Organic Sulfur in Throughfall, Stemflow, and Soil Solutions from Temperate Forests
Canadian Journal of Forest Research
National Research Council Canada
In the assessment of S cycling in forest ecosystems, solutions passing through the forests are normally analyzed for inorganic SO4; other forms of S are rarely considered. In this study, organic S (estimated as the difference between total S and SO4-S) was measured in canopy and soil solutions from eight forest stands spanning a broad range of overstory and soil types. Organic-S concentrations varied among the different types of solutions and among the forests, with values ranging from 0 to 50 μmol S•L−1. Organic S was ≤10% of total S in precipitation, 5 to 54% in throughfall, 1 to 50% in stem flow, 16 to 46% in O-horizon solution, 11 to 21% in A- or E-horizon solutions, and 0 to 29% in B-horizon solutions. Organic S was positively correlated with organic C and organic N in Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and red alder (Alnusrubra Bong.) soil solutions and in Douglas-fir stem flow (r2 = 0.68 to 0.96, p < 0.001 ). Inclusion of solution organic S in nutrient cycling budgets can alter estimates of S transfers within forests and S transport out of some forest ecosystems.
Homann, P.S., M.J. Mitchell, H. Van Miegroet, and D.W. Cole. 1990. Organic sulfur in throughfall, stemflow, and soil solutions from temperate forests. Canadian Journal of Forest Research 20: 1535-1539.