Three-dimensional visualization and quantification of soil macroporosity and water flow patterns using computed tomography
Three-dimensional visualization and quantification of soil macroporosity and water flow patterns using computed tomography
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DOI：
10.1079/sum2002121
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发表时间：
2002-06-01
影响因子：
3.8
通讯作者：
Mooney, SJ
中科院分区：
文献类型：
--
作者：
Mooney, SJ
土壤结构在土壤和水过程中的作用的评估工作受到基于二维几何或扰动样品的数据的限制。计算机断层扫描（CT）是一种非侵入性技术，可以对异质材料进行三维非破坏性检查。X射线CT扫描用于获取对比土壤类型的系列图像，这些图像可用于渲染，从而在三维空间中量化重要的土壤成分。通过在渗透期后重复扫描技术，还可以在真实的时间内检查水运动的性质。不同土壤类型之间的大孔隙结构是高度可变的，一般出现在检查的分辨率为不连接的孔隙段。正如预期的那样，水流特征类似于大孔隙结构，润湿模式类似于在不同土壤中确定的达西流和优先流。由此发现，在桑迪粘土中，C.与c.桑迪壤土为50%。此外，可以可视化石头和其他矿物材料的三维分布。结果表明，计算机断层扫描的好处，更传统的分析土壤结构，其潜力作为一种工具，检查动态土壤过程。然而，与可访问性、分辨率和伪影相关的问题仍然限制了该技术。
Efforts to assess the role of soil structure in soil and water processes have been limited by data based on two dimensional geometry or disturbed samples. Computed tomography (CT) is a non-invasive technique that allows for the three dimensional, non-destructive examination of heterogeneous materials. X-ray CT scanning was used to acquire serial images of contrasting soil types that could be used to render, and hence, quantify important soil constituents in three dimensions. By repeating the scanning techniques after an infiltration period, it was also possible to examine the nature of water movement in real time. Macropore architecture between different soil types was highly variable and generally appeared as unconnected pore segments at the resolution examined. As expected, water flow characteristics were similar to macropore structure, with wetting patterns resembling both Darcian and preferential flow identified in different soils. From this, it was found that in the sandy clay soil c. 90% of macropore space was active following infiltration, compared with c. 50% for the sandy loam soil. In addition, it was possible to visualize the three dimensional distribution of stones and other mineral material. The results illustrated the benefits of computed tomography over more conventional analyses of soil structure, and its potential as a tool for examining dynamic soil processes. However, problems associated with accessibility, resolution and artefacts still provide limitations of the technique.