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本研究的目的是定性和定量地测定森林土壤因酸性大气沉降而导致的化学和矿物学变化。在大气酸性沉降强烈影响区(土壤pH2.8～3.0)及其非污染参照区(土壤pH5.0～6.0)采集了四个深度的土壤样品(0～5c,5～10cm,10～20cm,20～30cm),结果表明,污染区土壤发生了强度风化作用.表现为粘粒和粉粒含量升高,团聚作用下降及粘粒淀积。而且,污染区土壤表层C、S总量和重金属(Pb、Zn和Cu)含量也较高,并伴随着极低的盐基饱和度(特别是Ca、Mg的饱和度)和极高的Al饱和度(CEC的50～80%)。这些与土壤饱和水提取液分析结果相一致。此外,在污染的表土中,发现铁氧化物含量高,但无“次生”铝绿泥石存在(因为它在pH<4.0时不稳定)。与此同时,还发生了脱硅作用。强度风化作用引起粘粒层电荷损失,并产生了高膨胀性三层硅酸盐。
The purpose of this study was to qualitatively and quantitatively determine the chemical and mineralogical changes of forest soils due to acid-atmospheric deposition. Four deep soil samples (0 ~ 5c, 5 ~ 10cm, 10 ~ 20cm, 5 ~ 10cm) were collected in the area with strong acid deposition in the atmosphere (pH value of 2.8 ~ 3.0) and their non-contaminated reference area 20 ~ 30cm), the results showed that the intensity of soil weathered in the polluted area occurred in the performance of the clay and grain content increased, agglomeration decreased and clay deposition. In addition, the contents of total C, S and heavy metals (Pb, Zn and Cu) in the contaminated area were also high, accompanied by extremely low base saturation (especially Ca and Mg saturation) and extremely high Al Saturation (50-80% of CEC). These are consistent with the results of soil saturated water extract analysis. In addition, high levels of iron oxide were found in contaminated topsoil but no “secondary” aluminum chlorite was present (as it was unstable at pH <4.0). At the same time, desiliconization also took place. Intensity weathering causes charge loss in the cosmetal layer and produces a highly expansible three-layer silicate.