Elucidating the role of surface topography and properties for the formation and stability of soil nano- and micro-aggregates by atomic force microscopy

土壤微团聚体的形成和稳定性取决于作用在各个结构单元之间的力，从而取决于相应相邻表面的类型、尺寸和性质。虽然相互作用力是短程化学力和长程范德华力、静电力、磁偶极子力和毛细力叠加的结果，但总接触表面是尺寸、主要形状、粗糙度和大尺度不规则性的函数。利用原子力显微镜（AFM）研究了土壤微团聚体的形成过程中地形、粘附力、弹性和硬度等因素的作用，以及微团聚体在外力作用下的稳定性。将特别考虑胞外聚合物作为矿物颗粒之间的粘合剂和作为引起显著表面改变的物质的作用。目的是（i）确定和量化控制聚集体稳定性的表面性质，（ii）通过分析相互作用力和接触表面形貌来解释它们的形成和稳定性，以及（iii）将这些结果与由束伙伴获得的化学信息联系起来。由于AFM的空间分辨率，我们将提供信息的纳米到（亚）微米尺度上的尖端表面相互作用，以及“化学”力采用功能化的提示。我们的映射策略是基于一个分层的图像采集方法，其中包括逐步缩小规模的感兴趣的区域的分析。使用经典和空间统计学，将评估表面特性并实现空间模式。空间相关性将用于将AFM数据与联盟获得的化学数据相匹配。升级是基于数学粗粒度方法。

Formation and stability of soil micro-aggregates depend on the forces which are acting between the individual building blocks and in consequence on type, size and properties of the respective adjacent surfaces. While the interaction forces are the result of the superposition of short-range chemical forces and long-range van-der-Waals, electrostatic, magnetic dipole and capillary forces, the total contact surface is a function of the size, primary shape, roughness and larger-scale irregularities. By employ-ing atomic force microscopy (AFM), we will explore the role of topography, adhesion, elasticity and hardness for the formation of soil micro-aggregates and their stability against external stress. Special consideration will be put on the role of extracellular polymeric substances as glue between mineral particles and as a substance causing significant surface alteration. The objectives are to (i) identify and quantify the surface properties which control the stability of aggregates, (ii) to explain their for-mation and stability by the analysis of the interaction forces and contacting surface topography, and (iii) to link these results to the chemical information obtained by the bundle partners. Due to the spatial resolution available by AFM, we will provide information on the nano- to the (sub-)micron scale on tip-surface interactions as well as "chemical" forces employing functionalized tips. Our mapping strategy is based on a hierarchic image acquisition approach which comprises the analysis of regions-of-interest of progressively smaller scales. Using classical and spatial statistics, the surface properties will be evaluated and the spatial patterns will be achieved. Spatial correlation will be used to match the AFM data with the chemical data obtained by the consortium. Upscaling is intended based on mathe-matical coarse graining approaches.