Soil pore system evaluated from gas measurements andCTimages: A conceptual study using artificial, natural and3D-printed soil cores
Soil pore system evaluated from gas measurements andCTimages: A conceptual study using artificial, natural and3D-printed soil cores
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DOI：
10.1111/ejss.12999
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发表时间：
2020-06-28
影响因子：
4.2
通讯作者：
Morari, Francesco
中科院分区：
文献类型：
--
作者：
Lamande, Mathieu;Schjonning, Per;Morari, Francesco
结合数字成像，物理模型和实验室测量是更好地理解土壤孔隙系统和土壤功能之间的复杂关系的又一步。在耕作的水耕淋溶土中，从表土和底土中采集了8个100 cm（3）的天然土芯，我们假设它们具有对比的孔隙系统。人造100-cm（3）岩心由塑料或高压蒸汽加气混凝土（AAC）制成。为塑料圆柱体和两个AAC圆柱体中的一个圆柱体钻八个每个直径（1.5和3 mm）的垂直孔。所有天然和人造核都在X射线CT扫描仪中扫描并以3D打印。在所有岩心上测量了有效充气孔隙度、真实达西空气渗透率、压力梯度为5 hPa时的表观空气渗透率和氧气扩散。活性孔隙系统的特点不同的表土（海绵状，类似大小的大孔隙网络）和底土（占主导地位的大型垂直大孔隙）。在简化的孔隙网络上测量的活性土壤孔隙特性，即从人工和打印的土芯中，支持在顶部和底土之间观察到的对流和扩散的空气输送的根本差异。研究结果证实了将土壤孔隙系统划分为干孔隙、边缘孔隙和远孔的概念模型用于描述土壤结构对气体运移影响的适用性。这项研究表明，使用3D打印土芯重建土壤大孔隙网络以更好地了解土壤孔隙功能的潜力很大。
Combining digital imaging, physical models and laboratory measurements is a step further towards a better understanding of the complex relationships between the soil pore system and soil functions. Eight natural 100-cm(3)soil cores were sampled in a cultivated Stagnic Luvisol from the topsoil and subsoil, which we assumed had contrasting pore systems. Artificial 100-cm(3)cores were produced from plastic or from autoclaved aerated concrete (AAC). Eight vertical holes of each diameter (1.5 and 3 mm) were drilled for the plastic cylinder and for one of the two AAC cylinders. All natural and artificial cores were scanned in an X-ray CT scanner and printed in 3D. Effective air-filled porosity, true Darcian air permeability, apparent air permeability at a pressure gradient of 5 hPa and oxygen diffusion were measured on all cores. The active pore system characteristics differed between topsoil (sponge-like, network of macropores of similar size) and subsoil (dominated by large vertical macropores). Active soil pore characteristics measured on a simplified pore network, that is, from artificial and printed soil cores, supported the fundamental differences in air transport by convection and diffusion observed between top- and subsoil. The results confirm the suitability of using the conceptual model that partitions the pore system into arterial, marginal and remote pores to describe effects of soil structure on gas transport. This study showed the high potential of using 3D-printed soil cores to reconstruct the soil macropore network for a better understanding of soil pore functions.