腐殖酸结合汞对多年生植物(Citrus Sinensis L. Osbeck)的生物有效性初探

野外采集广柑树及供其生长的土壤，研究多年生植物对土壤Hg的吸收及与土壤理化性质、腐殖酸结合汞（HS—Hg）的关系。结果表明，在酸性土壤环境中，酸性过强，果树吸收Hg量会更低；果实部分Hg含量与土壤的有机质或腐殖酸含量呈现负相关关系；HS—Hg特别是FA—Hg（富啡酸结合汞）组分是果树吸收、积累Hg的重要来源，其与根Hg的相关系数达到0．700^＊-0．759^＊＊，且以表层土壤更能提供有效的HS—Hg。

Bioavailability of Humic-Substance-Bound Mercury to Perennial Plant Citrus Sinensis L. Osbeck

Citrus tree(sCitrus sinensis L. osbeck)and their supporting soils were sampled for investigation of Hg uptake by the perennial plant and its relationship to soil properties and humic-substance-bound Hg (HS-Hg) in the soil. Results showed that in acidic soil, the more acidic the soil was, the less Hg the citrus trees absorbed. Hg content in fruits was negatively correlated with the contents of organic matter or humic substances in the soils. HS-Hg, especially the FA-Hg fraction, was the major Hg source for citrus trees. Correlation coefficients between citrus root Hg and soil HS-Hg reached 0.700*~0.759**. Surface soil could provide more available HS-Hg than sub-surface soil.