陕南土壤中水溶态硒、氟的含量及其在生态环境的表征

CONCENTRATION AND ENVIRONMENTAL SIGNIFICANCE OF WATER SOLUBLE-Se AND WATER SOLUBLE-F IN SOILS OF SOUTH SHAANXI PROVINCE

以陕南早古生代地层上发育的土壤为材料,研究土壤中水溶态硒、氟的含量及其与总量、土壤pH值之间的关系,探讨土壤水溶态硒、氟含量在生态环境中的表征作用.结果表明,陕南土壤中水溶态硒、氟的平均含量分别为0.012μg·g-1和0.87μg·g-1,土壤中水溶态硒、氟的含量同其总量之间都存在着显著的正相关关系;在供试土壤pH范围内(5.10—7.52),水溶态硒的含量随pH值的增加先降后升,水溶态氟随pH值的增减而同步增减,其相互间的关系均可用函数方程式定量表达.水溶态硒含量能较好地表征陕南的高硒生态环境,水溶态氟可作为生态系氟质量状况的一个指标,但其指示作用又囿于地域空间的限制.

Typical soil profiles developed from early Paleozoic stratum in south Shanxi Province were selected to study the concentration of water solution-Se and water soluble-F, the relationships between them with total-Se, total-F, and soil pH as well as their significance in environment were also discussed. Results shown that the average concentrations of water soluble-Se and water soluble-F in tested soils were 0.012(μg·g^(-1)) and 0.87(μg·g^(-1)), respectively. There were significant positive correlation between water soluble-Se and total-Se, (water) soluble-F and total-F; as soils pH increased from 5.10 to 7.52, the concentration of water soluble-Se (decreased) first but followed by increased, while the concentration of water soluble-F was synchronously (increased), and those relationship could be quantificationally expressed by function equations. Results also shown that the concentration of water soluble-Se could well reflect the high level of Se environment in south Shanxi Province, whereas, once the concentration of water soluble-F was used as an indicator of environmental F quality assessment, the spatial domain must be considered.