A holistic perspective on soil architecture is needed as a key to soil functions

Abstract

Soil functions, including climate regulation and the cycling of water and nutrients, are of central importance for a number of environmental issues of great societal concern. To understand and manage these functions, it is crucial to be able to quantify the structure of soils, now increasingly referred to as their "architecture," as it constraints the physical, chemical and biological processes in soils. This quantification was traditionally approached from two different angles, one focused on aggregates of the solid phase, and the other on the pore space. The recent development of sophisticated, non-disturbing imaging techniques has led to significant progress in the description of soil architecture, in terms of both the pore space and the spatial configuration of mineral and organic materials. We now have direct access to virtually all aspects of soil

A Multivariate Approach to Evaluate Reduced Tillage Systems and Cover Crop Sustainability

“…The final RSI score evaluates the combination of tillage intensity and soil covering with an holistic approach [58]. It showed the positive effect of NT relative to conventional tillage, even in the short term.…”

Lessons from a landmark 1991 article on soil structure: distinct precedence of non-destructive assessment and benefits of fresh perspectives in soil research

“…To a large extent, the same could be said about soils: by breaking down a soil artificially into progressively smaller chunks and by subjecting them to standard stability tests, one can obtain information about how strongly bound together mineral particles are in them by various types of cementing agents, e.g., humic substances, metal or Fe/Al oxides and hydroxides, bacterial or archaeal exopolymers, or fungal hyphae. A considerable amount of instructive work has been carried out during the last decades to analyse the constituents found in "aggregates" of different sizes and to explore the interactions and binding mechanisms that are involved (see, e.g., detailed review in Totsche et al, 2018;Vogel et al, 2021). In theory, knowledge about the nature and strength of cementing agents gluing chunks of soil may help to some extent understand how resilient the soils are to environmental influences (e.g., raindrop impacts, root penetration, susceptibility to erosion).…”

“…In that general context, the primary objectives of the present article are to provide some background information on views similar to those presented by Professor Letey, which had manifested implicitly in the soil science literature prior to 1991, to analyse in detail his contribution to the debate and explain to what extent his perspective was much ahead of its time, and to outline how significant technological progress over the last two decades has helped make Letey's (1991) views increasingly implementable and relevant in practice. Since the recent article by Vogel et al (2021) provides a snapshot of the current status of the paradigm shift related to the structure/architecture of soils, the present article attempts to complement the picture by emphasizing the historical context of this shift as well as the chronology of its evolution over the last 3 decades. We also briefly discuss where the research on soil structure/architecture appears to be headed at this juncture, and what lessons can be drawn from Letey's (1991) landmark article about the practice of soil science in general.…”

Editorial: Microscale Modelling of Soil Processes: Recent Advances, Challenges, and the Path Ahead

“…Soil architecture is an essential characteristics of soils, in that it determines the geometry, topology, and connectivity of the pore space, in which a large fraction of soil processes is taking place (Letey, 1991;Vogel et al, 2021). It is therefore important that modelling efforts aim at predicting how this architecture is likely to evolve in time, under the influence of external stimuli or the processes occuring in soils.…”

“…This framework is presented from the perspective of the "aggregate" perspective on soil architecture, of which the dynamics of "microaggregate" formation is an important aspect. However, the cellular automaton method developed by Rupp et al could also potentially prove useful within the context of the holistic perspective advocated by Vogel et al (2021) dispersal to analyze the dynamic response of biodegradation as an important microbial ecosystem function to disturbance events, and systematically vary the frequency of the disturbance events, and the size and fragmentation of the disturbed area. They find that the influence of the disturbance size on functional recovery depends on the spatial fragmentation of the disturbance, indicating that to some extent disturbance size can be compensated for by the spatial configuration of the disturbed area.…”