0. After 12 d of incubation, NO/sub 3//sup -/-N loss (105-115 mg L/sup -1/) was complete from soils at all pH values. Laboratory and field-limed soils behaved as expected from their pHs. For soils incubated for 2 d without glucose, there was a moderate effect of soil pH upon NO/sub 3//sup -/-N loss. For incubations longer than 2 d soluble C appeared to be more important than pH in controlling loss of NO/sub 3//sup -/-N. Soils with pH <4.0 showed unexpectedly high NO/sub 3//sup -/-N loss when incubated for periods >12 d without glucose. Experiments with /sup 15/NO/sub 3//sup -/-N showed that 16 to 20% of the NO/sub 3//sup -/-N loss in soils with pH <4.0 was due to reduction to NH/sub 4//sup +/-N and orgainc N but only 1 to 2% for soils with pH >4.0. Evidence indicates that the reduction was dissimilatory and unrelated to levels of soluble C. Denitrification was substantial in the soils with pH <4.0 and of a similar level to that for moderately acidic soils (pH 4.4-5.4). In the neutral soils (pH 6.9-7.3) denitrification was much higher but much of the increase appeared due to the higher level of soluble C.

• Research Organization: North Carolina State Univ., Raleigh
• OSTI ID: 6750363
• Journal Information: Soil Sci. Soc. Am. J.; (United States), Vol. 47
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ACIDIFICATION
ENVIRONMENTAL EFFECTS
NITRATES
REDUCTION
SOILS
DENITRIFICATION
PH VALUE
FERTILIZERS
GLUCOSE
LIMING
NORTH CAROLINA
ALDEHYDES
CARBOHYDRATES
CHEMICAL REACTIONS
FEDERAL REGION IV
HEXOSES
MONOSACCHARIDES
NITROGEN COMPOUNDS
NORTH AMERICA
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
SACCHARIDES
USA
510200* - Environment
Terrestrial- Chemicals Monitoring &amp; Transport- (-1989)