Removal of short-range-order minerals prior to grain-size analysis of volcanic ash soils.
Removal of short-range-order minerals prior to grain-size analysis of volcanic ash soils.
复制标题
在对火山灰土壤进行粒度分析之前去除短程矿物。
DOI：
10.1002/jpln.201000111
复制
发表时间：
2010
影响因子：
2.5
通讯作者：
P. Kühn
中科院分区：
文献类型：
--
作者：
Andre Velescu;T. Messmer;T. Scholten;P. Kühn
在分析 Andosol 的土壤质地时，团聚体的不完全分散是一个众所周知的困难，特别是在没有新鲜土壤材料的情况下。为了促进此类研究，对来自选定的 Andosol 剖面（墨西哥南部）的富含短程有序矿物的风干样品进行了多种分散程序。因此，我们提出了一种基于草酸钾、草酸铵和草酸连续化学处理的改进方法，该方法能够可靠地去除胶结剂，并在添加焦磷酸钠后使土壤颗粒稳定分散。事实证明，该方法对于常规粒度测定具有良好的重复性和高度可靠性。由溶解原生矿物或新鲜火山玻璃的固有风险引起的潜在误差仍然远远超出了通过其他常用技术对高抗性骨料进行不完全且不可再现的分散而导致的分析误差。
Incomplete dispersion of aggregates is a well-known difficulty when analyzing soil texture of Andosols, particularly if no fresh soil material is available. To facilitate such investigations, several dispersion procedures were carried out on air-dried samples rich in short-range-order minerals, originating from selected Andosol profiles (S Mexico). As a result, we propose an improved method based on a sequential chemical treatment with K oxalate, NH4 oxalate, and oxalic acid that reliably removes cementing agents and allows for a stable dispersion of soil particles after addition of Na pyrophosphate. This method was proved to be well reproducible and highly reliable for routine grain-size determinations. The potential error caused by the inherent risk of dissolving primary minerals or fresh volcanic glass remains far beyond the analytical error resulting from the incomplete and irreproducible dispersion of highly resistant aggregates by other commonly used techniques.