SGER: The Effects of Acid Deposition on Soil Physical Properties

本研究的目的是检验专业的影响， 土壤结构酸沉降离子组分 特性. 酸沉降影响土壤的成分 溶液和成分通过土壤的迁移。 认识到土壤的化学和矿物学 通过酸沉降的转化，据推测， 改变土壤的物理性质，包括 甚至在缓冲良好的土壤中也可能使用胶结剂。 酸沉降对土壤形态和结构的影响 在两种实验室实验中检测。延长浸出 不同土壤的长柱，和土壤中含有的浸出 在较浅的平底锅中进行不同的处理，包括 润湿和干燥。 对于对照实验，两种 水泥，碳酸盐和铁铝氧化物将用于混合 天然和人工土壤。 在评估的重要性 根据土的结构、物理性质选择胶结剂 包括水力传导性，凝聚力和 将通过比较酸和酸的浓度来检查聚集体的稳定性。 和 在不同缓冲条件下的对照处理。 到 尽可能采用无损X射线、伽马射线或CT扫描 将对土壤的内部结构进行观察， 将内部结构的变化与测量的物理 特性. 因为土壤与土壤化学和水文学有关 了解它们之间的相互关系， 提高我们预测不同环境如何反应的能力 酸沉积。

The objective of this research is to examine the effect of major ion constituents arising from acid deposition on soil structural properties. Acid deposition effects the composition of the soil solution and the migration of constituents through the soil. Recognizing that the chemistry and mineralogy of soils are transformed by acid deposition, it is postulated that acidification alters physical properties of soils including the behavior of cementing agents perhaps even in well buffered soils The effects of acid deposition on soil morphology and structure will be examined in two kinds of laboratory experiments. Prolonged leaching of different soils in long columns, and leaching of soils contained in shallower pans subjected to different treatments, including wetting and drying. For controlled experiments, two kinds of cement, carbonated and iron-aluminum oxides will be used in mixed natural and artificial soils. In evaluating the importance of selected cementing agents to soil structure, physical properties of the soil including hydraulic conductivity, cohesion and aggregate stability will be examined by comparing acid and control treatments under different buffering conditions. To the extent possible, non-destructive X-ray, gamma ray or CT-scan observations of the internal structure of the soil will be made to relate changes in internal structure to measured physical properties. Because soil relates to soil chemistry and hydrologic processes, understanding the interrelation among them should improve our ability to predict how different environments respond to acid deposition.