Foliar leaching, translocation, and biogenic emission of sup 35 S in radiolabeled loblolly pines

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Ecology; (USA)

DOI:https://doi.org/10.2307/1940263· OSTI ID:6077610

Garten, Jr, C T ^[1]

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1. Oak Ridge National Lab., TN (USA)

Foliar leaching, basipetal (downward) translocation, and biogenic emission of sulfur (S), as traced by {sup 35}S, were examined in a field study of loblolly pines. Four trees were radiolabeled by injection with amounts of {sup 35}S in the 6-8 MBq range, and concentrations in needle fall, stemflow, throughfall, and aboveground biomass were measured over a period of 15-20 wk after injection. The contribution of dry deposition to sulfate-sulfur (SO{sub 4}{sup 2{minus}}-S) concentrations in net throughfall (throughfall SO{sub 4}{sup 2{minus}}-S concentration minus that in incident precipitation) beneath all four trees was > 90%. Calculations indicated that about half of the summertime SO{sub 2} dry deposition flux to the loblolly pines was fixed in the canopy and not subsequently leached by rainfall. Based on mass balance calculations, {sup 35}S losses through biogenic emissions from girdled trees were inferred to be 25-28% of the amount injected. Estimates based on chamber methods and mass balance calculations indicated a range in daily biogenic S emission of 0.1-10 {mu}g/g dry needles. Translocation of {sup 35}S to roots in nongirdled trees was estimated to be between 14 and 25% of the injection. It is hypothesized that biogenic emission and basipetal translocation of S (and not foliar leaching) are important mechanisms by which forest trees physiologically adapt to excess S in the environment.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6077610
• Journal Information: Ecology; (USA), Journal Name: Ecology; (USA) Vol. 71:1; ISSN 0012-9658; ISSN ECOLA
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540111* -- Environment
Atmospheric-- Basic Studies-- Radiometric Techniques-- (1990-)
540211 -- Environment
Terrestrial-- Basic Studies-- Radiometric Techniques-- (1990-)
550501 -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID RAIN
ATMOSPHERIC PRECIPITATIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CANOPIES
CONIFERS
DAYS LIVING RADIOISOTOPES
DISSOLUTION
DISTRIBUTION
ELEMENTS
EVEN-ODD NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LEACHING
LEAVES
LIGHT NUCLEI
METABOLISM
NONMETALS
NUCLEI
PINES
PINOPHYTA
PLANTS
RADIOISOTOPES
RAIN
SEPARATION PROCESSES
SULFUR
SULFUR 35
SULFUR ISOTOPES
TISSUE DISTRIBUTION
TRACER TECHNIQUES
TRANSLOCATION
TREES