Contribution of foliar leaching and dry deposition to sulfate in net throughfall below deciduous trees

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · Atmospheric Environment

DOI:https://doi.org/10.1016/0004-6981(88)90167-9· OSTI ID:978735

Garten, Jr, Charles T ^[1]; Bondietti, E A ^[2]; Lomax, Ronny D ^[1]

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1. ORNL
2. Oak Ridge National Laboratory (ORNL)

Experiments were conducted at Walker Branch Watershed, TN, in 1986 with radioactive {sup 35}S (87 day half-life) to quantify the contribution of foliar leaching and dry deposition to sulfate (SO{sub 4}{sup 2-}) in net throughfall (NTF). Two red maple (Acer rubrum) and two yellow poplar (Liriodendron tulipifera) trees (12-15 m tall) were radiolabeled by stem well injection. Total S and {sup 35}S were measured in leaves; {sup 35}S and SO{sub 4}{sup 2-} were measured in throughfall (THF). The contribution of foliar leaching to SO{sub 4}{sup 2-} in NTF, THF minus incident precipitation, was estimated by isotope dilution of {sup 35}S in NTF arising from nonradioactive S in dry deposition. The per cent contribution of foliar leaching to SO{sub 4}{sup 2-} in NTF was greatest during the week following isotope labeling and during the period of autumn leaf fall. During the growing season, foliar leaching accounted for < 20% and dry deposition accounted for > 80% of the SO{sub 4}{sup 2-} in NTF beneath the study trees. Dry deposition of S to these tree species can be reasonably approximated during summer from the measurement of SO{sub 4}{sup 2-} flux in NTF.

• Research Organization: Oak Ridge National Laboratory (ORNL); Oak Ridge National Environmental Research Park
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 978735
• Journal Information: Atmospheric Environment, Journal Name: Atmospheric Environment Journal Issue: 7 Vol. 22; ISSN ATENBP; ISSN 0004-6981
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
DECIDUOUS TREES
DEPOSITION
ISOTOPE DILUTION
LEACHING
MAPLES
POPLARS
PRECIPITATION
SULFATES
THROUGHFALL
TREES