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通过分析硫、硒、砷的固相形态和对阴离子吸附/解吸以及生物学转化等定向过程的研究,探讨了灰化森林土中硫、硒、砷的行为。研究结果表明,由于近期人为造成的酸化,已导致土壤吸附态硫明显的净积累。而B层土壤有机质中碳硫比没有相应的变化。斯堪的纳维亚北部的大部分土壤中,吸附态硫数量仅占瑞典西南部地区土壤的20-40%。有机质对阴离子吸附有一定的影响,本文对影响原因作了讨论。文中提出一个简单的模型,假定一个硫酸根离子的吸附伴随着两个氢离子吸附时,这可以很好地预测硫的吸附。在斯堪的纳维亚北部,伊毛缟石型矿物是灰化土B层中最丰富的次生矿物,也是最重要的阴离子吸附体,这些矿物可能是通过羟基铝与硅酸的反应在B层中形成的。森林土壤中硒的循环与有机质有极密切的联系。进入林地中的亚硒酸盐将很快被固定并进入腐殖物质中,或通过微生物的还原作用而挥发。大部分土壤内在硒存在于疏水腐殖质之中。与上相反,砷循环主要是砷酸根的吸附与解吸,至少在矿质土壤中是以这种方式进行的。砷的垂直再循环是微不足道的。这意味地上输入的砷对生物吸收比提高矿质土壤中砷水平重要得多。
By analyzing the solid phase morphology of sulfur, selenium and arsenic, and the orientation process of anion adsorption / desorption and biological transformation, the behavior of sulfur, selenium and arsenic in ashed soil was discussed. The results show that, due to the recent human-induced acidification, a significant net accumulation of sulfur in the soil has been caused. However, there is no corresponding change of carbon to sulfur ratio in B soil organic matter. Most of northern Scandinavia soil contains only about 20-40% of the adsorbed sulfur in the southwestern part of Sweden. Organic matter on the anion adsorption has a certain impact, the paper discussed the impact of the reasons. A simple model is proposed in this paper. Assuming that the adsorption of one sulfate ion is accompanied by the adsorption of two hydrogen ions, it is a good predictor of sulfur adsorption. In the northern part of Scandinavia, the feldspathic minerals are the most abundant secondary and most important anion adsorbents in the B layer of asbestos, probably through the reaction of hydroxy aluminum with silicic acid B layer formed. Selenium circulation in forest soils is closely related to organic matter. Selenite entering the woodlands will soon be immobilized and enter the humic substances or be volatilized by microbial reductions. Selenium is present in hydrophobic humus in most soils. In contrast, the arsenic cycle is mainly arsenate adsorption and desorption, at least in mineral soils. Vertical arsenic recycling is negligible. This means that arsenic input to the soil is much more important for bioaccumulation than increasing arsenic levels in mineral soils.