Studies on Material Cycling in Evergreen Broad-Leaved Forest Ecosystem in Hangzhou:Ⅳ.Uptake,Storage and Return of S by Vegetation

The work was carried out to study the uptake,storage and return of S in the evergreen broad-leaved forest ecosystem of Hangzhou in Zhejiang Province,based on the annuam increments of plants and Scontents per unit weight plant organs as well as the measured data about the biological return and decomposition.Results showed that the vegetation layer had an annual S uptake of 55.02kg ha^-1,which accounted for 15.8% of the total S storage in the vegetation layer,The S uptake was the highest in the arbor layer but the lowest in the shrub layer,the biological return of S was 50% higher than the biological uptake,indicating the relatively high cycling effciency of S.Nevertheless,S had a relatively low rate opf biological release,so that S trended to accumulate in the litter layer,S taken up by plants each year came mostly from precipitation and the reserve of soil.