Articles | Volume 6, issue 2
Original research article 29 Sep 2020
Original research article | 29 Sep 2020
Land-use perturbations in ley grassland decouple the degradation of ancient soil organic matter from the storage of newly derived carbon inputs
Marco Panettieri et al.
No articles found.
Justine Barthod, Cornélia Rumpel, Remigio Paradelo, and Marie-France Dignac
SOIL, 2, 673–683,Short summary
In this study we evaluated CO2 emissions during composting of green wastes with clay and/or biochar in the presence and absence of worms, as well as the effect of those amendments on carbon mineralization after application to soil. Our results indicated that the addition of clay or clay–biochar mixture reduced carbon mineralization during co-composting without worms by up to 44 %. In the presence of worms, CO2 emissions during composting increased for all treatments except for the low clay dose.
Related subject area
Soils and biogeochemical cyclingIron and aluminum association with microbially processed organic matter via meso-density aggregate formation across soils: organo-metallic glue hypothesisSwitch of fungal to bacterial degradation in natural, drained and rewetted oligotrophic peatlands reflected in δ15N and fatty acid compositionCatchment export of base cations: improved mineral dissolution kinetics influence the role of water transit timeBoreal-forest soil chemistry drives soil organic carbon bioreactivity along a 314-year fire chronosequenceRamped thermal analysis for isolating biologically meaningful soil organic matter fractions with distinct residence timesVariations in soil chemical and physical properties explain basin-wide Amazon forest soil carbon concentrationsLithology- and climate-controlled soil aggregate-size distribution and organic carbon stability in the Peruvian AndesEvaluating the effects of soil erosion and productivity decline on soil carbon dynamics using a model-based approachBase cations in the soil bank: non-exchangeable pools may sustain centuries of net loss to forestry and leachingShort-range-order minerals as powerful factors explaining deep soil organic carbon stock distribution: the case of a coffee agroforestry plantation on Andosols in Costa RicaA new look at an old concept: using 15N2O isotopomers to understand the relationship between soil moisture and N2O production pathwaysAssessing the impact of acid rain and forest harvest intensity with the HD-MINTEQ model – soil chemistry of three Swedish conifer sites from 1880 to 2080Dynamic modelling of weathering rates – the benefit over steady-state modellingAluminium and base cation chemistry in dynamic acidification models – need for a reappraisal?Challenges of soil carbon sequestration in the NENA regionContinental soil drivers of ammonium and nitrate in AustraliaComment on “Soil organic stocks are systematically overestimated by misuse of the parameters bulk density and rock fragment content” by Poeplau et al. (2017)Hot regions of labile and stable soil organic carbon in Germany – Spatial variability and driving factorsPotential short-term losses of N2O and N2 from high concentrations of biogas digestate in arable soilsA deeper look at the relationship between root carbon pools and the vertical distribution of the soil carbon poolNitrate retention capacity of milldam-impacted legacy sediments and relict A horizon soilsProcess-oriented modelling to identify main drivers of erosion-induced carbon fluxesThermal alteration of soil organic matter properties: a systematic study to infer response of Sierra Nevada climosequence soils to forest firesTimescales of carbon turnover in soils with mixed crystalline mineralogiesGreater soil carbon stocks and faster turnover rates with increasing agricultural productivityThree-dimensional soil organic matter distribution, accessibility and microbial respiration in macroaggregates using osmium staining and synchrotron X-ray computed tomographyLong-term elevation of temperature affects organic N turnover and associated N2O emissions in a permanent grassland soilSoil fauna: key to new carbon modelsTillage-induced short-term soil organic matter turnover and respirationSimultaneous quantification of depolymerization and mineralization rates by a novel 15N tracing modelSoil CO2 efflux in an old-growth southern conifer forest (Agathis australis) – magnitude, components and controlsThermal alteration of soil physico-chemical properties: a systematic study to infer response of Sierra Nevada climosequence soils to forest firesGone or just out of sight? The apparent disappearance of aromatic litter components in soilsSoil properties and not inputs control carbon : nitrogen : phosphorus ratios in cropped soils in the long termOn the rebound: soil organic carbon stocks can bounce back to near forest levels when agroforests replace agriculture in southern IndiaEffect of biochar and liming on soil nitrous oxide emissions from a temperate maize cropping systemBiogeochemical cycles and biodiversity as key drivers of ecosystem services provided by soils14C in cropland soil of a long-term field trial – experimental variability and implications for estimating carbon turnoverA new synthesis for terrestrial nitrogen inputsAmino acid and N mineralization dynamics in heathland soil after long-term warming and repetitive droughtInvestigating microbial transformations of soil organic matter: synthesizing knowledge from disparate fields to guide new experimentationThe soil N cycle: new insights and key challengesLitter decomposition rate and soil organic matter quality in a patchwork heathland of southern NorwayPermafrost soils and carbon cycling
Rota Wagai, Masako Kajiura, and Maki Asano
SOIL, 6, 597–627,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.
Miriam Groß-Schmölders, Pascal von Sengbusch, Jan Paul Krüger, Kristy Klein, Axel Birkholz, Jens Leifeld, and Christine Alewell
SOIL, 6, 299–313,Short summary
Degradation turns peatlands into a source of CO2. There is no cost- or time-efficient method available for indicating peatland hydrology or the success of restoration. We found that 15N values have a clear link to microbial communities and degradation. We identified trends in natural, drained and rewetted conditions and concluded that 15N depth profiles can act as a reliable and efficient tool for obtaining information on current hydrology, restoration success and drainage history.
Martin Erlandsson Lampa, Harald U. Sverdrup, Kevin H. Bishop, Salim Belyazid, Ali Ameli, and Stephan J. Köhler
SOIL, 6, 231–244,Short summary
In this study, we demonstrate how new equations describing base cation release from mineral weathering can reproduce patterns in observations from stream and soil water. This is a major step towards modeling base cation cycling on the catchment scale, which would be valuable for defining the highest sustainable rates of forest harvest and levels of acidifying deposition.
Benjamin Andrieux, David Paré, Julien Beguin, Pierre Grondin, and Yves Bergeron
SOIL, 6, 195–213,Short summary
Our study aimed to disentangle the contribution of several drivers to explaining the proportion of soil carbon that can be released to CO2 through microbial respiration. We found that boreal-forest soil chemistry is an important driver of the amount of carbon that microbes can process. Our results emphasize the need to include the effects of soil chemistry into models of carbon cycling to better anticipate the role played by boreal-forest soils in carbon-cycle–climate feedbacks.
Jonathan Sanderman and A. Stuart Grandy
SOIL, 6, 131–144,Short summary
Soils contain one of the largest and most dynamic pools of carbon on Earth, yet scientists still struggle to understand the reactivity and fate of soil organic matter upon disturbance. In this study, we found that with increasing thermal stability, the turnover time of organic matter increased from decades to centuries with a concurrent shift in chemical composition. In this proof-of-concept study, we found that ramped thermal analyses can provide new insights for understanding soil carbon.
Carlos Alberto Quesada, Claudia Paz, Erick Oblitas Mendoza, Oliver Lawrence Phillips, Gustavo Saiz, and Jon Lloyd
SOIL, 6, 53–88,Short summary
Amazon soils hold as much carbon (C) as is contained in the vegetation. In this work we sampled soils across 8 different Amazonian countries to try to understand which soil properties control current Amazonian soil C concentrations. We confirm previous knowledge that highly developed soils hold C through clay content interactions but also show a previously unreported mechanism of soil C stabilization in the younger Amazonian soil types which hold C through aluminium organic matter interactions.
Songyu Yang, Boris Jansen, Samira Absalah, Rutger L. van Hall, Karsten Kalbitz, and Erik L. H. Cammeraat
SOIL, 6, 1–15,Short summary
Soils store large carbon and are important for global warming. We do not know what factors are important for soil carbon storage in the alpine Andes or how they work. We studied how rainfall affects soil carbon storage related to soil structure. We found soil structure is not important, but soil carbon storage and stability controlled by rainfall is dependent on rocks under the soils. The results indicate that we should pay attention to the rocks when we study soil carbon storage in the Andes.
Samuel Bouchoms, Zhengang Wang, Veerle Vanacker, and Kristof Van Oost
SOIL, 5, 367–382,Short summary
Soil erosion has detrimental effects on soil fertility which can reduce carbon inputs coming from crops to soils. Our study integrated this effect into a model linking soil organic carbon (SOC) dynamics to erosion and crop productivity. When compared to observations, the inclusion of productivity improved SOC loss predictions. Over centuries, ignoring crop productivity evolution in models could result in underestimating SOC loss and overestimating C exchanged with the atmosphere.
Nicholas P. Rosenstock, Johan Stendahl, Gregory van der Heijden, Lars Lundin, Eric McGivney, Kevin Bishop, and Stefan Löfgren
SOIL, 5, 351–366,Short summary
Biofuel harvests from forests involve large removals of available nutrients, necessitating accurate measurements of soil nutrient stocks. We found that dilute hydrochloric acid extractions from soils released far more Ca, Na, and K than classical salt–extracted exchangeable nutrient pools. The size of these acid–extractable pools may indicate that forest ecosystems could sustain greater biomass extractions of Ca, Mg, and K than are predicted from salt–extracted exchangeable base cation pools.
Tiphaine Chevallier, Kenji Fujisaki, Olivier Roupsard, Florian Guidat, Rintaro Kinoshita, Elias de Melo Viginio Filho, Peter Lehner, and Alain Albrecht
SOIL, 5, 315–332,Short summary
Soil organic carbon (SOC) is the largest terrestrial C stock. Andosols of volcanic areas hold particularly large stocks (e.g. from 24 to 72 kgC m−2 in the upper 2 m of soil) as determined via MIR spectrometry at our Costa Rican study site: a 1 km2 basin covered by coffee agroforestry. Andic soil properties explained this high variability, which did not correlate with stocks in the upper 20 cm of soil. Topography and pedogenesis are needed to understand the SOC stocks at landscape scales.
Katelyn A. Congreves, Trang Phan, and Richard E. Farrell
SOIL, 5, 265–274,Short summary
There are surprising grey areas in the precise quantification of pathways that produce nitrous oxide, a potent greenhouse gas, as influenced by soil moisture. Here, we take a new look at a classic study but use isotopomers as a powerful tool to determine the source pathways of nitrous oxide as regulated by soil moisture. Our results support earlier research, but we contribute scientific advancements by providing models that enable quantifying source partitioning rather than just inferencing.
Eric McGivney, Jon Petter Gustafsson, Salim Belyazid, Therese Zetterberg, and Stefan Löfgren
SOIL, 5, 63–77,Short summary
Forest management may lead to long-term soil acidification due to the removal of base cations during harvest. By means of the HD-MINTEQ model, we compared the acidification effects of harvesting with the effects of historical acid rain at three forested sites in Sweden. The effects of harvesting on pH were predicted to be much smaller than those resulting from acid deposition during the 20th century. There were only very small changes in predicted weathering rates due to acid rain or harvest.
Veronika Kronnäs, Cecilia Akselsson, and Salim Belyazid
SOIL, 5, 33–47,Short summary
Weathering rates in forest soils are important for sustainable forestry but cannot be measured. In this paper, we have modelled weathering with the commonly used PROFILE model as well as with the dynamic model ForSAFE, better suited to a changing climate with changing human activities but never before tested for weathering calculations. We show that ForSAFE gives comparable weathering rates to PROFILE and that it shows the variation in weathering with time and works well for scenario modelling.
Jon Petter Gustafsson, Salim Belyazid, Eric McGivney, and Stefan Löfgren
SOIL, 4, 237–250,Short summary
This paper investigates how different dynamic soil chemistry models describe the processes governing aluminium and base cations in acid soil waters. We find that traditional cation-exchange equations, which are still used in many models, diverge from state-of-the-art complexation submodels such as WHAM, SHM, and NICA-Donnan when large fluctuations in pH or ionic strength occur. In conclusion, the complexation models provide a better basis for the modelling of chemical dynamics in acid soils.
Talal Darwish, Thérèse Atallah, and Ali Fadel
SOIL, 4, 225–235,Short summary
This paper is part of the GSP-ITPS effort to produce a global SOC map and update information on C stocks using old and new soil information to assess the potential for enhanced C sequestration in dry land areas of the NENA region. We used the DSMW from FAO-UNESCO (2007), focusing on organic and inorganic content in 0.3 m of topsoil and 0.7 m of subsoil, to discuss the human factors affecting the accumulation of organic C and the fate of inorganic C.
Juhwan Lee, Gina M. Garland, and Raphael A. Viscarra Rossel
SOIL, 4, 213–224,Short summary
Soil nitrogen (N) is an essential element for plant growth, but its plant-available forms are subject to loss from the environment by leaching and gaseous emissions. Still, factors controlling soil mineral N concentrations at large spatial scales are not well understood. We determined and discussed primary soil controls over the concentrations of NH4+ and NO3− at the continental scale of Australia while considering specific dominant land use patterns on a regional basis.
Eleanor Ursula Hobley, Brian Murphy, and Aaron Simmons
SOIL, 4, 169–171,Short summary
This research evaluates equations to calculate soil organic carbon (SOC) stocks. Although various equations exist for SOC stock calculations, we recommend using the simplest equation with THE lowest associated errors. Adjusting SOC stock calculations for rock content is essential. Using the mass proportion of rocks to do so minimizes error.
Cora Vos, Angélica Jaconi, Anna Jacobs, and Axel Don
SOIL, 4, 153–167,Short summary
Soil organic carbon sequestration can be facilitated by agricultural management, but its influence is not the same on all soil carbon pools. We assessed how soil organic carbon is distributed among C pools in Germany, identified factors influencing this distribution and identified regions with high vulnerability to C losses. Explanatory variables were soil texture, C / N ratio, soil C content and pH. For some regions, the drivers were linked to the land-use history as heathlands or peatlands.
Sebastian Rainer Fiedler, Jürgen Augustin, Nicole Wrage-Mönnig, Gerald Jurasinski, Bertram Gusovius, and Stephan Glatzel
SOIL, 3, 161–176,Short summary
Injection of biogas digestates (BDs) is suspected to increase losses of N2O and thus to counterbalance prevented NH3 emissions. We determined N2O and N2 losses after mixing high concentrations of BD into two soils by an incubation under an artificial helium–oxygen atmosphere. Emissions did not increase with the application rate of BD, probably due to an inhibitory effect of the high NH4+ content in BD on nitrification. However, cumulated gaseous N losses may effectively offset NH3 reductions.
Ranae Dietzel, Matt Liebman, and Sotirios Archontoulis
SOIL, 3, 139–152,Short summary
Roots deeper in the soil are made up of more carbon and less nitrogen compared to roots at shallower depths, which may help explain deep-carbon origin. A comparison of prairie and maize rooting systems showed that in moving from prairie to maize, a large, structural-tissue-dominated root carbon pool with slow turnover concentrated at shallow depths was replaced by a small, nonstructural-tissue-dominated root carbon pool with fast turnover evenly distributed in the soil profile.
Julie N. Weitzman and Jason P. Kaye
SOIL, 3, 95–112,Short summary
Prior research found nitrate losses in mid-Atlantic streams following drought but no mechanistic explanation. We aim to understand how legacy sediments influence soil–stream nitrate transfer. We found that surface legacy sediments do not retain excess nitrate inputs well; once exposed, previously buried soils experience the largest drought-induced nitrate losses; and, restoration that reconnects stream and floodplain via legacy sediment removal may initially cause high losses of nitrate.
Florian Wilken, Michael Sommer, Kristof Van Oost, Oliver Bens, and Peter Fiener
SOIL, 3, 83–94,Short summary
Model-based analyses of the effect of soil erosion on carbon (C) dynamics are associated with large uncertainties partly resulting from oversimplifications of erosion processes. This study evaluates the need for process-oriented modelling to analyse erosion-induced C fluxes in different catchments. The results underline the importance of a detailed representation of tillage and water erosion processes. For water erosion, grain-size-specific transport is essential to simulate lateral C fluxes.
Samuel N. Araya, Marilyn L. Fogel, and Asmeret Asefaw Berhe
SOIL, 3, 31–44,Short summary
This research investigates how fires of different intensities affect soil organic matter properties. This study identifies critical temperature thresholds of significant soil organic matter changes. Findings from this study will contribute towards estimating the amount and rate of changes in soil carbon, nitrogen, and other essential soil properties that can be expected from fires of different intensities under anticipated climate change scenarios.
Lesego Khomo, Susan Trumbore, Carleton R. Bern, and Oliver A. Chadwick
SOIL, 3, 17–30,Short summary
We evaluated mineral control of organic carbon dynamics by relating the content and age of carbon stored in soils of varied mineralogical composition found in the landscapes of Kruger National Park, South Africa. Carbon associated with smectite clay minerals, which have stronger surface–organic matter interactions, averaged about a thousand years old, while most soil carbon was only decades to centuries old and was associated with iron and aluminum oxide minerals.
Jonathan Sanderman, Courtney Creamer, W. Troy Baisden, Mark Farrell, and Stewart Fallon
SOIL, 3, 1–16,Short summary
Knowledge of how soil carbon stocks and flows change in response to agronomic management decisions is a critical step in devising management strategies that best promote food security while mitigating greenhouse gas emissions. Here, we present 40 years of data demonstrating that increasing productivity both leads to greater carbon stocks and accelerates the decomposition of soil organic matter, thus providing more nutrients back to the crop.
Barry G. Rawlins, Joanna Wragg, Christina Reinhard, Robert C. Atwood, Alasdair Houston, R. Murray Lark, and Sebastian Rudolph
SOIL, 2, 659–671,Short summary
We do not understand processes by which soil bacteria and fungi feed on soil organic matter (SOM). Previous research suggests the location of SOM in aggregates may influence whether bacteria can feed on it more easily. We did an experiment to identify the distribution of SOM on very small scales within nine soil aggregates. There was no clear evidence that the distribution of organic matter influenced how easily the organic matter was fed upon by bacteria.
Anne B. Jansen-Willems, Gary J. Lanigan, Timothy J. Clough, Louise C. Andresen, and Christoph Müller
SOIL, 2, 601–614,Short summary
Legacy effects of increased temperature on both nitrogen (N) transformation rates and nitrous oxide (N2O) emissions from permanent temperate grassland soil were evaluated. A new source-partitioning model showed the importance of oxidation of organic N as a source of N2O. Gross organic (and not inorganic) N transformation rates decreased in response to the prior soil warming treatment. This was also reflected in reduced N2O emissions associated with organic N oxidation and denitrification.
Juliane Filser, Jack H. Faber, Alexei V. Tiunov, Lijbert Brussaard, Jan Frouz, Gerlinde De Deyn, Alexei V. Uvarov, Matty P. Berg, Patrick Lavelle, Michel Loreau, Diana H. Wall, Pascal Querner, Herman Eijsackers, and Juan José Jiménez
SOIL, 2, 565–582,Short summary
Soils store more than 3 times as much carbon than the atmosphere, but global carbon models still suffer from large uncertainty. We argue that this may be due to the fact that soil animals are not taken into account in such models. They dig, eat and distribute dead organic matter and microorganisms, and the quantity of their activity is often huge. Soil animals affect microbial activity, soil water content, soil structure, erosion and plant growth – and all of this affects carbon cycling.
Sebastian Rainer Fiedler, Peter Leinweber, Gerald Jurasinski, Kai-Uwe Eckhardt, and Stephan Glatzel
SOIL, 2, 475–486,Short summary
We applied Py-FIMS, CO2 measurements and hot-water extraction on farmland to investigate short-term effects of tillage on soil organic matter (SOM) turnover. SOM composition changed on the temporal scale of days and the changes varied significantly under different types of amendment. Particularly obvious were the turnover of lignin-derived substances and depletion of carbohydrates due to soil respiration. The long-term impact of biogas digestates on SOM stocks should be examined more closely.
Louise C. Andresen, Anna-Karin Björsne, Samuel Bodé, Leif Klemedtsson, Pascal Boeckx, and Tobias Rütting
SOIL, 2, 433–442,Short summary
In soil the constant transport of nitrogen (N) containing compounds from soil organic matter and debris out into the soil water, is controlled by soil microbes and enzymes that literally cut down polymers (such as proteins) into single amino acids (AA), hereafter microbes consume AAs and excrete ammonium back to the soil. We developed a method for analysing N turnover and flow of organic N, based on parallel 15N tracing experiments. The numerical model gives robust and simultaneous quantification.
Luitgard Schwendenmann and Cate Macinnis-Ng
SOIL, 2, 403–419,Short summary
This is the first study quantifying total soil CO2 efflux, heterotrophic and autotrophic respiration in an old-growth kauri forest. Root biomass explained a high proportion of the spatial variation suggesting that soil CO2 efflux in this forest is not only directly affected by the amount of autotrophic respiration but also by the supply of C through roots and mycorrhiza. Our findings also suggest that biotic factors such as tree structure should be investigated in soil carbon related studies.
Samuel N. Araya, Mercer Meding, and Asmeret Asefaw Berhe
SOIL, 2, 351–366,Short summary
Using laboratory heating, we studied effects of fire intensity on important topsoil characteristics. This study identifies critical temperature thresholds for significant physical and chemical changes in soils that developed under different climate regimes. Findings from this study will contribute towards estimating the amount and rate of change in essential soil properties that can be expected from topsoil exposure to different intensity fires under anticipated climate change scenarios.
Thimo Klotzbücher, Karsten Kalbitz, Chiara Cerli, Peter J. Hernes, and Klaus Kaiser
SOIL, 2, 325–335,Short summary
Uncertainties concerning stabilization of organic compounds in soil limit our basic understanding on soil organic matter (SOM) formation and our ability to model and manage effects of global change on SOM stocks. One controversially debated aspect is the contribution of aromatic litter components, such as lignin and tannins, to stable SOM forms. Here, we summarize and discuss the inconsistencies and propose research options to clear them.
Emmanuel Frossard, Nina Buchmann, Else K. Bünemann, Delwende I. Kiba, François Lompo, Astrid Oberson, Federica Tamburini, and Ouakoltio Y. A. Traoré
SOIL, 2, 83–99,
H. C. Hombegowda, O. van Straaten, M. Köhler, and D. Hölscher
SOIL, 2, 13–23,Short summary
Incorporating trees into agriculture systems provides numerous environmental services. In this chronosequence study conducted across S. India, we found that agroforestry systems (AFSs), specifically home gardens, coffee, coconut and mango, can cause soil organic carbon (SOC) to rebound to forest levels. We established 224 plots in 56 clusters and compared the SOC between natural forests, agriculture and AFSs. SOC sequestered depending on AFS type, environmental conditions and tree diversity.
R. Hüppi, R. Felber, A. Neftel, J. Six, and J. Leifeld
SOIL, 1, 707–717,Short summary
Biochar is considered an opportunity to tackle major environmental issues in agriculture. Adding pyrolised organic residues to soil may sequester carbon, increase yields and reduce nitrous oxide emissions from soil. It is unknown, whether the latter is induced by changes in soil pH. We show that biochar application substantially reduces nitrous oxide emissions from a temperate maize cropping system. However, the reduction was only achieved with biochar but not with liming.
P. Smith, M. F. Cotrufo, C. Rumpel, K. Paustian, P. J. Kuikman, J. A. Elliott, R. McDowell, R. I. Griffiths, S. Asakawa, M. Bustamante, J. I. House, J. Sobocká, R. Harper, G. Pan, P. C. West, J. S. Gerber, J. M. Clark, T. Adhya, R. J. Scholes, and M. C. Scholes
SOIL, 1, 665–685,Short summary
Soils play a pivotal role in major global biogeochemical cycles (carbon, nutrient, and water), while hosting the largest diversity of organisms on land. Soils deliver fundamental ecosystem services, and management to change a soil process in support of one ecosystem service can affect other services. We provide a critical review of these aspects, and conclude that, although there are knowledge gaps, enough is known improve soils globally, and we suggest actions to start this process.
J. Leifeld and J. Mayer
SOIL, 1, 537–542,Short summary
We present 14C data for field replicates of a controlled agricultural long-term experiment. We show that 14C variability is, on average, 12 times that of the analytical precision of the 14C measurement. Experimental 14C variability is related to neither management nor soil depth. Application of a simple carbon turnover model reveals that experimental variability of radiocarbon results in higher absolute uncertainties of estimated carbon turnover time for deeper soil layers.
B. Z. Houlton and S. L. Morford
SOIL, 1, 381–397,Short summary
Nitrogen is necessary for life; this element is found in all DNA and protein molecules on Earth. Nitrogen also regulates the CO2 uptake capacity of land ecosystems, with important consequences for climate change. Here we provide evidence for a new source of nitrogen that is found in many of the rock materials on which natural ecosystems form. The idea that rocks are a widely distributed source of nitrogen challenges the standard paradigm of botany, soil, and ecosystem science.
L. C. Andresen, S. Bode, A. Tietema, P. Boeckx, and T. Rütting
SOIL, 1, 341–349,
S. A. Billings, L. K. Tiemann, F. Ballantyne IV, C. A. Lehmeier, and K. Min
SOIL, 1, 313–330,Short summary
We highlight observations relevant to soil organic matter (SOM) decay and retention but often emanating from disparate fields. First, we describe relevant natural and artificial aquatic environments. Second, we describe how intrinsic patterns of decay kinetics for purified soil substrates are useful for defining baseline rates. Third, we describe theoretical advances important for the discipline. Last, we describe how these advances can be used to unravel the mysteries of deep SOM persistence.
J. W. van Groenigen, D. Huygens, P. Boeckx, Th. W. Kuyper, I. M. Lubbers, T. Rütting, and P. M. Groffman
SOIL, 1, 235–256,
G. Certini, L. S. Vestgarden, C. Forte, and L. Tau Strand
SOIL, 1, 207–216,Short summary
We studied a heathland area of Norway consisting in a patchwork of Calluna, Molinia or Sphagnum. Such vegetation covers are associated with microtopographic differences, which in turn impose different soil moisture regimes. We found that litter decomposition rate and SOM composition depend much on vegetation cover. Hence, here, monitoring variations in the patchwork of vegetation seems a reliable, cost-effective way to detect climate change induced modifications to SOM and its potential to last.
C. L. Ping, J. D. Jastrow, M. T. Jorgenson, G. J. Michaelson, and Y. L. Shur
SOIL, 1, 147–171,Short summary
The huge carbon stocks found in soils of the permafrost region are important to the global climate system because of their potential to decompose and release greenhouse gases into the atmosphere upon thawing. This review highlights permafrost characteristics, the influence of cryogenic processes on soil formation, organic carbon accumulation and distribution in permafrost soils, the vulnerability of this carbon upon permafrost thaw, and the role of permafrost soils in a changing climate.
Álvaro-Fuentes, J., López, M. V., Cantero-Martinez, C., and Arrúe, J. L.: Tillage effects on soil organic carbon fractions in Mediterranean dryland agroecosystems, Soil Sci. Soc. Am. J., 72, 541–547, https://doi.org/10.2136/sssaj2007.0164, 2008.
Armas-Herrera, C. M., Dignac, M. F., Rumpel, C., Arbelo, C. D., and Chabbi, A.: Management effects on composition and dynamics of cutin and suberin in topsoil under agricultural use, Eur. J. Soil Sci., 67, 360–373, https://doi.org/10.1111/ejss.12328, 2016.
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Basile-Doelsch, I., Balesdent, J., and Rose, J.: Are Interactions between Organic Compounds and Nanoscale Weathering Minerals the Key Drivers of Carbon Storage in Soils?, Environ. Sci. Technol., 49, 3997–3998, https://doi.org/10.1021/acs.est.5b00650, 2015.
Bol, R., Poirier, N., Balesdent, J., and Gleixner, G.: Molecular turnover time of soil organic matter in particle-size fractions of an arable soil, Rapid Commun. Mass Sp., 23, 2551–2558, https://doi.org/10.1002/rcm.4124, 2009.
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Chabbi, A., Kögel-Knabner, I., and Rumpel, C.: Stabilised carbon in subsoil horizons is located in spatially distinct parts of the soil profile, Soil Biol. Biochem., 41, 256–261, https://doi.org/10.1016/j.soilbio.2008.10.033, 2009.
Chen, J., Seven, J., Zilla, T., Dippold, M. A., Blagodatskaya, E., and Kuzyakov, Y.: Microbial C : N : P stoichiometry and turnover depend on nutrients availability in soil: A 14C, 15N and 33P triple labelling study, Soil Biol. Biochem., 131, 206–216, https://doi.org/10.1016/j.soilbio.2019.01.017, 2019.
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In the context of global change, soil has been identified as a potential C sink, depending on land-use strategies. This work is devoted to identifying the processes affecting labile soil C pools resulting from changes in land use. We show that the land-use change in ley grassland provoked a decoupling of the storage and degradation processes after the grassland phase. Overall, the study enables us to develop a sufficient understanding of fine-scale C dynamics to refine soil C prediction models.
In the context of global change, soil has been identified as a potential C sink, depending on...