Regulation of nitrification in upland forest soils

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6860218

Donaldson, J M

Forest soils often have low nitrate levels and are slow to produce NO/sub 3//sup -/-N when incubated in the laboratory or after site disturbance. Several hypotheses have been proposed to explain the patterns of nitrification that have been observed in forests ecosystems. These hypotheses suggest that nitrification is limited by low soil pH, NH/sub 4//sup +/-N availability, the presence of allelopathic inhibitors or low levels of other nutrients, such as phosphorus. In this study, experiments were designed to determine if nitrate production in forest soils is regulated by soil pH, NH/sub 4//sup +/ of allelopathic compounds. Three sites representing secondary succession in upland oak-hickory forests were sampled five times during a one-year period. Sampling dates coincided with important stages in the phenological development of the site vegetation. Soils were incubated for up to six weeks in the laboratory. This allowed accurate definition of the potential for nitrogen mineralization and nitrification. Results of laboratory incubation and field-treatment experiments indicate that HN/sub 4//sup +/-N availability is the main factor regulating NH/sub 4//sup +/-oxidizer populations and nitrification in the forest soils investigated. Ammonium is the substrate of nitrification.

• Research Organization: Missouri Univ., Columbia (USA)
• OSTI ID: 6860218
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
FORESTS
SOILS
NITRIFICATION
AMMONIUM COMPLEXES
NUTRIENTS
OXIDIZERS
PH VALUE
TERRESTRIAL ECOSYSTEMS
CHEMICAL REACTIONS
COMPLEXES
ECOSYSTEMS
510200* - Environment
Terrestrial- Chemicals Monitoring & Transport- (-1989)
500200 - Environment
Atmospheric- Chemicals Monitoring & Transport- (-1989)