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各个构件之间的作用力，从而取决于相应相邻表面的类型、大小和性质。虽然相互作用力是短程化学力和长程范德华力、静电力、磁偶极子力和毛细管力叠加的结果，但总接触表面是尺寸、初级形状、粗糙度和较大尺度不规则性的函数。通过原子力显微镜(AFM)，我们将探索地形、粘附性、弹性和硬度对土壤微团聚体形成的作用及其对外部应力的稳定性。将特别考虑胞外聚合物作为矿物颗粒之间的粘合剂和引起重大表面变化的物质的作用。目的是(I)识别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，我们将提供有关针尖-表面相互作用的纳米到(亚)微米尺度的信息，以及使用功能化尖端的“化学”力。我们的测绘策略基于分层图像获取方法，该方法包括对逐渐变小的尺度的感兴趣区域进行分析。使用经典统计和空间统计，将评估表面属性，并将获得空间图案。空间相关性将用于将AFM数据与该联盟获得的化学数据进行匹配。升级的目的是基于数学粗粒化方法。

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.