Sulfur release and retention in forest soil organic matter. [Pseudotsuga menziessii; Alnus rubra Bong]

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:7068275

Homann, P S

Sulfur (S) release and retention in decomposing forest litter and humidified soil organic matter were examined in adjacent 55-year-old stands of Douglas-fir (Pseudotsuga menziessii (Mirb.) Franco) and red alder (Alnus rubra Bong). Fresh Douglas-fir and red alder litter had similar concentrations of total S (1220 and 1380 mg S {times} kg{sup {minus}1}, respectively), but the different distribution among four chemical forms (inorganic SO{sub 4}, soluble C-bonded S, ester SO{sub 4}, and insoluble C-bonded S) led to different S losses during decomposition. The initially high mass of inorganic SO{sub 4} was leached from Douglas-fir litter within four months. This resulted in greater S loss than from red alder litter, where insoluble C-bonded S was the major S fraction. Leaching of initially present soluble C-bonded S also contributed significantly to S loss. Concentration of SO{sub 4} (4 vs 0 mg S {times} L{sup {minus}1}) in solutions applied over a one-year period to green Douglas-fir needles decomposing in the forest had no effect on dynamics of insoluble C-bonded S and ester SO{sub 4}. High concentration of SO{sub 4} (32 vs. 0 mg S {times} L{sup {minus}1}) in solutions applied to Douglas-fir needle litter decomposing for 110 days at 22{degree}C resulted in higher insoluble C-bonded S retention only when high concentration of NH{sub 4}NO{sub 3} (112 vs 28 N {times} L{sup {minus}1}) was also in the added solutions. Addition of N alone caused formation of both insoluble organic N and insoluble C-bonded S. Higher initial concentration of insoluble C-bonded S in green needles decomposing in the forest did not affect the S mass remaining after one year. Addition of SO{sub 4} (38 mg S {times} kg soil{sup {minus}1}) to manipulated soil samples from Douglas-fir and red alder A horizons decreased net S mineralization. There was no effect of SO{sub 4} addition on arylsulfatase activity.

• Research Organization: Washington Univ., Seattle, WA (USA)
• OSTI ID: 7068275
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
BIOLOGICAL MATERIALS
CHEMICAL REACTIONS
CONIFERS
DATA
DECOMPOSITION
DISSOLUTION
ELEMENTS
EXPERIMENTAL DATA
FIRS
FOREST LITTER
FORESTS
INFORMATION
LEACHING
MATERIALS
MINERALIZATION
NITROGEN
NONMETALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PINOPHYTA
PLANTS
RETENTION
SEPARATION PROCESSES
SOILS
SULFATES
SULFUR
SULFUR COMPOUNDS
SULFUR CYCLE
THROUGHFALL
TREES