Articles | Volume 6, issue 2
https://doi.org/10.5194/soil-6-597-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-6-597-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Original research article
| Highlight paper
| 
07 Dec 2020
Original research article | Highlight paper |
| 07 Dec 2020
| 07 Dec 2020
Iron and aluminum association with microbially processed organic matter via meso-density aggregate formation across soils: organo-metallic glue hypothesis
National Agriculture and Food Research Organization, Institute for
Agro-Environmental Sciences, 3-1-3 Kan-nondai, Tsukuba, Ibaraki, 305-8604,
Japan
Masako Kajiura
National Agriculture and Food Research Organization, Institute for
Agro-Environmental Sciences, 3-1-3 Kan-nondai, Tsukuba, Ibaraki, 305-8604,
Japan
Maki Asano
Faculty of Life and Environmental Sciences, University of Tsukuba,
1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
Related authors
Kaori Matsuoka, Jo Jinno, Hiroaki Shimada, Emi Matsumura, Ryo Shingubara, and Rota Wagai
EGUsphere, https://doi.org/10.5194/egusphere-2025-2840, https://doi.org/10.5194/egusphere-2025-2840, 2025
This preprint is open for discussion and under review for SOIL (SOIL).
Short summary
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The organo-mineral assemblage formation from the mixture of crushed rocks and leaf compost was promoted by (i) microbial re-working of OM (indicated by lower C:N and higher δ13C and δ15N compared to the original leaf compost) and (ii) the supply of extractable metals (esp. oxalate-extractable Fe phase) from the rock weathering. These findings supported the organo-metallic glue hypothesis (Wagai et al., 2020) and suggest that C accretion during early pedogenesis.
Corey R. Lawrence, Jeffrey Beem-Miller, Alison M. Hoyt, Grey Monroe, Carlos A. Sierra, Shane Stoner, Katherine Heckman, Joseph C. Blankinship, Susan E. Crow, Gavin McNicol, Susan Trumbore, Paul A. Levine, Olga Vindušková, Katherine Todd-Brown, Craig Rasmussen, Caitlin E. Hicks Pries, Christina Schädel, Karis McFarlane, Sebastian Doetterl, Christine Hatté, Yujie He, Claire Treat, Jennifer W. Harden, Margaret S. Torn, Cristian Estop-Aragonés, Asmeret Asefaw Berhe, Marco Keiluweit, Ágatha Della Rosa Kuhnen, Erika Marin-Spiotta, Alain F. Plante, Aaron Thompson, Zheng Shi, Joshua P. Schimel, Lydia J. S. Vaughn, Sophie F. von Fromm, and Rota Wagai
Earth Syst. Sci. Data, 12, 61–76, https://doi.org/10.5194/essd-12-61-2020, https://doi.org/10.5194/essd-12-61-2020, 2020
Short summary
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The International Soil Radiocarbon Database (ISRaD) is an an open-source archive of soil data focused on datasets including radiocarbon measurements. ISRaD includes data from bulk or
whole soils, distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods, samples of soil gas or water collected interstitially from within an intact soil profile, CO2 gas isolated from laboratory soil incubations, and fluxes collected in situ from a soil surface.
Ryosuke Nakamura, Hidehiro Ishizawa, Rota Wagai, Shizuo Suzuki, Kanehiro Kitayama, and Kaoru Kitajima
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-447, https://doi.org/10.5194/bg-2018-447, 2018
Preprint withdrawn
Short summary
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Silicon (Si) accumulation by plants should affect biogeochemical cycling of Si, but its geographical patterns are unknown for tropical forests. Comparing forests from 700–3100 m a.s.l. on Mt. Kinabalu, we demonstrate for the first time that lowland forests include more trees with high Si concentrations and have greater annual Si flux via leaf litter, regardless of the bedrock types. Our data of 71 tree species strongly suggest the importance of plant traits in modulating ecosystem Si cycling.
Kaori Matsuoka, Jo Jinno, Hiroaki Shimada, Emi Matsumura, Ryo Shingubara, and Rota Wagai
EGUsphere, https://doi.org/10.5194/egusphere-2025-2840, https://doi.org/10.5194/egusphere-2025-2840, 2025
This preprint is open for discussion and under review for SOIL (SOIL).
Short summary
Short summary
The organo-mineral assemblage formation from the mixture of crushed rocks and leaf compost was promoted by (i) microbial re-working of OM (indicated by lower C:N and higher δ13C and δ15N compared to the original leaf compost) and (ii) the supply of extractable metals (esp. oxalate-extractable Fe phase) from the rock weathering. These findings supported the organo-metallic glue hypothesis (Wagai et al., 2020) and suggest that C accretion during early pedogenesis.
Yike Wang, Asano Maki, Qi Jiang, and Kenji Tamura
EGUsphere, https://doi.org/10.5194/egusphere-2022-728, https://doi.org/10.5194/egusphere-2022-728, 2022
Preprint archived
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The feasibility of REOs as effective tracers for Andisols aggregate dynamics was estimated from (1) the impact of the labeling processes on soil organic matters, and (2) the ability of REOs to track Andisol aggregates turnover. In this study, REOs were also applied to quantify the relationship between aggregates and soil organic carbon dynamics. Overall, this approach provides considerable opportunity for further studies to explore the interaction between C and aggregate dynamics in Andisols.
Corey R. Lawrence, Jeffrey Beem-Miller, Alison M. Hoyt, Grey Monroe, Carlos A. Sierra, Shane Stoner, Katherine Heckman, Joseph C. Blankinship, Susan E. Crow, Gavin McNicol, Susan Trumbore, Paul A. Levine, Olga Vindušková, Katherine Todd-Brown, Craig Rasmussen, Caitlin E. Hicks Pries, Christina Schädel, Karis McFarlane, Sebastian Doetterl, Christine Hatté, Yujie He, Claire Treat, Jennifer W. Harden, Margaret S. Torn, Cristian Estop-Aragonés, Asmeret Asefaw Berhe, Marco Keiluweit, Ágatha Della Rosa Kuhnen, Erika Marin-Spiotta, Alain F. Plante, Aaron Thompson, Zheng Shi, Joshua P. Schimel, Lydia J. S. Vaughn, Sophie F. von Fromm, and Rota Wagai
Earth Syst. Sci. Data, 12, 61–76, https://doi.org/10.5194/essd-12-61-2020, https://doi.org/10.5194/essd-12-61-2020, 2020
Short summary
Short summary
The International Soil Radiocarbon Database (ISRaD) is an an open-source archive of soil data focused on datasets including radiocarbon measurements. ISRaD includes data from bulk or
whole soils, distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods, samples of soil gas or water collected interstitially from within an intact soil profile, CO2 gas isolated from laboratory soil incubations, and fluxes collected in situ from a soil surface.
Ryosuke Nakamura, Hidehiro Ishizawa, Rota Wagai, Shizuo Suzuki, Kanehiro Kitayama, and Kaoru Kitajima
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-447, https://doi.org/10.5194/bg-2018-447, 2018
Preprint withdrawn
Short summary
Short summary
Silicon (Si) accumulation by plants should affect biogeochemical cycling of Si, but its geographical patterns are unknown for tropical forests. Comparing forests from 700–3100 m a.s.l. on Mt. Kinabalu, we demonstrate for the first time that lowland forests include more trees with high Si concentrations and have greater annual Si flux via leaf litter, regardless of the bedrock types. Our data of 71 tree species strongly suggest the importance of plant traits in modulating ecosystem Si cycling.
Related subject area
Soils and biogeochemical cycling
Methane oxidation potential of soils in a rubber plantation in Thailand affected by fertilization
Isotopic exchangeability reveals that soil phosphate is mobilised by carboxylate anions, whereas acidification had the reverse effect
Calcium is associated with specific soil organic carbon decomposition products
Gradual drying of permafrost peat decreases carbon dioxide production in drier peat plateaus but not in wetter fens and bogs
Effects of nitrogen and phosphorus amendments on CO2 and CH4 production in peat soils of Scotty Creek, Northwest Territories: potential considerations for wildfire and permafrost thaw impacts on peatland carbon exchanges
Aeration and mineral composition of soil determine microbial CUE
Spatial and temporal heterogeneity of soil respiration in a bare-soil Mediterranean olive grove
Depth dependence of soil organic carbon additional storage capacity in different soil types by the 2050 target for carbon neutrality
Biochar reduces early-stage mineralization rates of plant residues more in coarse-textured soils than in fine-textured soils – an artificial-soil approach
Soil organic carbon mineralization is controlled by the application dose of exogenous organic matter
Effect of colloidal particle size on physicochemical properties and aggregation behaviors of two alkaline soils
Comprehensive increase in CO2 release by drying–rewetting cycles among Japanese forests and pastureland soils and exploring predictors of increasing magnitude
Mixed Signals: interpreting mixing patterns of different soil bioturbation processes through luminescence and numerical modelling
Interactions of fertilisation and crop productivity in soil nitrogen cycle microbiome and gas emissions
Freeze–thaw processes correspond to the protection–loss of soil organic carbon through regulating pore structure of aggregates in alpine ecosystems
Soil organic matter interactions along the elevation gradient of the James Ross Island (Antarctica)
Investigating the complementarity of thermal and physical soil organic carbon fractions
Cultivation reduces quantities of mineral-organic associations in the form of amorphous coprecipitates
An ensemble estimate of Australian soil organic carbon using machine learning and process-based modelling
What is the stability of additional organic carbon stored thanks to alternative cropping systems and organic waste product application? A multi-method evaluation
Improving measurements of microbial growth, death, and turnover by accounting for extracellular DNA in soils
The influence of land use and management on the behaviour and persistence of soil organic carbon in a subtropical Ferralsol
Dissolved carbon flow to particulate organic carbon enhances soil carbon sequestration
Shifts in controls and abundance of particulate and mineral-associated organic matter fractions among subfield yield stability zones
The six rights of how and when to test for soil C saturation
Cover crops improve soil structure and change organic carbon distribution in macroaggregate fractions
Soil carbon, nitrogen, and phosphorus storage in juniper–oak savanna: role of vegetation and geology
Organic matters, but inorganic matters too: column examination of elevated mercury sorption on low organic matter aquifer material using concentrations and stable isotope ratios
Contrasting potential for biological N2 fixation at three polluted central European Sphagnum peat bogs: combining the 15N2-tracer and natural-abundance isotope approaches
Soil organic carbon stocks did not change after 130 years of afforestation on a former Swiss Alpine pasture
Land inclination controls CO2 and N2O fluxes, but not CH4 uptake, in a temperate upland forest soil
Tropical Andosol organic carbon quality and degradability in relation to soil geochemistry as affected by land use
Elemental stoichiometry and Rock-Eval® thermal stability of organic matter in French topsoils
Oil-palm management alters the spatial distribution of amorphous silica and mobile silicon in topsoils
Semantics about soil organic carbon storage: DATA4C+, a comprehensive thesaurus and classification of management practices in agriculture and forestry
Forest liming in the face of climate change: the implications of restorative liming for soil organic carbon in mature German forests
Biotic factors dominantly determine soil inorganic carbon stock across Tibetan alpine grasslands
Effects of returning corn straw and fermented corn straw to fields on the soil organic carbon pools and humus composition
Soil nutrient contents and stoichiometry within aggregate size classes varied with tea plantation age and soil depth in southern Guangxi in China
Land use impact on carbon mineralization in well aerated soils is mainly explained by variations of particulate organic matter rather than of soil structure
Inclusion of biochar in a C dynamics model based on observations from an 8-year field experiment
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Transformation of n-alkanes from plant to soil: a review
Heterotrophic soil respiration and carbon cycling in geochemically distinct African tropical forest soils
Soil organic carbon mobility in equatorial podzols: soil column experiments
Microbial activity responses to water stress in agricultural soils from simple and complex crop rotations
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Geogenic organic carbon in terrestrial sediments and its contribution to total soil carbon
Aluminous clay and pedogenic Fe oxides modulate aggregation and related carbon contents in soils of the humid tropics
Jun Murase, Kannika Sajjaphan, Chatprawee Dechjiraratthanasiri, Ornuma Duangngam, Rawiwan Chotiphan, Wutthida Rattanapichai, Wakana Azuma, Makoto Shibata, Poonpipope Kasemsap, and Daniel Epron
SOIL, 11, 457–466, https://doi.org/10.5194/soil-11-457-2025, https://doi.org/10.5194/soil-11-457-2025, 2025
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Tropical forest soils are vital for methane uptake, but deforestation and agriculture can alter soil methane oxidation. An experiment in Thailand shows that fertilization significantly suppresses methane oxidation in rubber plantation soils, affecting depths up to 60 cm. Without fertilization, deeper soil layers (below 10 cm) actively oxidize methane. These findings suggest that fertilization negatively impacts the methane uptake capacity of deep-layer soils in rubber plantations.
Siobhan Staunton and Chiara Pistocchi
SOIL, 11, 389–394, https://doi.org/10.5194/soil-11-389-2025, https://doi.org/10.5194/soil-11-389-2025, 2025
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Mineral phosphate is a finite resource, so ways must be found to optimise the use of native soil P. We have used isotopic dilution to assess how acidification and the addition of citrate or oxalate modify the lability of soil P in four contrasting soils from the Mediterranean region. Acidification did not mobilise soil P, whereas both carboxylate anions promoted soil-P lability. This suggests that soil amendments and the choice of crops that exude carboxylates could optimise P nutrition.
Mike C. Rowley, Jasquelin Pena, Matthew A. Marcus, Rachel Porras, Elaine Pegoraro, Cyrill Zosso, Nicholas O. E. Ofiti, Guido L. B. Wiesenberg, Michael W. I. Schmidt, Margaret S. Torn, and Peter S. Nico
SOIL, 11, 381–388, https://doi.org/10.5194/soil-11-381-2025, https://doi.org/10.5194/soil-11-381-2025, 2025
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This study shows that calcium (Ca) preserves soil organic carbon (SOC) in acidic soils, challenging beliefs that their interactions were limited to near-neutral or alkaline soils. Using spectromicroscopy, we found that Ca was co-located with a specific fraction of carbon, rich in aromatic and phenolic groups. This association was disrupted when Ca was removed but was reformed during decomposition with added Ca. Overall, this suggests that Ca amendments could enhance SOC stability.
Aelis Spiller, Cynthia M. Kallenbach, Melanie S. Burnett, David Olefeldt, Christopher Schulze, Roxane Maranger, and Peter M. J. Douglas
SOIL, 11, 371–379, https://doi.org/10.5194/soil-11-371-2025, https://doi.org/10.5194/soil-11-371-2025, 2025
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Permafrost peatlands are large reservoirs of carbon. As frozen permafrost thaws, drier peat moisture conditions can arise, affecting the microbial production of climate-warming greenhouse gases like CO2 and N2O. Our study suggests that future peat CO2 and N2O production depends on whether drier peat plateaus thaw into wetter fens or bogs and on their diverging responses of peat respiration to more moisture-limited conditions.
Eunji Byun, Fereidoun Rezanezhad, Stephanie Slowinski, Christina Lam, Saraswati Bhusal, Stephanie Wright, William L. Quinton, Kara L. Webster, and Philippe Van Cappellen
SOIL, 11, 309–321, https://doi.org/10.5194/soil-11-309-2025, https://doi.org/10.5194/soil-11-309-2025, 2025
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To investigate how added nutrient nitrogen (N) and phosphorus (P) affect subarctic peatlands, we sampled peat soils from bog and fen type peatlands in the Northwest Territories, Canada, and measured CO2 and CH4 production rates by means of laboratory incubations. Our short-term experiments show that changes in nutrient concentrations in soil water can significantly affect microbial carbon cycling, suggesting the necessity of additional considerations of wildfire and permafrost thaw impacts on peatland carbon storage.
Jolanta Niedźwiecka, Roey Angel, Petr Čapek, Ana Catalina Lara, Stanislav Jabinski, Travis B. Meador, and Hana Šantrůčková
EGUsphere, https://doi.org/10.5194/egusphere-2025-481, https://doi.org/10.5194/egusphere-2025-481, 2025
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Studies on how microbes use C in soils typically assume oxic conditions, but often overlook anaerobic processes and extracellular metabolite release. We examined how O2 and Fe content affect C mineralisation in forest soils by tracking 13C flow into biomass, CO2, metabolites and the active microbes under oxic and anoxic conditions. Results showed that anoxic conditions preserved C longer, especially in the high-Fe soils. We conclude that microbial exudates play a role in anoxic C stabilisation.
Sergio Aranda-Barranco, Penélope Serrano-Ortiz, Andrew S. Kowalski, and Enrique P. Sánchez-Cañete
SOIL, 11, 213–232, https://doi.org/10.5194/soil-11-213-2025, https://doi.org/10.5194/soil-11-213-2025, 2025
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This study investigated soil respiration and the main factors involved in a semi-arid environment (olive grove). For this purpose, 1 year's worth of automatic multi-chamber measurements was used, accompanied by ecosystem respiration data obtained using the eddy covariance technique. The soil respiration annual balance, Q10 parameter, rain pulses, and spatial and temporal variability of soil respiration are presented in this paper.
Clémentine Chirol, Geoffroy Séré, Paul-Olivier Redon, Claire Chenu, and Delphine Derrien
SOIL, 11, 149–174, https://doi.org/10.5194/soil-11-149-2025, https://doi.org/10.5194/soil-11-149-2025, 2025
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This work maps both current soil organic carbon (SOC) stocks and the SOC that can be realistically added to soils over 25 years under a scenario of management strategies promoting plant productivity. We consider how soil type influences current and maximum SOC stocks regionally. Over 25 years, land use and management have the strongest influence on SOC accrual, but certain soil types have disproportionate SOC stocks at depths that need to be preserved.
Thiago M. Inagaki, Simon Weldon, Franziska B. Bucka, Eva Farkas, and Daniel P. Rasse
SOIL, 11, 141–147, https://doi.org/10.5194/soil-11-141-2025, https://doi.org/10.5194/soil-11-141-2025, 2025
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Here, we investigated how biochar, a potential C sequestration tool, affects early carbon storage in different soils. We created artificial soils to isolate the impact of soil texture. We found that biochar significantly reduces plant residue’s breakdown in all soil textures but mainly in sandy soils, which naturally hold less carbon. This suggests that biochar could be a valuable tool for improving soil health, especially in sandy soils.
Orly Mendoza, Stefaan De Neve, Heleen Deroo, Haichao Li, Astrid Françoys, and Steven Sleutel
SOIL, 11, 105–119, https://doi.org/10.5194/soil-11-105-2025, https://doi.org/10.5194/soil-11-105-2025, 2025
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Farmers frequently apply fresh organic matter such as crop residues to soil to boost its carbon content. Yet, one burning question remains: does the quantity of applied organic matter affect its decomposition and that of native soil organic matter? Our experiment suggests that smaller application doses might deplete soil organic matter more rapidly, at least in coarser-textured soil. In contrast, applying intermediate or high doses might be a promising strategy for maintaining it.
Yuyang Yan, Xinran Zhang, Chenyang Xu, Junjun Liu, Feinan Hu, and Zengchao Geng
SOIL, 11, 85–94, https://doi.org/10.5194/soil-11-85-2025, https://doi.org/10.5194/soil-11-85-2025, 2025
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The differences in organic matter contents and clay mineralogy are the fundamental reasons for the differences in colloidal suspension stability behind the size effects of Anthrosol and Calcisol colloids. The present study revealed the size effects of two alkaline soil colloids on carbon content, clay minerals, surface properties and suspension stability, emphasizing that soil nanoparticles are prone to be more stably dispersed instead of being aggregated.
Yuri Suzuki, Syuntaro Hiradate, Jun Koarashi, Mariko Atarashi-Andoh, Takumi Yomogida, Yuki Kanda, and Hirohiko Nagano
SOIL, 11, 35–49, https://doi.org/10.5194/soil-11-35-2025, https://doi.org/10.5194/soil-11-35-2025, 2025
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We incubated 10 Japanese soils to study CO2 release under drying–rewetting cycles (DWCs). CO2 release was increased by DWCs among all soils, showing soil-by-soil variations in CO2 release increase magnitude. The organo-Al complex was the primary predictor for the increase magnitude, suggesting vulnerability of carbon protection by reactive minerals against DWCs. Microbial biomass decrease by DWCs was also suggested, although its link with the CO2 release increase is still unclear.
W. Marijn van der Meij, Svenja Riedesel, and Tony Reimann
SOIL, 11, 51–66, https://doi.org/10.5194/soil-11-51-2025, https://doi.org/10.5194/soil-11-51-2025, 2025
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Soil mixing (bioturbation) plays a key role in soil functions, but the underlying processes are poorly understood and difficult to quantify. In this study, we use luminescence, a light-sensitive soil mineral property, and numerical models to better understand different types of bioturbation. We provide a conceptual model that helps to determine which types of bioturbation processes occur in a soil and a numerical model that can derive quantitative process rates from luminescence measurements.
Laura Kuusemets, Ülo Mander, Jordi Escuer-Gatius, Alar Astover, Karin Kauer, Kaido Soosaar, and Mikk Espenberg
SOIL, 11, 1–15, https://doi.org/10.5194/soil-11-1-2025, https://doi.org/10.5194/soil-11-1-2025, 2025
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We investigated relationships between mineral nitrogen (N) fertilisation rates and additional manure amendment with different crop types through an analysis of soil environmental characteristics and microbiomes, soil N2O and N2 emissions as well as biomass production. The results show that wheat grew well at a fertilisation rate of 80 kg N ha−1, and newly introduced sorghum showed good potential for cultivation in temperate climates.
Ruizhe Wang and Xia Hu
SOIL, 10, 859–871, https://doi.org/10.5194/soil-10-859-2024, https://doi.org/10.5194/soil-10-859-2024, 2024
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This study characterized pore structure and soil organic carbon (SOC) fractions of aggregates during the seasonal freeze–thaw process. Freezing was associated with SOC accumulation, while the early stage of thawing was characterized by SOC loss. In the freezing period, pore structure could enhance SOC accumulation by promoting formation of > 80 μm pores. In the thawing period, pores of < 15 μm might inhibit SOC loss. These results present new perspectives on soil microstructure–SOC interactions.
Vítězslav Vlček, David Juřička, Martin Valtera, Helena Dvořáčková, Vojtěch Štulc, Michaela Bednaříková, Jana Šimečková, Peter Váczi, Miroslav Pohanka, Pavel Kapler, Miloš Barták, and Vojtěch Enev
SOIL, 10, 813–826, https://doi.org/10.5194/soil-10-813-2024, https://doi.org/10.5194/soil-10-813-2024, 2024
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The aim of this work was to evaluate the correlation between soil organic carbon (SOC) and various soil properties. Nine plots across an altitudinal range from 10 to 320 m were investigated in the deglaciated region of James Ross Island (Antarctica). Our results indicate that the primary factor influencing the SOC content is likely not altitude or coarse-fraction content; rather, other hard-to-quantify factors, such as the presence of liquid water during the summer period, impact SOC content.
Amicie A. Delahaie, Lauric Cécillon, Marija Stojanova, Samuel Abiven, Pierre Arbelet, Dominique Arrouays, François Baudin, Antonio Bispo, Line Boulonne, Claire Chenu, Jussi Heinonsalo, Claudy Jolivet, Kristiina Karhu, Manuel Martin, Lorenza Pacini, Christopher Poeplau, Céline Ratié, Pierre Roudier, Nicolas P. A. Saby, Florence Savignac, and Pierre Barré
SOIL, 10, 795–812, https://doi.org/10.5194/soil-10-795-2024, https://doi.org/10.5194/soil-10-795-2024, 2024
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This paper compares the soil organic carbon fractions obtained from a new thermal fractionation scheme and a well-known physical fractionation scheme on an unprecedented dataset of French topsoil samples. For each fraction, we use a machine learning model to determine its environmental drivers (pedology, climate, and land cover). Our results suggest that these two fractionation schemes provide different fractions, which means they provide complementary information.
Floriane Jamoteau, Emmanuel Doelsch, Nithavong Cam, Clément Levard, Thierry Woignier, Adrien Boulineau, François Saint-Antonin, Sufal Swaraj, Ghislain Gassier, Adrien Duvivier, Daniel Borschneck, Marie-Laure Pons, Perrine Chaurand, Vladimir Vidal, Nicolas Brouilly, and Isabelle Basile-Doelsch
EGUsphere, https://doi.org/10.5194/egusphere-2024-2933, https://doi.org/10.5194/egusphere-2024-2933, 2024
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This study shows that cultivating natural soils disrupts crucial mineral-organic associations, leading to carbon loss and reduced soil fertility. By analyzing soil samples from a forest and crop andosols, we found that these associations exist as amorphous coprecipitates (nanoCLICs). Cultivation reduces quantities of nanoCLICs by 50 %, highlighting their vulnerability to environmental changes and the need to develop strategies to preserve them to maintain soil fertility.
Lingfei Wang, Gab Abramowitz, Ying-Ping Wang, Andy Pitman, and Raphael A. Viscarra Rossel
SOIL, 10, 619–636, https://doi.org/10.5194/soil-10-619-2024, https://doi.org/10.5194/soil-10-619-2024, 2024
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Effective management of soil organic carbon (SOC) requires accurate knowledge of its distribution and factors influencing its dynamics. We identify the importance of variables in spatial SOC variation and estimate SOC stocks in Australia using various models. We find there are significant disparities in SOC estimates when different models are used, highlighting the need for a critical re-evaluation of land management strategies that rely on the SOC distribution derived from a single approach.
Tchodjowiè P. I. Kpemoua, Pierre Barré, Sabine Houot, François Baudin, Cédric Plessis, and Claire Chenu
SOIL, 10, 533–549, https://doi.org/10.5194/soil-10-533-2024, https://doi.org/10.5194/soil-10-533-2024, 2024
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Several agroecological management options foster soil organic C stock accrual. What is behind the persistence of this "additional" C? We used three different methodological approaches and >20 years of field experiments under temperate conditions to find out. We found that the additional C is less stable at the pluri-decadal scale than the baseline C. This highlights the need to maintain agroecological practices to keep these carbon stocks at a high level over time.
Jörg Schnecker, Theresa Böckle, Julia Horak, Victoria Martin, Taru Sandén, and Heide Spiegel
SOIL, 10, 521–531, https://doi.org/10.5194/soil-10-521-2024, https://doi.org/10.5194/soil-10-521-2024, 2024
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Microbial processes are driving the formation and decomposition of soil organic matter. In contrast to respiration and growth, microbial death rates currently lack distinct methods to be determined. Here, we propose a new approach to measure microbial death rates. This new approach to determine microbial death rates as well as dynamics of intracellular and extracellular DNA separately will help to improve concepts and models of C dynamics in soils in the future.
Laura Hondroudakis, Peter M. Kopittke, Ram C. Dalal, Meghan Barnard, and Zhe H. Weng
SOIL, 10, 451–465, https://doi.org/10.5194/soil-10-451-2024, https://doi.org/10.5194/soil-10-451-2024, 2024
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Land use change to cropping is known to greatly reduced organic carbon and nitrogen concentrations, but much remains unknown about the mechanisms influencing their persistence in soil. In a soil from a subtropical Australian cropping system, we demonstrate that organic carbon is protected by mineral associations but not particulate forms. Importantly, we also show that reversion from cropping to pasture or plantation can partially restore this organic carbon.
Qintana Si, Kangli Chen, Bin Wei, Yaowen Zhang, Xun Sun, and Junyi Liang
SOIL, 10, 441–450, https://doi.org/10.5194/soil-10-441-2024, https://doi.org/10.5194/soil-10-441-2024, 2024
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Our soil incubation experiment demonstrates that dissolved labile carbon substrate is a significant contributor to the soil particulate organic carbon pool. Dissolved carbon flow to particulate organic carbon is regulated by microbial biomass carbon and soil texture. The soil carbon model underestimates soil carbon sequestration when carbon flow from dissolved substrates to particulate organic carbon through microbial processes is not considered.
Sam J. Leuthold, Jocelyn M. Lavallee, Bruno Basso, William F. Brinton, and M. Francesca Cotrufo
SOIL, 10, 307–319, https://doi.org/10.5194/soil-10-307-2024, https://doi.org/10.5194/soil-10-307-2024, 2024
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We examined physical soil organic matter fractions to understand their relationship to temporal variability in crop yield at field scale. We found that interactions between crop productivity, topography, and climate led to variability in soil organic matter stocks among different yield stability zones. Our results imply that linkages between soil organic matter and yield stability may be scale-dependent and that particulate organic matter may be an indicator of unstable areas within croplands.
Johan Six, Sebastian Doetterl, Moritz Laub, Claude R. Müller, and Marijn Van de Broek
SOIL, 10, 275–279, https://doi.org/10.5194/soil-10-275-2024, https://doi.org/10.5194/soil-10-275-2024, 2024
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Soil C saturation has been tested in several recent studies and led to a debate about its existence. We argue that, to test C saturation, one should pay attention to six fundamental principles: the right measures, the right units, the right dispersive energy and application, the right soil type, the right clay type, and the right saturation level. Once we take care of those six rights across studies, we find support for a maximum of C stabilized by minerals and thus soil C saturation.
Norman Gentsch, Florin Laura Riechers, Jens Boy, Dörte Schweneker, Ulf Feuerstein, Diana Heuermann, and Georg Guggenberger
SOIL, 10, 139–150, https://doi.org/10.5194/soil-10-139-2024, https://doi.org/10.5194/soil-10-139-2024, 2024
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Cover crops have substantial impacts on soil properties, but so far it is not clear how long a legacy effect of cover cropping will remain in the soil. We found that cover crops attenuate negative effects on soil structure that come from soil cultivation. The combination of plants with different litter qualities and rhizodeposits in biodiverse cover crop mixtures can improve the positive effects of cover cropping on soil structure amelioration.
Che-Jen Hsiao, Pedro A. M. Leite, Ayumi Hyodo, and Thomas W. Boutton
SOIL, 10, 93–108, https://doi.org/10.5194/soil-10-93-2024, https://doi.org/10.5194/soil-10-93-2024, 2024
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Tree cover has increased in grasslands worldwide, with juniper and oak trees expanding in the southern Great Plains, USA. Here, we examine how these changes interact with geology to affect soil C, N, and P storage. Soil concentrations of these elements were significantly higher under trees than grasslands but increased more under trees growing on Edwards soils. Our results suggest that geology and vegetation change should be considered when predicting soil storage in dryland ecosystems globally.
David S. McLagan, Carina Esser, Lorenz Schwab, Jan G. Wiederhold, Jan-Helge Richard, and Harald Biester
SOIL, 10, 77–92, https://doi.org/10.5194/soil-10-77-2024, https://doi.org/10.5194/soil-10-77-2024, 2024
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Sorption of mercury in soils, aquifer materials, and sediments is primarily linked to organic matter. Using column experiments, mercury concentration, speciation, and stable isotope analyses, we show that large quantities of mercury in soil water and groundwater can be sorbed to inorganic minerals; sorption to the solid phase favours lighter isotopes. Data provide important insights on the transport and fate of mercury in soil–groundwater systems and particularly in low-organic-matter systems.
Marketa Stepanova, Martin Novak, Bohuslava Cejkova, Ivana Jackova, Frantisek Buzek, Frantisek Veselovsky, Jan Curik, Eva Prechova, Arnost Komarek, and Leona Bohdalkova
SOIL, 9, 623–640, https://doi.org/10.5194/soil-9-623-2023, https://doi.org/10.5194/soil-9-623-2023, 2023
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Biological N2 fixation helps to sustain carbon accumulation in peatlands and to remove CO2 from the atmosphere. Changes in N2 fixation may affect the dynamics of global change. Increasing inputs of reactive N from air pollution should lead to downregulation of N2 fixation. Data from three N-polluted peat bogs show an interplay of N2-fixation rates with 10 potential drivers of this process. N2 fixation was measurable only at one site characterized by high phosphorus and low sulfate availability.
Tatjana C. Speckert, Jeannine Suremann, Konstantin Gavazov, Maria J. Santos, Frank Hagedorn, and Guido L. B. Wiesenberg
SOIL, 9, 609–621, https://doi.org/10.5194/soil-9-609-2023, https://doi.org/10.5194/soil-9-609-2023, 2023
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Soil organic carbon (SOC) is key player in the global carbon cycle. Afforestation on pastures potentially alters organic matter input and SOC sequestration. We investigated the effects of a Picea abies L. afforestation sequence (0 to 130 years) on a former subalpine pasture on SOC stocks and dynamics. We found no difference in the SOC stock after 130 years of afforestation and thus no additional SOC sequestration. SOC composition was altered due to a modified SOC input following afforestation.
Lauren M. Gillespie, Nathalie Y. Triches, Diego Abalos, Peter Finke, Sophie Zechmeister-Boltenstern, Stephan Glatzel, and Eugenio Díaz-Pinés
SOIL, 9, 517–531, https://doi.org/10.5194/soil-9-517-2023, https://doi.org/10.5194/soil-9-517-2023, 2023
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Forest soil is potentially an important source or sink of greenhouse gases (CO2, N2O, and CH4), but this is affected by soil conditions. We studied how land inclination and soil/litter properties influence the flux of these gases. CO2 and N2O were more affected by inclination than CH4; all were affected by soil/litter properties. This study underlines the importance of inclination and soil/litter properties in predicting greenhouse gas fluxes from forest soil and potential source–sink balance.
Sastrika Anindita, Peter Finke, and Steven Sleutel
SOIL, 9, 443–459, https://doi.org/10.5194/soil-9-443-2023, https://doi.org/10.5194/soil-9-443-2023, 2023
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This study investigated how land use, through its impact on soil geochemistry, might indirectly control soil organic carbon (SOC) content in tropical volcanic soils in Indonesia. We analyzed SOC fractions, substrate-specific mineralization, and net priming of SOC. Our results indicated that the enhanced formation of aluminum (hydr)oxides promoted aggregation and physical occlusion of OC, which is consistent with the lesser degradability of SOC in agricultural soils.
Amicie A. Delahaie, Pierre Barré, François Baudin, Dominique Arrouays, Antonio Bispo, Line Boulonne, Claire Chenu, Claudy Jolivet, Manuel P. Martin, Céline Ratié, Nicolas P. A. Saby, Florence Savignac, and Lauric Cécillon
SOIL, 9, 209–229, https://doi.org/10.5194/soil-9-209-2023, https://doi.org/10.5194/soil-9-209-2023, 2023
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We characterized organic matter in French soils by analysing samples from the French RMQS network using Rock-Eval thermal analysis. We found that thermal analysis is appropriate to characterize large set of samples (ca. 2000) and provides interpretation references for Rock-Eval parameter values. This shows that organic matter in managed soils is on average more oxidized and more thermally stable and that some Rock-Eval parameters are good proxies for organic matter biogeochemical stability.
Britta Greenshields, Barbara von der Lühe, Harold J. Hughes, Christian Stiegler, Suria Tarigan, Aiyen Tjoa, and Daniela Sauer
SOIL, 9, 169–188, https://doi.org/10.5194/soil-9-169-2023, https://doi.org/10.5194/soil-9-169-2023, 2023
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Silicon (Si) research could provide complementary measures in sustainably cultivating oil-palm monocultures. Our study shows that current oil-palm management practices and topsoil erosion on oil-palm plantations in Indonesia have caused a spatial distribution of essential Si pools in soil. A lack of well-balanced Si levels in topsoil could negatively affect crop yield and soil fertility for future replanting at the same plantation site. Potential measures are suggested to maintain Si cycling.
Kenji Fujisaki, Tiphaine Chevallier, Antonio Bispo, Jean-Baptiste Laurent, François Thevenin, Lydie Chapuis-Lardy, Rémi Cardinael, Christine Le Bas, Vincent Freycon, Fabrice Bénédet, Vincent Blanfort, Michel Brossard, Marie Tella, and Julien Demenois
SOIL, 9, 89–100, https://doi.org/10.5194/soil-9-89-2023, https://doi.org/10.5194/soil-9-89-2023, 2023
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This paper presents a first comprehensive thesaurus for management practices driving soil organic carbon (SOC) storage. So far, a comprehensive thesaurus of management practices in agriculture and forestry has been lacking. It will help to merge datasets, a promising way to evaluate the impacts of management practices in agriculture and forestry on SOC. Identifying the drivers of SOC stock changes is of utmost importance to contribute to global challenges (climate change, food security).
Oliver van Straaten, Larissa Kulp, Guntars O. Martinson, Dan Paul Zederer, and Ulrike Talkner
SOIL, 9, 39–54, https://doi.org/10.5194/soil-9-39-2023, https://doi.org/10.5194/soil-9-39-2023, 2023
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Across northern Europe, millions of hectares of forest have been limed to counteract soil acidification and restore forest ecosystems. In this study, we investigated how restorative liming affects the forest soil organic carbon (SOC) stocks and correspondingly ecosystem greenhouse gas fluxes. We found that the magnitude and direction of SOC stock changes hinge on the inherent site characteristics, namely, forest type, soil texture, initial soil pH, and initial soil SOC stocks (before liming).
Junxiao Pan, Jinsong Wang, Dashuan Tian, Ruiyang Zhang, Yang Li, Lei Song, Jiaming Yang, Chunxue Wei, and Shuli Niu
SOIL, 8, 687–698, https://doi.org/10.5194/soil-8-687-2022, https://doi.org/10.5194/soil-8-687-2022, 2022
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We found that climatic, edaphic, plant and microbial variables jointly affect soil inorganic carbon (SIC) stock in Tibetan grasslands, and biotic factors have a larger contribution than abiotic factors to the variation in SIC stock. The effects of microbial and plant variables on SIC stock weakened with soil depth, while the effects of edaphic variables strengthened. The contrasting responses and drivers of SIC stock highlight differential mechanisms underlying SIC preservation with soil depth.
Yifeng Zhang, Sen Dou, Batande Sinovuyo Ndzelu, Rui Ma, Dandan Zhang, Xiaowei Zhang, Shufen Ye, and Hongrui Wang
SOIL, 8, 605–619, https://doi.org/10.5194/soil-8-605-2022, https://doi.org/10.5194/soil-8-605-2022, 2022
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How to effectively convert corn straw into humic substances and return them to the soil in a relatively stable form is a concerning topic. Through a 360 d field experiment under equal carbon (C) mass, we found that return of the fermented corn straw treated with Trichoderma reesei to the field is more valuable and conducive to increasing easily oxidizable organic C, humus C content, and carbon pool management index than the direct application of corn straw.
Ling Mao, Shaoming Ye, and Shengqiang Wang
SOIL, 8, 487–505, https://doi.org/10.5194/soil-8-487-2022, https://doi.org/10.5194/soil-8-487-2022, 2022
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Soil ecological stoichiometry offers a tool to explore the distribution, cycling, limitation, and balance of chemical elements. This study improved the understanding of soil organic carbon and nutrient dynamics in tea plantation ecosystems and also provided supplementary information for soil ecological stoichiometry in global terrestrial ecosystems.
Steffen Schlüter, Tim Roussety, Lena Rohe, Vusal Guliyev, Evgenia Blagodatskaya, and Thomas Reitz
SOIL, 8, 253–267, https://doi.org/10.5194/soil-8-253-2022, https://doi.org/10.5194/soil-8-253-2022, 2022
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We combined microstructure analysis via X-ray CT with carbon mineralization analysis via respirometry of intact soil cores from different land uses. We found that the amount of particulate organic matter (POM) exerted a dominant control on carbon mineralization in well-aerated topsoils, whereas soil moisture and macroporosity did not play role. This is because carbon mineralization mainly occurs in microbial hotspots around degrading POM, where it is decoupled from conditions of the bulk soil.
Roberta Pulcher, Enrico Balugani, Maurizio Ventura, Nicolas Greggio, and Diego Marazza
SOIL, 8, 199–211, https://doi.org/10.5194/soil-8-199-2022, https://doi.org/10.5194/soil-8-199-2022, 2022
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Biochar, a solid product from the thermal conversion of biomass, can be used as a climate change mitigation strategy, since it can sequester carbon from the atmosphere and store it in the soil. The aim of this study is to assess the potential of biochar as a mitigation strategy in the long term, by modelling the results obtained from an 8-year field experiment. As far as we know, this is the first time that a model for biochar degradation has been validated with long-term field data.
Daniel Rath, Nathaniel Bogie, Leonardo Deiss, Sanjai J. Parikh, Daoyuan Wang, Samantha Ying, Nicole Tautges, Asmeret Asefaw Berhe, Teamrat A. Ghezzehei, and Kate M. Scow
SOIL, 8, 59–83, https://doi.org/10.5194/soil-8-59-2022, https://doi.org/10.5194/soil-8-59-2022, 2022
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Storing C in subsoils can help mitigate climate change, but this requires a better understanding of subsoil C dynamics. We investigated changes in subsoil C storage under a combination of compost, cover crops (WCC), and mineral fertilizer and found that systems with compost + WCC had ~19 Mg/ha more C after 25 years. This increase was attributed to increased transport of soluble C and nutrients via WCC root pores and demonstrates the potential for subsoil C storage in tilled agricultural systems.
Zuzana Frkova, Chiara Pistocchi, Yuliya Vystavna, Katerina Capkova, Jiri Dolezal, and Federica Tamburini
SOIL, 8, 1–15, https://doi.org/10.5194/soil-8-1-2022, https://doi.org/10.5194/soil-8-1-2022, 2022
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Phosphorus (P) is essential for life. We studied microbial processes driving the P cycle in soils developed on the same rock but with different ages (0–100 years) in a cold desert. Compared to previous studies under cold climate, we found much slower weathering of P-containing minerals of soil development, likely due to aridity. However, microbes dominate short-term dynamics and progressively redistribute P from the rock into more available forms, making it available for plants at later stages.
Carrie L. Thomas, Boris Jansen, E. Emiel van Loon, and Guido L. B. Wiesenberg
SOIL, 7, 785–809, https://doi.org/10.5194/soil-7-785-2021, https://doi.org/10.5194/soil-7-785-2021, 2021
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Plant organs, such as leaves, contain a variety of chemicals that are eventually deposited into soil and can be useful for studying organic carbon cycling. We performed a systematic review of available data of one type of plant-derived chemical, n-alkanes, to determine patterns of degradation or preservation from the source plant to the soil. We found that while there was degradation in the amount of n-alkanes from plant to soil, some aspects of the chemical signature were preserved.
Benjamin Bukombe, Peter Fiener, Alison M. Hoyt, Laurent K. Kidinda, and Sebastian Doetterl
SOIL, 7, 639–659, https://doi.org/10.5194/soil-7-639-2021, https://doi.org/10.5194/soil-7-639-2021, 2021
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Through a laboratory incubation experiment, we investigated the spatial patterns of specific maximum heterotrophic respiration in tropical African mountain forest soils developed from contrasting parent material along slope gradients. We found distinct differences in soil respiration between soil depths and geochemical regions related to soil fertility and the chemistry of the soil solution. The topographic origin of our samples was not a major determinant of the observed rates of respiration.
Patricia Merdy, Yves Lucas, Bruno Coulomb, Adolpho J. Melfi, and Célia R. Montes
SOIL, 7, 585–594, https://doi.org/10.5194/soil-7-585-2021, https://doi.org/10.5194/soil-7-585-2021, 2021
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Transfer of organic C from topsoil to deeper horizons and the water table is little documented, especially in equatorial environments, despite high primary productivity in the evergreen forest. Using column experiments with podzol soil and a percolating solution sampled in an Amazonian podzol area, we show how the C-rich Bh horizon plays a role in natural organic matter transfer and Si, Fe and Al mobility after a kaolinitic layer transition, thus giving insight to the genesis of tropical podzol.
Jörg Schnecker, D. Boone Meeden, Francisco Calderon, Michel Cavigelli, R. Michael Lehman, Lisa K. Tiemann, and A. Stuart Grandy
SOIL, 7, 547–561, https://doi.org/10.5194/soil-7-547-2021, https://doi.org/10.5194/soil-7-547-2021, 2021
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Drought and flooding challenge agricultural systems and their management globally. Here we investigated the response of soils from long-term agricultural field sites with simple and diverse crop rotations to either drought or flooding. We found that irrespective of crop rotation complexity, soil and microbial properties were more resistant to flooding than to drought and highly resilient to drought and flooding during single or repeated stress pulses.
Mario Reichenbach, Peter Fiener, Gina Garland, Marco Griepentrog, Johan Six, and Sebastian Doetterl
SOIL, 7, 453–475, https://doi.org/10.5194/soil-7-453-2021, https://doi.org/10.5194/soil-7-453-2021, 2021
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In deeply weathered tropical rainforest soils of Africa, we found that patterns of soil organic carbon stocks differ between soils developed from geochemically contrasting parent material due to differences in the abundance of organo-mineral complexes, the presence/absence of chemical stabilization mechanisms of carbon with minerals and the presence of fossil organic carbon from sedimentary rocks. Physical stabilization mechanisms by aggregation provide additional protection of soil carbon.
Fabian Kalks, Gabriel Noren, Carsten W. Mueller, Mirjam Helfrich, Janet Rethemeyer, and Axel Don
SOIL, 7, 347–362, https://doi.org/10.5194/soil-7-347-2021, https://doi.org/10.5194/soil-7-347-2021, 2021
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Sedimentary rocks contain organic carbon that may end up as soil carbon. However, this source of soil carbon is overlooked and has not been quantified sufficiently. We analysed 10 m long sediment cores with three different sedimentary rocks. All sediments contain considerable amounts of geogenic carbon contributing 3 %–12 % to the total soil carbon below 30 cm depth. The low 14C content of geogenic carbon can result in underestimations of soil carbon turnover derived from 14C data.
Maximilian Kirsten, Robert Mikutta, Didas N. Kimaro, Karl-Heinz Feger, and Karsten Kalbitz
SOIL, 7, 363–375, https://doi.org/10.5194/soil-7-363-2021, https://doi.org/10.5194/soil-7-363-2021, 2021
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Mineralogical combinations of aluminous clay and pedogenic Fe oxides revealed significant effects on soil structure and related organic carbon (OC) storage.
The mineralogical combination resulting in the largest aggregate stability does not better preserve OC during conversion of forests into croplands.
Structural changes in the direction of smaller mean weight diameters do not cancel out the stabilizing effect of soil minerals.
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Short summary
Global significance of metals (extractable Fe and Al phases) to control organic matter (OM) in recognized. Next key questions include the identification of their localization and mechanism behind OM–metal relationships. Across 23 soils of contrasting mineralogy, Fe and Al phases were mainly associated with microbially processed OM as meso-density microaggregates. OM- and metal-rich nanocomposites with a narrow OM : metal ratio likely acted as binding agents. A new conceptual model was proposed.
Global significance of metals (extractable Fe and Al phases) to control organic matter (OM) in...
