Droplet infiltration and organic matter composition of intact crack and biopore surfaces from clay‐illuvial horizons
Droplet infiltration and organic matter composition of intact crack and biopore surfaces from clay‐illuvial horizons
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粘土沉积层完整裂缝和生物孔表面的液滴渗透和有机质组成
DOI：
10.1002/jpln.201400209
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发表时间：
2015
影响因子：
2.5
通讯作者：
中科院分区：
文献类型：
--
作者：
在结构性土壤中，生物孔壁和团聚体涂层中的有机质对活性溶质和水的吸附以及土壤基质和优先流动(PF)区域之间的溶质质量交换可能是重要的。结构表面被幻影粘土-有机材料和不同来源的OM覆盖，例如蚯蚓粪和根渣。研究的目的是验证有机质在粘粒-沉积土层(BT)中对完整结构表面的润湿性和渗透性的影响，并研究有机质组成的毫米尺度分布与水分和溶质迁移的相关性。从黄土层和冰川层制备了完整的团聚体表面和生物岩壁。利用漫反射红外傅里叶变换(DRIFT)光谱分析了OM组成在毫米尺度上的空间分布。以有机质中烷基官能团与羧基官能团的比值作为有机质的潜在润湿性指数。用接触角(CA)和水滴穿透时间(WDPT)测定了水滴和乙醇水滴的渗透动力学。在黄土-BT的蚯蚓洞穴和涂层裂缝的完整表面上，OM的潜在润湿性比未涂层的基质显著降低。这些数据对应于WDPT的增加，表明亚临界水的拒水性为毫米级。黄土层的蚯蚓洞和裂缝涂层与WDPT>； 为2.5.S，呈高度线性关系。黄土-Bt的其他表面和耕作衍生的Bt的大部分表面都没有发现排斥作用。在这些表面上，没有发现OM的潜在润湿性和表面的实际润湿性之间的关系。结果表明，如果有机质含量增加，烷基官能团含量增加，则有机质在完整表面结构上的吸水率，即PF路径与土壤基质之间的质量交换，可以局部地受到毫米级OM分布的影响。对于这类表面，势能和实际润湿性之间的关系提供了从漂移光谱扫描中评估润湿性、吸附和质量交换的毫米尺度空间分布的可能性。
The organic matter (OM) in biopore walls and aggregate coatings may be important for sorption of reactive solutes and water as well as for solute mass exchange between the soil matrix and the preferential flow (PF) domains in structured soil. Structural surfaces are coated by illuvial clay‐organic material and by OM of different origin,e.g., earthworm casts and root residues. The objectives were to verify the effect of OM on wettability and infiltration of intact structural surfaces in clay‐illuvial horizons (Bt) of Luvisols and to investigate the relevance of the mm‐scale distribution of OM composition on the water and solute transfer. Intact aggregate surfaces and biopore walls were prepared from Bt horizons of Luvisols developed from Loess and glacial till. The mm‐scale spatial distribution of OM composition was scanned using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. The ratio between alkyl and carboxyl functional groups in OM was used as potential wettability index (PWI) of the OM. The infiltration dynamics of water and ethanol droplets were determined measuring contact angles (CA) and water drop penetration times (WDPT). At intact surfaces of earthworm burrows and coated cracks of the Loess‐Bt, the potential wettability of the OM was significantly reduced compared to the uncoated matrix. These data corresponded to increased WDPT, indicating a mm‐scaled sub‐critical water repellency. The relation was highly linear for earthworm burrows and crack coatings from the Loess‐Bt with WDPT > 2.5 s. Other surfaces of the Loess‐Bt and most surfaces of the till‐derived Bt were not found to be repellent. At these surfaces, no relations between the potential wettability of the OM and the actual wettability of the surface were found. The results suggest that water absorption at intact surface structures,i.e., mass exchange between PF paths and soil matrix, can be locally affected by a mm‐scale OM distribution if OM is of increased content and is enriched in alkyl functional groups. For such surfaces, the relation between potential and actual wettability provides the possibility to evaluate the mm‐scale spatial distribution of wettability and sorption and mass exchange from DRIFT spectroscopic scanning.
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影响因子：
2.9
作者：
Kaiser, M.;Ellerbrock, R. H.;Gerke, H. H.
通讯作者：
Gerke, H. H.
影响因子：
2.8
作者：
H. Gerke
通讯作者：
H. Gerke
完整生物孔和裂缝表面有机质成分的毫米级分布
影响因子：
4.2
作者：
Ellerbrock
通讯作者：
Ellerbrock
土壤吸水率的毫米级空间变异：尺度、表面高程和亚临界排斥效应
DOI：
--
发表时间：
2004
期刊：
影响因子：
--
作者：
P. Hallett;N. Nunan;J. T. Douglas;I. Young
通讯作者：
I. Young
修正微地形对完整土壤骨料表面有机质 DRIFT 绘图信号的影响
影响因子：
2.9
作者：
M. Leue;H. Gerke;R. Ellerbrock
通讯作者：
R. Ellerbrock