Structure–function co‐evolution during pedogenesis—Microaggregate development and turnover in soils

Journal of Plant Nutrition and Soil Science, Journal Year: 2024, Volume and Issue: 187(1), P. 5 - 16

Published: Feb. 1, 2024

The development of soil structure and its linkage to functions have become a major research theme boosted by the increasing threat health fertility due climate land-use changes. Water retention, flow fluids, matter dispersal, habitat provision, nutrient supply, organic element storage are fundamental life-sustaining ecosystem services. It is well accepted that soil's intimately linked architecture state aggregation, void network, composition properties solid–fluid biogeochemical interfaces therein (Figure 1). Broad consensus exists develops synergistic action physical, chemical, biological processes. Inspired these insights, we see growing number activities focus on unraveling intricate interplay interdependence in search theoretical framework allows for understanding function. Substantial progress has been achieved experimental pedogenesis joint application advanced spectroscopic, microscopic, tomographic techniques, which enabled studying structure, composition, interface already at submicron scale. In line with this, modeling endeavors give feedback designs testing various scenarios serve explore factors govern co-evolution function, or challenge concepts silico, considerably improved over last decade. This special issue responds awareness importance functioning soils other natural permeable media. We compile recent achievements shed light between "from pedon" scale delineate future directions. insights obtained from fields assembled here employ combinations experimental, observational, instrumental, computational methods will certainly allow deeper pathways fascinating function during pedogenesis. There broad functions, properties, traits is, spatial arrangement organic, inorganic, biotic components build fabric soil. At what point time this establishes, including as role variety materials diversity organisms play stability intrigued science decades. desire also inspired MADSoil consortium subject team combines empirical, theoretical, numerical expertise (Totsche et al., 2018). coordinated program was streamlined along two themes understand: Within explore, aimed characterize intact artificial microaggregates suite tomographic, spectroscopic instrumental techniques employed fashion. endeavor, however, required novel sophisticated (e.g., Amelung 2023; Bucka 2019; Dultz 2018; Guhra Krause Rodionov Ritschel 2023) approaches 2021; Felde 2019). understand link functions—habitat microorganisms, retention water, carbon, cycling elements—by rigorous mechanistic approach that, again, appropriate, comprehensive, operative codes explanatory power (Guhra Ray 2017; & Totsche, Rupp Zech, Ritschel, 2022; Schweizer, 2022). built premise quality depends physicochemical heterogeneity solid-void interfaces, so-called 2010), network morphology (cf. Rabot 2018) formation originate molecular interactions compounds act aggregate-forming composite building units Based suppositions, set hypotheses formation, stability, microscale were devised: Formation microaggregates. Aggregate follows deterministic patterns, reflected microaggregate-forming materials. Minerals like iron oxyhydroxides, phyllosilicate clay minerals, plant microbial residues nuclei Stability accumulation type increases amount pedogenic oxides fine Loss causes destabilization disintegration aggregates, release microaggregates, units, materials, then prone transport reaggregation. Functions Soil develop mineral controls turnover rate associated minerals. complexity microaggregate provides different ecological niches support diversity. community differ composition. These approached effort combined competences scientific disciplines, chemistry, mineralogy, physical microbiology, physics, data sciences, modeling. Recent outcomes be presented response three-dimensional build-up, called architecture, media microscale. MADSoil's comprised observational studies. closely investigations based simulations our observations aiming numerically 2). To separation investigation collected topsoil well-studied field sites Scheyern, Bavaria, Rotthalmünster. For studies, chose provided gradients contents minerals matter. included an optimization harmonization step optimize protocol analysis. With toposequence study, targeted (Biesgen 2020; 2018, Schweizer 2021). studies accompanied dedicated multi-stable-isotope labeling experiment, full consortium, able follow aggregation processes gluing agents inorganic cementing without presence roots (Amelung 2023). experiment 57Fe-labeled iron-oxihydroxide, 29Si-labeled 13C-labeled extracellular polymeric substances, 15N-labeled bacterial strain. depletion trial, their (composite) loss explored. Dedicated experiments focused (SOM) mechanical (Roosch 2024, issue; Siebers issue) impacts carbon (SOC) across rock fragment gradient (Schweizer issue). A series aggregate under conditions diverse typical temperate 2019, 2019) conducted. complemented Lehmann Pronk 2012; 2023): dynamic relocation explored against stress conditions, nuclei-framing examined disturbance 2024 [this issue]). Realizing advancement designs, analytical methods, sample preparation harmonized protocols multidisciplinary analysis Microaggregates commonly found part linings, crusts, embedded macroaggregates even larger aggregated structures frequently hierarchical organization. Thus, separating challenging delicate effort. comparative reasons published results, established wet fractions (Krause 2018), common isolate However, sieving known producing fractions, particular when sonication. example, cells removed surfaces uncontrolled manner, thereby precluding exploration original biogeography, thus relation (Bach mind, alternative dry developed, crushing load frame followed (Felde spectro-microscopic issue), becomes visible evolves complex bound aggregates Organo–mineral associations, small blocks studied. Aggregation up size rather rapid process (hours–weeks), mechanisms chronological order 2023), interrelated pedogenetic depending (Kögel-Knabner Amelung, arranged heterogeneous, random systematic organized pattern (Lehndorff Meyer Organic seems accumulate eventually patchy piled-up (Schweizer, Steffens 2017). variability involved build-up increased exhibiting hierarchy organo–mineral associations smallest compound 3). Various homo- und heteronucleation suspensions (Dultz identified (Bucka origin initiate accelerate resulted mineral, no nucleus. content clay-sized influences distribution stored occluded particulate (POM; Tang water related Fe-speciation (Siebers contrasting texture, al. (2024, studied using They dissolved caused water-stable shifted toward sizes. very low depended mainly but did not show strong correlation type. corresponds findings dry-separated soil, where higher SOC went difference strength samples compared cropped site, showed decrease post-modern 14C, Roosch pore connectivity contributed observed more concentrated effect decreasing both mineral-associated POM coarse fragments. further investigated laser ablation-isotope ratio mass spectrometry (Rodionov Sosa 2021), analyze decadal scales. could C reduced 58 years bulk 105 mean residence free agricultural (Rotthalmünster, Germany). only <5% micro-size fraction aggregated. abundance prokaryotic communities inhabiting responded differences matter, indicating strategists (Yao populations degraded POM, biomass contributes necromass promoting first step, while necromass-degrading bacteria role, likewise produce contribute aggregation. mixture decomposed fresh substances origin. includes exudates, lysis products, metabolites litter faunal tissues, biopolymers excreted from, roots, earthworms. numerous ways 2022), forming favoring inhibiting (Freitas 2015; Sheng 2016). might screening surfaces, agent, mediating particle (im-)mobilization (Flynn Pen 2015). Despite earthworms transfer into bioturbation mucus excretion (Brown 2000; Frelich Lavelle Stolze Szlavecz control earthworm constituents recently illuminated mucus–mineral narrow carbon/phosphorus carbon/nitrogen ratios, underpinning nutrients. activity results (re-)arrangement incorporation permeation intestinal cutaneous mucus. casts, linings burrow walls form consequence bioturbation. Considering high translocation nutrients down subsoils, attention should paid contribution biogenic polymer mixtures matterproperties. Over beyond, empirical relationship earthworms, dynamics predict structural compositional pedon impressive shapes initial stages host weathering maturation distinct horizons. dissolution neoformation, OM decomposition, metabolization stabilization, structuring, dispersion, colonization spread, unexplored many areas still awaits understanding. promising way illuminate nontrivial interdependencies empirically offered pedogenesis, representation tailored controlled boundary Hemkemeyer 2014; Münch 2002; 2012). (2023) time-lapse irrigating columns cumulative precipitation represented rainfall multiple conditions. way, authors spread total mobile inventory (Lehmann 2021) induced choosing limestone substrate weathering. features secondary released texture OC incubation soils. all variants. most pronounced clay-rich soils, having activity, independent texture. observation fosters how develop. Collaborative comprising scientists varying experience data-model integration struggle efficient quantitative framework, model. models, essential tools test silico derive causal dependencies settings, large big datasets variables mutually coupled multitude nonlinear, time-dependent relations. environmental sciences science, such models ideally integrate levels conceptual realized within approaches. guarantee make use theories farthest extent, devised supervised model collaborative interdisciplinary groups 4). aims comprehensible theories. model-data integration, web-based database binary objects (big data) needs comprise completeness produced data, (observational lab trials studies) (model runs, scenario simulation, sensitivity analysis, projections). ensures parametrization simulation parameters directly core moderated directed group involving whole consortium. formulation processes, interactions, rates, manners, mirror, anneal, confront individual researchers "semantic level." must seen crucial ongoing task. Confronting iterative refinement ("level evidence"). appropriate physics collecting developing laws reproduce reactions interactions. Hence, substantiation rates "natural laws," principles. Casting principles mathematical (Ray coding algorithms programs final steps bits bytes"). Successful presented, (2019), (2021), Zech (2020) entangled particularly expresses aggregates. necessitates assessment habitats (Van Leeuwen 2019), determines elements, retains channels fluids. combination regarding transport, attachment, re-arrangement reveal shaped emerge transition scales (Pot Roose Early (Crawford 1997, 2012) introduced self-organization cellular automaton setting binding key drivers (representing chemical bonds bindings products fungi). approaches, (2017) (2018) developed comprehensive toolbox simulate spatially temporally explicit complement discrete method rearrangement continuous partial differential equation fluids solutes. By specific it possible identify evolution establishment stationary structure. Complementarily, Totsche (2019) prototypical quartz, illite, goethite) diffusively displaced walk until they merge upon contact once Derjaguin-Landau-Verwey-Overbeek (DLVO)-type energy barrier overcome. physically allowed reconstructing milieu geometry 5). (2021) extended include gravity decisive mechanism settling particles and, therefore, fractionation accumulation. can decelerate among others relative velocity aqueous density size. Adopting prototypes approach, size, shape, formed. degree shielded oppositely charged main governs if favored hindered. Later, impact aspect ratio, surface charge, mixing heteroaggregation edge-to-edge edge-to-face card-house resemble those experiments. Building (2022) hydrolysis unsaturated, heterogeneous CO2 output. Finally, combining previous attempts simultaneous formation/disaggregation (Zech, revealed primed decomposition native addition 6). Last, exemplified continuum-scale pore-scale limitations diffusive oxygen availability, texture-dependent occlusion, determined production storage. Throughout applied tool subtle synergism inherent E-science, capital E referring "enhanced," describes paradigm forcefully consistently utilizes digital infrastructure aspects. E-science integrates resources concepts, tools. means questions organize capacities generating, analyzing, curating FAIR (i.e., findable, accessible, interoperable, reusable) publication results. observation, correlative increasingly finer spatiotemporal detail spectro-microscopy tomography multi-omics), disciplines generate operate Big Data, enormous rapidly state, development, acquisition, collection, storage, processing, curation information meta-analysis. operating Data unearthing hidden information, uncovering correlations, or, generally, analyzing relations patterns. objectives realm data-driven intelligence (AI), neural networks, machine learning, deep learning. If research, targeting generation structure–function relationships scenario-based projections ("digital twins"), drawing inferences management, rigorously biological, laws. Such intrinsically explanatory, logic reproducible, generated intelligible, decisions made traceable. Of course, informed populated wealth harbored available science. hand, answer "why" "how": Why result? How reached? Future efforts AI-based invest comprehensible-explanatory big-data inform algorithms. Soils vulnerable thin subsurface ecosystems. alter exchange energy, controlling phreatic zone groundwater. Assessing transformative metabolic ecosystems services provide sustain life. An unprecedented forward generating respect processing multi-omics, metagenomics, proteomics, metabolomics. aligning omics in-depth fingerprinting immobile insight hand. characterization actual activities, connected cycles identified. fluid fluxes domains life viruses, communities, interplay, proximate Climate changes affecting renewable manner. fertility, groundwater recharge quality, biodiversity, sequestration, cycling, production, mature increase temperature altered seasonal share, type, intensity precipitation, five governing constantly change. addition, alien floral species, wanted unwanted, migrate invade consequence, competition, ecology shifts, species extrusion, extinction. Effects microbiome degradative consequences greenhouse gas emission, retention. systems, micro-structured store retain extreme habitats, harbor Functional redundancy external finally Management strategies service protection restoration, change attenuation adaptation, aim conservation, amelioration Linchpin thorough effects land micron landscape So far, discussion relate confronted perspectives Vogel Yudina Kuzyakov, 2019): solid-phase perspective pore-phase perspective. one alleged conceive solids, primary ("solid phase perspective"). conceives voids pores, framed solid particles. Both "hierarchy" constitutive feature conceived complementary aspects Indeed, review, refer "soil solids considering (surface)." Ignoring topography, ignore exposed space particles, (micro-)aggregates, phases hyphae. habitat, so forth, governed variable topography emerging interface. anneal extent basis PIs Wulf Georg Guggenberger, Klaus Kaiser, Claudia Knief, Erwin Klumpp, Ingrid Kögel-Knabner, Eva Lehndorff, Robert Mikutta, Stephan Peth, Alexander Prechtl, Nadja Ray, Nina Siebers, Daniel Uteau, Bei Wu, Kai Totsche; postdoctoral Michaela Aehnelt, Stefan Dultz, Vincent Felde, Nele Meyer, Andrey Rodionov, Steffen Susanne Woche; PhDs Franziska Bucka, Danh Biesgen, Fechner, Tom Guhra, Jacqueline Kaldun, Lars Krause, Svenja Roosch, Andreas Rupp, Ni Tang, Tongyan Yao, Simon deeply acknowledged fruitful inspiring cooperation than 7 Research Unit MAD Soil—Microaggregates: (DFG RU 2179). highly appreciate financial Deutsche Forschungsgemeinschaft (Contract No 251268514) thankful continued Patricia Schmitz-Möller her DFG. Very thanks go Aehnelt least constructive engagement coordination unit. Thomas his constant endorsement Ina Voigt enthusiastic assistance sharing applicable article, analyzed current study.

Language: Английский

Aggregates versus pores – is the soil science community torn apart? A survey

Journal of Plant Nutrition and Soil Science, Journal Year: 2024, Volume and Issue: 187(2), P. 171 - 176

Published: March 10, 2024

Abstract Whether soil structure should be viewed mostly as a system of pores or set aggregates is question scientists keep debating in the literature, but it unclear whether wider science community also divided. In quick survey among mainly German all career levels and sub‐disciplines, most participants agreed that both are important to describe structure. The debate can nevertheless fruitful if led more efficiently, avoiding generalisations, misunderstandings potential emotional barriers.

Language: Английский

Lime and gypsum reduce N-fertilizer requirements and improve soil physics, fertility and crop yields in a double-cropped system

Geoderma, Journal Year: 2024, Volume and Issue: 453, P. 117132 - 117132

Published: Dec. 7, 2024

Language: Английский