Articles | Volume 12, issue 22
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Reviews and syntheses: Soil resources and climate jointly drive variations in microbial biomass carbon and nitrogen in China's forest ecosystems
Z. H. Zhou
Center for Ecological Research, Northeast Forestry University, 26 Hexing Road, Harbin 150040, China
C. K. Wang
Center for Ecological Research, Northeast Forestry University, 26 Hexing Road, Harbin 150040, China
No articles found.
Jianxiao Zhu, Chuankuan Wang, Zhang Zhou, Guoyi Zhou, Xueyang Hu, Lai Jiang, Yide Li, Guohua Liu, Chengjun Ji, Shuqing Zhao, Peng Li, Jiangling Zhu, Zhiyao Tang, Chengyang Zheng, Richard A. Birdsey, Yude Pan, and Jingyun Fang
Biogeosciences, 17, 715–726,Short summary
Soil is the largest carbon pool in forests. Whether forest soils function as a sink or source of atmospheric carbon remains controversial. Here, we investigated the 20-year changes in the soil organic carbon pool at eight permanent forest plots in China. Our results revealed that the soils sequestered 3.6–16.3 % of the annual net primary production across the investigated sites, demonstrating that these forest soils have functioned as an important C sink during the past 2 decades.This article is included in the Encyclopedia of Geosciences
Related subject area
Biogeochemistry: SoilsDeforestation for agriculture leads to soil warming and enhanced litter decomposition in subarctic soilsTemperature sensitivity of soil organic carbon respiration along a forested elevation gradient in the Rwenzori Mountains, UgandaThe influence of elevated CO2 and soil depth on rhizosphere activity and nutrient availability in a mature Eucalyptus woodlandThe paradox of assessing greenhouse gases from soils for nature-based solutionsManagement-induced changes in soil organic carbon on global croplandsPore network modeling as a new tool for determining gas diffusivity in peatMapping soil organic carbon fractions for Australia, their stocks and uncertaintyTemperature sensitivity of dark CO2 fixation in temperate forest soilsEffects of precipitation seasonality, irrigation, vegetation cycle and soil type on enhanced weathering – modeling of cropland case studies across four sitesStable isotope profiles of soil organic carbon in forested and grassland landscapes in the Lake Alaotra basin (Madagascar): insights in past vegetation changesReviews and syntheses: The promise of big diverse soil data, moving current practices towards future potentialDynamics of rare earth elements and associated major and trace elements during Douglas-fir (Pseudotsuga menziesii) and European beech (Fagus sylvatica L.) litter degradationTo what extent can soil moisture and soil Cu contamination stresses affect nitrous species emissions? Estimation through calibration of a nitrification–denitrification modelCarbon, nitrogen, and phosphorus stoichiometry of organic matter in Swedish forest soils and its relationship with climate, tree species, and soil textureSoil geochemistry as a driver of soil organic matter composition: insights from a soil chronosequenceLeaching of inorganic and organic phosphorus and nitrogen in contrasting beech forest soils – seasonal patterns and effects of fertilizationAge and chemistry of dissolved organic carbon reveal enhanced leaching of ancient labile carbon at the permafrost thaw zoneSoil organic carbon stabilization mechanisms and temperature sensitivity in old terraced soilsEffect of organic carbon addition on paddy soil organic carbon decomposition under different irrigation regimesSoil profile connectivity can impact microbial substrate use, affecting how soil CO2 effluxes are controlled by temperatureAdditional carbon inputs to reach a 4 per 1000 objective in Europe: feasibility and projected impacts of climate change based on Century simulations of long-term arable experimentsCycling and retention of nitrogen in European beech (Fagus sylvatica L.) ecosystems under elevated fructification frequencyMercury mobility, colloid formation and methylation in a polluted Fluvisol as affected by manure application and flooding–draining cycleSimulating measurable ecosystem carbon and nitrogen dynamics with the mechanistically defined MEMS 2.0 modelSimilar importance of edaphic and climatic factors for controlling soil organic carbon stocks of the worldRepresenting methane emissions from wet tropical forest soils using microbial functional groups constrained by soil diffusivityLong-term bare-fallow soil fractions reveal thermo-chemical properties controlling soil organic carbon dynamicsGeochemical zones and environmental gradients for soils from the central Transantarctic Mountains, AntarcticaAge distribution, extractability, and stability of mineral-bound organic carbon in central European soilsDenitrification in soil as a function of oxygen availability at the microscaleKey drivers of pyrogenic carbon redistribution during a simulated rainfall eventSubsurface flow and phosphorus dynamics in beech forest hillslopes during sprinkling experiments: how fast is phosphorus replenished?Estimating maximum fine-fraction organic carbon in UK grasslandsMillennial-age glycerol dialkyl glycerol tetraethers (GDGTs) in forested mineral soils: 14C-based evidence for stabilization of microbial necromassParticles under stress: ultrasonication causes size and recovery rate artifacts with soil-derived POM but not with microplasticsDeepening roots can enhance carbonate weathering by amplifying CO2-rich rechargeVertical mobility of pyrogenic organic matter in soils: a column experimentVertical partitioning of CO2 production in a forest soilInteractions between biogeochemical and management factors explain soil organic carbon in Pyrenean grasslandsReviews and syntheses: Ironing out wrinkles in the soil phosphorus cycling paradigmHerbicide weed control increases nutrient leaching compared to mechanical weeding in a large-scale oil palm plantationReviews and syntheses: The mechanisms underlying carbon storage in soilIdentification of lower-order inositol phosphates (IP5 and IP4) in soil extracts as determined by hypobromite oxidation and solution 31P NMR spectroscopyModelling dynamic interactions between soil structure and the storage and turnover of soil organic matterWarming increases soil respiration in a carbon-rich soil without changing microbial respiratory potentialReviews and syntheses: Soil responses to manipulated precipitation changes – an assessment of meta-analysesFrom fibrous plant residues to mineral-associated organic carbon – the fate of organic matter in Arctic permafrost soilsRelevance of aboveground litter for soil organic matter formation – a soil profile perspectiveA revised pan-Arctic permafrost soil Hg pool based on Western Siberian peat Hg and carbon observationsUsing respiration quotients to track changing sources of soil respiration seasonally and with experimental warming
Tino Peplau, Christopher Poeplau, Edward Gregorich, and Julia Schroeder
Biogeosciences, 20, 1063–1074,Short summary
We buried tea bags and temperature loggers in a paired-plot design in soils under forest and agricultural land and retrieved them after 2 years to quantify the effect of land-use change on soil temperature and litter decomposition in subarctic agricultural systems. We could show that agricultural soils were on average 2 °C warmer than forests and that litter decomposition was enhanced. The results imply that deforestation amplifies effects of climate change on soil organic matter dynamics.This article is included in the Encyclopedia of Geosciences
Joseph Okello, Marijn Bauters, Hans Verbeeck, Samuel Bodé, John Kasenene, Astrid Françoys, Till Engelhardt, Klaus Butterbach-Bahl, Ralf Kiese, and Pascal Boeckx
Biogeosciences, 20, 719–735,Short summary
The increase in global and regional temperatures has the potential to drive accelerated soil organic carbon losses in tropical forests. We simulated climate warming by translocating intact soil cores from higher to lower elevations. The results revealed increasing temperature sensitivity and decreasing losses of soil organic carbon with increasing elevation. Our results suggest that climate warming may trigger enhanced losses of soil organic carbon from tropical montane forests.This article is included in the Encyclopedia of Geosciences
Johanna Pihlblad, Louise C. Andresen, Catriona A. Macdonald, David S. Ellsworth, and Yolima Carrillo
Biogeosciences, 20, 505–521,Short summary
Elevated CO2 in the atmosphere increases forest biomass productivity when growth is not limited by soil nutrients. This study explores how mature trees stimulate soil availability of nitrogen and phosphorus with free-air carbon dioxide enrichment after 5 years of fumigation. We found that both nutrient availability and processes feeding available pools increased in the rhizosphere, and phosphorus increased at depth. This appears to not be by decomposition but by faster recycling of nutrients.This article is included in the Encyclopedia of Geosciences
Rodrigo Vargas and Van Huong Le
Biogeosciences, 20, 15–26,Short summary
Quantifying the role of soils in nature-based solutions requires accurate estimates of soil greenhouse gas (GHG) fluxes. We suggest that multiple GHG fluxes should not be simultaneously measured at a few fixed time intervals, but an optimized sampling approach can reduce bias and uncertainty. Our results have implications for assessing GHG fluxes from soils and a better understanding of the role of soils in nature-based solutions.This article is included in the Encyclopedia of Geosciences
Kristine Karstens, Benjamin Leon Bodirsky, Jan Philipp Dietrich, Marta Dondini, Jens Heinke, Matthias Kuhnert, Christoph Müller, Susanne Rolinski, Pete Smith, Isabelle Weindl, Hermann Lotze-Campen, and Alexander Popp
Biogeosciences, 19, 5125–5149,Short summary
Soil organic carbon (SOC) has been depleted by anthropogenic land cover change and agricultural management. While SOC models often simulate detailed biochemical processes, the management decisions are still little investigated at the global scale. We estimate that soils have lost around 26 GtC relative to a counterfactual natural state in 1975. Yet, since 1975, SOC has been increasing again by 4 GtC due to a higher productivity, recycling of crop residues and manure, and no-tillage practices.This article is included in the Encyclopedia of Geosciences
Petri Kiuru, Marjo Palviainen, Arianna Marchionne, Tiia Grönholm, Maarit Raivonen, Lukas Kohl, and Annamari Laurén
Biogeosciences, 19, 5041–5058,Short summary
Peatlands are large carbon stocks. Emissions of carbon dioxide and methane from peatlands may increase due to changes in management and climate. We studied the variation in the gas diffusivity of peat with depth using pore network simulations and laboratory experiments. Gas diffusivity was found to be lower in deeper peat with smaller pores and lower pore connectivity. However, gas diffusivity was not extremely low in wet conditions, which may reflect the distinctive structure of peat.This article is included in the Encyclopedia of Geosciences
Mercedes Román Dobarco, Alexandre M. J-C. Wadoux, Brendan Malone, Budiman Minasny, Alex B. McBratney, and Ross Searle
Revised manuscript accepted for BGShort summary
Soil organic carbon (SOC) is has an heterogeneous nature and varies in chemistry, stabilization mechanisms and persistence in soil. In this study we mapped the stocks of SOC fractions with different characteristics and turnover rate (presumably PyOC >= MAOC > POC) across Australia, combining spectroscopy and digital soil mapping. The SOC stocks (0–30 cm) were estimated as 12.7 Pg MAOC, 2 Pg POC and 5.1 Pg PyOC.This article is included in the Encyclopedia of Geosciences
Rachael Akinyede, Martin Taubert, Marion Schrumpf, Susan Trumbore, and Kirsten Küsel
Biogeosciences, 19, 4011–4028,Short summary
Soils will likely become warmer in the future, and this can increase the release of carbon dioxide (CO2) into the atmosphere. As microbes can take up soil CO2 and prevent further escape into the atmosphere, this study compares the rate of uptake and release of CO2 at two different temperatures. With warming, the rate of CO2 uptake increases less than the rate of release, indicating that the capacity to modulate soil CO2 release into the atmosphere will decrease under future warming.This article is included in the Encyclopedia of Geosciences
Giuseppe Cipolla, Salvatore Calabrese, Amilcare Porporato, and Leonardo V. Noto
Biogeosciences, 19, 3877–3896,Short summary
Enhanced weathering (EW) is a promising strategy for carbon sequestration. Since models may help to characterize field EW, the present work applies a hydro-biogeochemical model to four case studies characterized by different rainfall seasonality, vegetation and soil type. Rainfall seasonality strongly affects EW dynamics, but low carbon sequestration suggests that an in-depth analysis at the global scale is required to see if EW may be effective to mitigate climate change.This article is included in the Encyclopedia of Geosciences
Vao Fenotiana Razanamahandry, Marjolein Dewaele, Gerard Govers, Liesa Brosens, Benjamin Campforts, Liesbet Jacobs, Tantely Razafimbelo, Tovonarivo Rafolisy, and Steven Bouillon
Biogeosciences, 19, 3825–3841,Short summary
In order to shed light on possible past vegetation shifts in the Central Highlands of Madagascar, we measured stable isotope ratios of organic carbon in soil profiles along both forested and grassland hillslope transects in the Lake Alaotra region. Our results show that the landscape of this region was more forested in the past: soils in the C4-dominated grasslands contained a substantial fraction of C3-derived carbon, increasing with depth.This article is included in the Encyclopedia of Geosciences
Katherine E. O. Todd-Brown, Rose Z. Abramoff, Jeffrey Beem-Miller, Hava K. Blair, Stevan Earl, Kristen J. Frederick, Daniel R. Fuka, Mario Guevara Santamaria, Jennifer W. Harden, Katherine Heckman, Lillian J. Heran, James R. Holmquist, Alison M. Hoyt, David H. Klinges, David S. LeBauer, Avni Malhotra, Shelby C. McClelland, Lucas E. Nave, Katherine S. Rocci, Sean M. Schaeffer, Shane Stoner, Natasja van Gestel, Sophie F. von Fromm, and Marisa L. Younger
Biogeosciences, 19, 3505–3522,Short summary
Research data are becoming increasingly available online with tantalizing possibilities for reanalysis. However harmonizing data from different sources remains challenging. Using the soils community as an example, we walked through the various strategies that researchers currently use to integrate datasets for reanalysis. We find that manual data transcription is still extremely common and that there is a critical need for community-supported informatics tools like vocabularies and ontologies.This article is included in the Encyclopedia of Geosciences
Alessandro Montemagno, Christophe Hissler, Victor Bense, Adriaan J. Teuling, Johanna Ziebel, and Laurent Pfister
Biogeosciences, 19, 3111–3129,Short summary
We investigated the biogeochemical processes that dominate the release and retention of elements (nutrients and potentially toxic elements) during litter degradation. Our results show that toxic elements are retained in the litter, while nutrients are released in solution during the first stages of degradation. This seems linked to the capability of trees to distribute the elements between degradation-resistant and non-degradation-resistant compounds of leaves according to their chemical nature.This article is included in the Encyclopedia of Geosciences
Laura Sereni, Bertrand Guenet, Charlotte Blasi, Olivier Crouzet, Jean-Christophe Lata, and Isabelle Lamy
Biogeosciences, 19, 2953–2968,Short summary
This study focused on the modellisation of two important drivers of soil greenhouse gas emissions: soil contamination and soil moisture change. The aim was to include a Cu function in the soil biogeochemical model DNDC for different soil moisture conditions and then to estimate variation in N2O, NO2 or NOx emissions. Our results show a larger effect of Cu on N2 and N2O emissions than on the other nitrogen species and a higher effect for the soils incubated under constant constant moisture.This article is included in the Encyclopedia of Geosciences
Marie Spohn and Johan Stendahl
Biogeosciences, 19, 2171–2186,Short summary
We explored the ratios of carbon (C), nitrogen (N), and phosphorus (P) of organic matter in Swedish forest soils. The N : P ratio of the organic layer was most strongly related to the mean annual temperature, while the C : N ratios of the organic layer and mineral soil were strongly related to tree species even in the subsoil. The organic P concentration in the mineral soil was strongly affected by soil texture, which diminished the effect of tree species on the C to organic P (C : OP) ratio.This article is included in the Encyclopedia of Geosciences
Moritz Mainka, Laura Summerauer, Daniel Wasner, Gina Garland, Marco Griepentrog, Asmeret Asefaw Berhe, and Sebastian Doetterl
Biogeosciences, 19, 1675–1689,Short summary
The largest share of terrestrial carbon is stored in soils, making them highly relevant as regards global change. Yet, the mechanisms governing soil carbon stabilization are not well understood. The present study contributes to a better understanding of these processes. We show that qualitative changes in soil organic matter (SOM) co-vary with alterations of the soil matrix following soil weathering. Hence, the type of SOM that is stabilized in soils might change as soils develop.This article is included in the Encyclopedia of Geosciences
Jasmin Fetzer, Emmanuel Frossard, Klaus Kaiser, and Frank Hagedorn
Biogeosciences, 19, 1527–1546,Short summary
As leaching is a major pathway of nitrogen and phosphorus loss in forest soils, we investigated several potential drivers in two contrasting beech forests. The composition of leachates, obtained by zero-tension lysimeters, varied by season, and climatic extremes influenced the magnitude of leaching. Effects of nitrogen and phosphorus fertilization varied with soil nutrient status and sorption properties, and leaching from the low-nutrient soil was more sensitive to environmental factors.This article is included in the Encyclopedia of Geosciences
Karis J. McFarlane, Heather M. Throckmorton, Jeffrey M. Heikoop, Brent D. Newman, Alexandra L. Hedgpeth, Marisa N. Repasch, Thomas P. Guilderson, and Cathy J. Wilson
Biogeosciences, 19, 1211–1223,Short summary
Planetary warming is increasing seasonal thaw of permafrost, making this extensive old carbon stock vulnerable. In northern Alaska, we found more and older dissolved organic carbon in small drainages later in summer as more permafrost was exposed by deepening thaw. Younger and older carbon did not differ in chemical indicators related to biological lability suggesting this carbon can cycle through aquatic systems and contribute to greenhouse gas emissions as warming increases permafrost thaw.This article is included in the Encyclopedia of Geosciences
Pengzhi Zhao, Daniel Joseph Fallu, Sara Cucchiaro, Paolo Tarolli, Clive Waddington, David Cockcroft, Lisa Snape, Andreas Lang, Sebastian Doetterl, Antony G. Brown, and Kristof Van Oost
Biogeosciences, 18, 6301–6312,Short summary
We investigate the factors controlling the soil organic carbon (SOC) stability and temperature sensitivity of abandoned prehistoric agricultural terrace soils. Results suggest that the burial of former topsoil due to terracing provided an SOC stabilization mechanism. Both the soil C : N ratio and SOC mineral protection regulate soil SOC temperature sensitivity. However, which mechanism predominantly controls SOC temperature sensitivity depends on the age of the buried terrace soils.This article is included in the Encyclopedia of Geosciences
Heleen Deroo, Masuda Akter, Samuel Bodé, Orly Mendoza, Haichao Li, Pascal Boeckx, and Steven Sleutel
Biogeosciences, 18, 5035–5051,Short summary
We assessed if and how incorporation of exogenous organic carbon (OC) such as straw could affect decomposition of native soil organic carbon (SOC) under different irrigation regimes. Addition of exogenous OC promoted dissolution of native SOC, partly because of increased Fe reduction, leading to more net release of Fe-bound SOC. Yet, there was no proportionate priming of SOC-derived DOC mineralisation. Water-saving irrigation can retard both priming of SOC dissolution and mineralisation.This article is included in the Encyclopedia of Geosciences
Frances A. Podrebarac, Sharon A. Billings, Kate A. Edwards, Jérôme Laganière, Matthew J. Norwood, and Susan E. Ziegler
Biogeosciences, 18, 4755–4772,Short summary
Soil respiration is a large and temperature-responsive flux in the global carbon cycle. We found increases in microbial use of easy to degrade substrates enhanced the temperature response of respiration in soils layered as they are in situ. This enhanced response is consistent with soil composition differences in warm relative to cold climate forests. These results highlight the importance of the intact nature of soils rarely studied in regulating responses of CO2 fluxes to changing temperature.This article is included in the Encyclopedia of Geosciences
Elisa Bruni, Bertrand Guenet, Yuanyuan Huang, Hugues Clivot, Iñigo Virto, Roberta Farina, Thomas Kätterer, Philippe Ciais, Manuel Martin, and Claire Chenu
Biogeosciences, 18, 3981–4004,Short summary
Increasing soil organic carbon (SOC) stocks is beneficial for climate change mitigation and food security. One way to enhance SOC stocks is to increase carbon input to the soil. We estimate the amount of carbon input required to reach a 4 % annual increase in SOC stocks in 14 long-term agricultural experiments around Europe. We found that annual carbon input should increase by 43 % under current temperature conditions, by 54 % for a 1 °C warming scenario and by 120 % for a 5 °C warming scenario.This article is included in the Encyclopedia of Geosciences
Rainer Brumme, Bernd Ahrends, Joachim Block, Christoph Schulz, Henning Meesenburg, Uwe Klinck, Markus Wagner, and Partap K. Khanna
Biogeosciences, 18, 3763–3779,Short summary
In order to study the fate of litter nitrogen in forest soils, we combined a leaf litterfall exchange experiment using 15N-labeled leaf litter with long-term element budgets at seven European beech sites in Germany. It appears that fructification intensity, which has increased in recent decades, has a distinct impact on N retention in forest soils. Despite reduced nitrogen deposition, about 6 and 10 kg ha−1 of nitrogen were retained annually in the soils and in the forest stands, respectively.This article is included in the Encyclopedia of Geosciences
Lorenz Gfeller, Andrea Weber, Isabelle Worms, Vera I. Slaveykova, and Adrien Mestrot
Biogeosciences, 18, 3445–3465,Short summary
Our incubation experiment shows that flooding of polluted floodplain soils may induce pulses of both mercury (Hg) and methylmercury to the soil solution and threaten downstream ecosystems. We demonstrate that mobilization of Hg bound to manganese oxides is a relevant process in organic-matter-poor soils. Addition of organic amendments accelerates this mobilization but also facilitates the formation of nanoparticulate Hg and the subsequent fixation of Hg from soil solution to the soil.This article is included in the Encyclopedia of Geosciences
Yao Zhang, Jocelyn M. Lavallee, Andy D. Robertson, Rebecca Even, Stephen M. Ogle, Keith Paustian, and M. Francesca Cotrufo
Biogeosciences, 18, 3147–3171,Short summary
Soil organic matter (SOM) is essential for the health of soils, and the accumulation of SOM helps removal of CO2 from the atmosphere. Here we present the result of the continued development of a mathematical model that simulates SOM and its measurable fractions. In this study, we simulated several grassland sites in the US, and the model generally captured the carbon and nitrogen amounts in SOM and their distribution between the measurable fractions throughout the entire soil profile.This article is included in the Encyclopedia of Geosciences
Zhongkui Luo, Raphael A. Viscarra-Rossel, and Tian Qian
Biogeosciences, 18, 2063–2073,Short summary
Using the data from 141 584 whole-soil profiles across the globe, we disentangled the relative importance of biotic, climatic and edaphic variables in controlling global SOC stocks. The results suggested that soil properties and climate contributed similarly to the explained global variance of SOC in four sequential soil layers down to 2 m. However, the most important individual controls are consistently soil-related, challenging current climate-driven framework of SOC dynamics.This article is included in the Encyclopedia of Geosciences
Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, and Melanie A. Mayes
Biogeosciences, 18, 1769–1786,Short summary
Humid tropical soils are important sources and sinks of methane. We used model simulation to understand how different kinds of microbes and observed soil moisture and oxygen dynamics contribute to production and consumption of methane along a wet tropical hillslope during normal and drought conditions. Drought alters the diffusion of oxygen and microbial substrates into and out of soil microsites, resulting in enhanced methane release from the entire hillslope during drought recovery.This article is included in the Encyclopedia of Geosciences
Mathieu Chassé, Suzanne Lutfalla, Lauric Cécillon, François Baudin, Samuel Abiven, Claire Chenu, and Pierre Barré
Biogeosciences, 18, 1703–1718,Short summary
Evolution of organic carbon content in soils could be a major driver of atmospheric greenhouse gas concentrations over the next century. Understanding factors controlling carbon persistence in soil is a challenge. Our study of unique long-term bare-fallow samples, depleted in labile organic carbon, helps improve the separation, evaluation and characterization of carbon pools with distinct residence time in soils and gives insight into the mechanisms explaining soil organic carbon persistence.This article is included in the Encyclopedia of Geosciences
Melisa A. Diaz, Christopher B. Gardner, Susan A. Welch, W. Andrew Jackson, Byron J. Adams, Diana H. Wall, Ian D. Hogg, Noah Fierer, and W. Berry Lyons
Biogeosciences, 18, 1629–1644,Short summary
Water-soluble salt and nutrient concentrations of soils collected along the Shackleton Glacier, Antarctica, show distinct geochemical gradients related to latitude, longitude, elevation, soil moisture, and distance from coast and glacier. Machine learning algorithms were used to estimate geochemical gradients for the region given the relationship with geography. Geography and surface exposure age drive salt and nutrient abundances, influencing invertebrate habitat suitability and biogeography.This article is included in the Encyclopedia of Geosciences
Marion Schrumpf, Klaus Kaiser, Allegra Mayer, Günter Hempel, and Susan Trumbore
Biogeosciences, 18, 1241–1257,Short summary
A large amount of organic carbon (OC) in soil is protected against decay by bonding to minerals. We studied the release of mineral-bonded OC by NaF–NaOH extraction and H2O2 oxidation. Unexpectedly, extraction and oxidation removed mineral-bonded OC at roughly constant portions and of similar age distributions, irrespective of mineral composition, land use, and soil depth. The results suggest uniform modes of interactions between OC and minerals across soils in quasi-steady state with inputs.This article is included in the Encyclopedia of Geosciences
Lena Rohe, Bernd Apelt, Hans-Jörg Vogel, Reinhard Well, Gi-Mick Wu, and Steffen Schlüter
Biogeosciences, 18, 1185–1201,Short summary
Total denitrification, i.e. N2O and (N2O + N2) fluxes, of repacked soil cores were analysed for different combinations of soils and water contents. Prediction accuracy of (N2O + N2) fluxes was highest with combined proxies for oxygen demand (CO2 flux) and oxygen supply (anaerobic soil volume fraction). Knowledge of denitrification completeness (product ratio) improved N2O predictions. Substitutions with cheaper proxies (soil organic matter, empirical diffusivity) reduced prediction accuracy.This article is included in the Encyclopedia of Geosciences
Severin-Luca Bellè, Asmeret Asefaw Berhe, Frank Hagedorn, Cristina Santin, Marcus Schiedung, Ilja van Meerveld, and Samuel Abiven
Biogeosciences, 18, 1105–1126,Short summary
Controls of pyrogenic carbon (PyC) redistribution under rainfall are largely unknown. However, PyC mobility can be substantial after initial rain in post-fire landscapes. We conducted a controlled simulation experiment on plots where PyC was applied on the soil surface. We identified redistribution of PyC by runoff and splash and vertical movement in the soil depending on soil texture and PyC characteristics (material and size). PyC also induced changes in exports of native soil organic carbon.This article is included in the Encyclopedia of Geosciences
Michael Rinderer, Jaane Krüger, Friederike Lang, Heike Puhlmann, and Markus Weiler
Biogeosciences, 18, 1009–1027,Short summary
We quantified the lateral and vertical subsurface flow (SSF) and P concentrations of three beech forest plots with contrasting soil properties during sprinkling experiments. Vertical SSF was 2 orders of magnitude larger than lateral SSF, and both consisted mainly of pre-event water. P concentrations in SSF were high during the first 1 to 2 h (nutrient flushing) but nearly constant thereafter. This suggests that P in the soil solution was replenished fast by mineral or organic sources.This article is included in the Encyclopedia of Geosciences
Kirsty C. Paterson, Joanna M. Cloy, Robert M. Rees, Elizabeth M. Baggs, Hugh Martineau, Dario Fornara, Andrew J. Macdonald, and Sarah Buckingham
Biogeosciences, 18, 605–620,Short summary
Soil organic carbon sequestration across agroecosystems worldwide can contribute to mitigating the effects of climate change by reducing levels of atmospheric carbon dioxide. The maximum carbon sequestration potential is frequently estimated using the linear regression equation developed by Hassink (1997). This work examines the suitability of this equation for use in grasslands across the United Kingdom. The results highlight the need to ensure the fit of equations to the soils being studied.This article is included in the Encyclopedia of Geosciences
Hannah Gies, Frank Hagedorn, Maarten Lupker, Daniel Montluçon, Negar Haghipour, Tessa Sophia van der Voort, and Timothy Ian Eglinton
Biogeosciences, 18, 189–205,Short summary
Understanding controls on the persistence of organic matter in soils is essential to constrain its role in the carbon cycle. Emerging concepts suggest that the soil carbon pool is predominantly comprised of stabilized microbial residues. To test this hypothesis we isolated microbial membrane lipids from two Swiss soil profiles and measured their radiocarbon age. We find that the ages of these compounds are in the range of millenia and thus provide evidence for stabilized microbial mass in soils.This article is included in the Encyclopedia of Geosciences
Frederick Büks, Gilles Kayser, Antonia Zieger, Friederike Lang, and Martin Kaupenjohann
Biogeosciences, 18, 159–167,Short summary
Ultrasonication/density fractionation is a common method used to extract particulate organic matter (POM) and, recently, microplastic (MP) from soil samples. In this study, ultrasonic treatment with mechanical stress increasing from 0 to 500 J mL−1 caused comminution and a reduced recovery rate of soil-derived POMs but no such effects with MP particles. In consequence, the extraction of MP from soils is not affected by particle size and recovery rate artifacts.This article is included in the Encyclopedia of Geosciences
Hang Wen, Pamela L. Sullivan, Gwendolyn L. Macpherson, Sharon A. Billings, and Li Li
Biogeosciences, 18, 55–75,Short summary
Carbonate weathering is essential in regulating carbon cycle at the century timescale. Plant roots accelerate weathering by elevating soil CO2 via respiration. It however remains poorly understood how and how much rooting characteristics modify flow paths and weathering. This work indicates that deepening roots in woodlands can enhance carbonate weathering by promoting recharge and CO2–carbonate contact in the deep, carbonate-abundant subsurface.This article is included in the Encyclopedia of Geosciences
Marcus Schiedung, Severin-Luca Bellè, Gabriel Sigmund, Karsten Kalbitz, and Samuel Abiven
Biogeosciences, 17, 6457–6474,Short summary
The mobility of pyrogenic organic matter (PyOM) in soils is largely unknow, while it is a major and persistent component of the soil organic matter. With a soil column experiment, we identified that only a small proportion of PyOM can migrate through the soil, but its export is continuous. Aging and associated oxidation increase its mobility but also its retention in soils. Further, PyOM can alter the vertical mobility of native soil organic carbon during its downward migration.This article is included in the Encyclopedia of Geosciences
Patrick Wordell-Dietrich, Anja Wotte, Janet Rethemeyer, Jörg Bachmann, Mirjam Helfrich, Kristina Kirfel, Christoph Leuschner, and Axel Don
Biogeosciences, 17, 6341–6356,Short summary
The release of CO2 from soils, known as soil respiration, plays a major role in the global carbon cycle. However, the contributions of different soil depths or the sources of soil CO2 have hardly been studied. We quantified the CO2 production for different soil layers (up to 1.5 m) in three soil profiles for 2 years. We found that 90 % of CO2 production occurs in the first 30 cm of the soil profile, and that the CO2 originated from young carbon sources, as revealed by radiocarbon measurements.This article is included in the Encyclopedia of Geosciences
Antonio Rodríguez, Rosa Maria Canals, Josefina Plaixats, Elena Albanell, Haifa Debouk, Jordi Garcia-Pausas, Leticia San Emeterio, Àngela Ribas, Juan José Jimenez, and M.-Teresa Sebastià
Biogeosciences, 17, 6033–6050,Short summary
The novelty of our work is that it presents a series of potential interactions between drivers of soil organic carbon at broad scales in temperate mountain grasslands. The most relevant contribution of our work is that it illustrates the importance of grazing management for soil carbon stocks, indicating that interactions between grazing species and soil nitrogen and herbage quality may be promising paths in order to design further management policies for palliating climate change.This article is included in the Encyclopedia of Geosciences
Curt A. McConnell, Jason P. Kaye, and Armen R. Kemanian
Biogeosciences, 17, 5309–5333,Short summary
Soil phosphorus (P) management is a critical challenge for agriculture worldwide; yet, simulation models of soil P processes lag those of other essential nutrients. In this review, we identify hindrances to measuring and modeling soil P pools and fluxes. We highlight the need to clarify biological and mineral interactions by defining P pools explicitly and using evolving techniques, such as tracing P in phosphates using oxygen isotopes.This article is included in the Encyclopedia of Geosciences
Greta Formaglio, Edzo Veldkamp, Xiaohong Duan, Aiyen Tjoa, and Marife D. Corre
Biogeosciences, 17, 5243–5262,Short summary
The intensive management of large-scale oil palm plantations may result in high nutrient leaching losses which reduce soil fertility and potentially pollute water bodies. The reduction in management intensity with lower fertilization rates and with mechanical weeding instead of the use of herbicide results in lower nutrient leaching losses while maintaining high yield. Lower leaching results from lower nutrient inputs from fertilizer and from higher retention by enhanced cover vegetation.This article is included in the Encyclopedia of Geosciences
Isabelle Basile-Doelsch, Jérôme Balesdent, and Sylvain Pellerin
Biogeosciences, 17, 5223–5242,Short summary
The 4 per 1000 initiative aims to restore carbon storage in soils to both mitigate climate change and contribute to food security. The French National Institute for Agricultural Research conducted a study to determine the carbon storage potential in French soils and associated costs. This paper is a part of that study. It reviews recent advances concerning the mechanisms that controls C stabilization in soils. Synthetic figures integrating new concepts should be of pedagogical interest.This article is included in the Encyclopedia of Geosciences
Jolanda E. Reusser, René Verel, Daniel Zindel, Emmanuel Frossard, and Timothy I. McLaren
Biogeosciences, 17, 5079–5095,Short summary
Inositol phosphates (IPs) are a major pool of organic P in soil. However, information on their diversity and abundance in soil is limited. We isolated IPs from soil and characterised them using solution nuclear magnetic resonance (NMR) spectroscopy. For the first time, we provide direct spectroscopic evidence for the existence of a multitude of lower-order IPs in soil extracts previously not detected with NMR. Our findings will help provide new insight into the cycling of IPs in ecosystems.This article is included in the Encyclopedia of Geosciences
Katharina Hildegard Elisabeth Meurer, Claire Chenu, Elsa Coucheney, Anke Marianne Herrmann, Thomas Keller, Thomas Kätterer, David Nimblad Svensson, and Nicholas Jarvis
Biogeosciences, 17, 5025–5042,Short summary
We present a simple model that describes, for the first time, the dynamic two-way interactions between soil organic matter and soil physical properties (porosity, pore size distribution, bulk density and layer thickness). The model was able to accurately reproduce the changes in soil organic carbon, soil bulk density and surface elevation observed during 63 years in a field trial, as well as soil water retention curves measured at the end of the experimental period.This article is included in the Encyclopedia of Geosciences
Marion Nyberg and Mark J. Hovenden
Biogeosciences, 17, 4405–4420,Short summary
Experimental warming increased soil respiration (RS) by more than 25 % in a Tasmanian C-rich soil, but there was no impact on microbial respiration in laboratory experiments. Plant community composition had no effect on RS, suggesting the response is likely due to enhanced belowground plant respiration and C supply through rhizodeposition and root exudates. Results imply we need studies of both C inputs and losses to model net ecosystem C exchange of these crucial, C-dense systems effectively.This article is included in the Encyclopedia of Geosciences
Akane O. Abbasi, Alejandro Salazar, Youmi Oh, Sabine Reinsch, Maria del Rosario Uribe, Jianghanyang Li, Irfan Rashid, and Jeffrey S. Dukes
Biogeosciences, 17, 3859–3873,Short summary
In this study, we provide a holistic view of soil responses to precipitation changes. A total of 16 meta-analyses focusing on the effects of precipitation changes on 42 soil response variables were compared. A strong agreement was found that the belowground carbon and nitrogen cycling accelerate under increased precipitation and slow under decreased precipitation, while bacterial and fungal communities are relatively resistant to decreased precipitation. Knowledge gaps were also identified.This article is included in the Encyclopedia of Geosciences
Isabel Prater, Sebastian Zubrzycki, Franz Buegger, Lena C. Zoor-Füllgraff, Gerrit Angst, Michael Dannenmann, and Carsten W. Mueller
Biogeosciences, 17, 3367–3383,Short summary
Large amounts of soil organic matter stored in permafrost-affected soils from Arctic Russia are present as undecomposed plant residues. This large fibrous organic matter might be highly vulnerable to microbial decay, while small mineral-associated organic matter can most probably attenuate carbon mineralization in a warmer future. Labile soil fractions also store large amounts of nitrogen, which might be lost during permafrost collapse while fostering the decomposition of soil organic matter.This article is included in the Encyclopedia of Geosciences
Patrick Liebmann, Patrick Wordell-Dietrich, Karsten Kalbitz, Robert Mikutta, Fabian Kalks, Axel Don, Susanne K. Woche, Leena R. Dsilva, and Georg Guggenberger
Biogeosciences, 17, 3099–3113,Short summary
We studied the contribution of litter-derived carbon (C) in the formation of subsoil organic matter (OM). Soil core sampling, 13C field labeling, density fractionation, and water extractions were used to track its contribution to different functional OM fractions down to the deep subsoil. We show that while migrating down the soil profile, OM undergoes a sequence of repeated sorption, microbial processing, and desorption. However, the contribution of litter-derived C to subsoil OM is small.This article is included in the Encyclopedia of Geosciences
Artem G. Lim, Martin Jiskra, Jeroen E. Sonke, Sergey V. Loiko, Natalia Kosykh, and Oleg S. Pokrovsky
Biogeosciences, 17, 3083–3097,Short summary
To better understand the mercury (Hg) content in northern soils, we measured Hg concentration in peat cores across a 1700 km permafrost gradient in Siberia. We demonstrated a northward increase in Hg concentration in peat and Hg pools in frozen peatlands. We revised the 0–30 cm northern soil Hg pool to be 72 Gg, which is 7 % of the global soil Hg pool of 1086 Gg. The results are important for understanding Hg exchange between soil, water, and the atmosphere under climate change in the Arctic.This article is included in the Encyclopedia of Geosciences
Caitlin Hicks Pries, Alon Angert, Cristina Castanha, Boaz Hilman, and Margaret S. Torn
Biogeosciences, 17, 3045–3055,Short summary
The apparent respiration quotient (ARQ) changes according to which substrates microbes consume, allowing sources of soil respiration to be traced. In a forest soil warming experiment, ARQ had a strong seasonal pattern that reflected a shift from respiration being fueled by sugars and organic acids derived from roots during the growing season to respiration being fueled by dead microbes during winter. ARQ values also changed with experimental warming.This article is included in the Encyclopedia of Geosciences
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Soil microbial biomass carbon (Cmic) and nitrogen (Nmic) and microbial quotient varied substantially across China’s forest ecosystems (CV 61–96%). Soil resources and climate together explained 24–41% of the variations. Cmic:Nmic ratio declined slightly with soil C:N ratio and changed with latitude and climate, suggesting a plastic homeostasis of microbial C-N stoichiometry. Divergent responses of microbial quotient of C and N to environment imply different mechanisms regulating Cmic and Nmic.
Soil microbial biomass carbon (Cmic) and nitrogen (Nmic) and microbial quotient varied...