Emission of nitric oxide (NO) from tropical forest soils and exchange of NO between the forest canopy and atmospheric boundary layers

Journal Article · Thu Sep 20 00:00:00 EDT 1990 · Journal of Geophysical Research; (USA)

DOI:https://doi.org/10.1029/JD095iD10p16755· OSTI ID:6100421

Bakwin, P S; Wofsy, S C; Fan, Songmiao ^[1]; Keller, M ^[2]; Trumbore, S E ^[3]; Da Costa, J M

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1. Harvard Univ., Cambridge, MA (USA)
2. Princeton Univ., NJ (USA)
3. Lamont-Doherty Geophysical Observatory, Palisades, NY (USA)

Emissions of NO from soils in the Amazon rain forest were measured at 66 locations (224 measurements) using an enclosure technique, and continuous vertical profiles of NO and O{sub 3} were measured between the ground and 41-m altitude. Fluxes of NO averaged 8.9 ({plus minus}1.5) {times} 10{sup 9} molecules cm{sup {minus}2} s{sup {minus}1} from the dominant (yellow clay) soils of the region, with larger fluxes (33.7 ({plus minus}6.5) {times} 10{sup 9} molecules cm{sup {minus}2} s{sup {minus}1}) observed from adjacent white sand soils. Fluxes from clay soils were lower by more than a factor of 5 than fluxes observed during the dry season at a nearby site. Low soil emission rates were reflected in lower concentrations of NO at the top of the forest canopy in the west season, only 30-50 pptv (parts per trillion by volume) during the daytime. The measured fluxes are consistent with chemical mass balances for NO within the forest canopy, calculated from the NO and O{sub 3} profiles taken at night, and with observations of NO between 150 and 5,000 m altitude. Measurements of NO emission rates from soil plots fertilized using NaNO{sub 3}, NH{sub 4}Cl or sucrose indicated that a reductive pathway (denitrification) may have been primarily responsible for production of the NO released by both clay and sand soils.

• OSTI ID: 6100421
• Journal Information: Journal of Geophysical Research; (USA), Vol. 95:D10; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
BRAZIL
AIR POLLUTION
NITRIC OXIDE
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
OZONE
SOILS
DEGASSING
ALTITUDE
AMAZON RIVER
BOUNDARY LAYERS
CANOPIES
CLAYS
DAILY VARIATIONS
DENITRIFICATION
EARTH ATMOSPHERE
EMISSION
FERTILIZERS
FORESTS
MASS BALANCE
SAND
SEASONAL VARIATIONS
CHALCOGENIDES
CHEMICAL REACTIONS
DEVELOPING COUNTRIES
LATIN AMERICA
LAYERS
MASS TRANSFER
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
POLLUTION
RIVERS
SOUTH AMERICA
STREAMS
SURFACE WATERS
VARIATIONS
540120* - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)
540220 - Environment
Terrestrial- Chemicals Monitoring & Transport- (1990-)