Articles | Volume 14, issue 14
Research article 21 Jul 2017
Research article | 21 Jul 2017
Boreal coniferous forest density leads to significant variations in soil physical and geochemical properties
Carole Bastianelli et al.
No articles found.
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.
Emeline Chaste, Martin P. Girardin, Jed O. Kaplan, Jeanne Portier, Yves Bergeron, and Christelle Hély
Biogeosciences, 15, 1273–1292,Short summary
A vegetation model was used to reconstruct fire activity from 1901 to 2012 in relation to changes in lightning ignition, climate, and vegetation in eastern Canada's boreal forest. The model correctly simulated the history of fire activity. The results showed that fire activity is ignition limited but is also greatly affected by both climate and vegetation. This research aims to develop a vegetation model that could be used to predict the future impacts of climate changes on fire activity.
T. T. van Leeuwen, G. R. van der Werf, A. A. Hoffmann, R. G. Detmers, G. Rücker, N. H. F. French, S. Archibald, J. A. Carvalho Jr., G. D. Cook, W. J. de Groot, C. Hély, E. S. Kasischke, S. Kloster, J. L. McCarty, M. L. Pettinari, P. Savadogo, E. C. Alvarado, L. Boschetti, S. Manuri, C. P. Meyer, F. Siegert, L. A. Trollope, and W. S. W. Trollope
Biogeosciences, 11, 7305–7329,
C. Hély, A.-M. Lézine, and APD contributors
Clim. Past, 10, 681–686,
Related subject area
Biogeochemistry: SoilsEstimating 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 plantationKey drivers of pyrogenic carbon redistribution during a simulated rainfall eventReviews and syntheses: The mechanisms underlying carbon storage in soilLong-term bare fallow soil fractions reveal thermo-chemical properties controlling soil organic carbon dynamicsIdentification 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 matterGeochemical zones and environmental gradients for soils from the Central Transantarctic Mountains, AntarcticaWarming 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-analysesRepresenting methane emissions from wet tropical forest soils using microbial functional groups constrained by soil diffusivityDenitrification in soil as a function of oxygen supply and demand at the microscaleAge distribution, extractability, and stability of mineral-bound organic carbon in central European soilsFrom 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 warmingThe soil organic carbon stabilization potential of old and new wheat cultivars: a 13CO2-labeling studyPhosphorus Transport in Subsurface Flow at Beech Forest Stands: Does Phosphorus Mobilization Keep up with Transport?Drivers and modelling of blue carbon stock variability in sediments of southeastern AustraliaA comparison of patterns of microbial C : N : P stoichiometry between topsoil and subsoil along an aridity gradientSoil total phosphorus and nitrogen explain vegetation community composition in a northern forest ecosystem near a phosphate massifContrasting conifer species productivity in relation to soil carbon, nitrogen and phosphorus stoichiometry of British Columbia perhumid rainforestsIncreasing soil carbon stocks in eight permanent forest plots in ChinaEstimates of mean residence times of phosphorus in commonly considered inorganic soil phosphorus poolsLability classification of soil organic matter in the northern permafrost regionCurrent, steady-state and historical weathering rates of base cations at two forest sites in northern and southern Sweden: a comparison of three methodsAnoxic conditions maintained high phosphorus sorption in humid tropical forest soilsReviews and syntheses: Agropedogenesis – humankind as the sixth soil-forming factor and attractors of agricultural soil degradationWeathering rates in Swedish forest soilsExogenous phosphorus compounds interact with nitrogen availability to regulate dynamics of soil inorganic phosphorus fractions in a meadow steppeThe simulated N 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processes in the soil phosphorus cycleFrequency and intensity of nitrogen addition alter soil inorganic sulfur fractions, but the effects vary with mowing management in a temperate steppeGlobal soil–climate–biome diagram: linking surface soil properties to climate and biota
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.
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.
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.
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.
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.
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.
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.
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.
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.
Severin-Luca Bellè, Asmeret Asefaw Berhe, Frank Hagedorn, Cristina Santin, Marcus Schiedung, Ilja van Meerveld, and Samuel Abiven
Revised manuscript accepted for BGShort 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.
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.
Mathieu Chassé, Suzanne Luftalla, Lauric Cécillon, François Baudin, Samuel Abiven, Claire Chenu, and Pierre Barré
Revised manuscript accepted for BGShort summary
Evolution of organic carbon content in soils could be a major driver of atmospheric greenhouse gas concentrations over the next century. Understanding the 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 characterisation of carbon pools with distinct residence time in soils and gives insight on the mechanisms explaining soil organic carbon persistence.
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.
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.
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
Revised manuscript accepted for BGShort 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.
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.
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.
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
Revised manuscript accepted for BGShort 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.
Lena Rohe, Bernd Apelt, Hans-Jörg Vogel, Reinhard Well, Gi-Mick Wu, and Steffen Schlüter
Revised manuscript accepted for BGShort summary
This study presents a well-defined and comprehensive experimental setup analyzing total denitrification, i.e. N2O and (N2O+N2) fluxes, in combination with X-ray CT image analysis. (N2O+N2) fluxes were mainly controlled by the interplay of oxygen supply and demand. The former could be estimated by abiotic proxies like the extent of anaerobic soil volumes or diffusivity, whereas the latter was best described by CO2 production or SOM. N2O fluxes additionally depended on the N2O reduction.
Marion Schrumpf, Klaus Kaiser, Allegra Mayer, Günter Hempel, and Susan Trumbore
Revised manuscript accepted for BGShort summary
Large amounts of organic carbon (OC) in soil are 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.
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.
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.
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.
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.
Marijn Van de Broek, Shiva Ghiasi, Charlotte Decock, Andreas Hund, Samuel Abiven, Cordula Friedli, Roland A. Werner, and Johan Six
Biogeosciences, 17, 2971–2986,Short summary
Four wheat cultivars were labeled with 13CO2 to quantify the effect of rooting depth and root biomass on the belowground transfer of organic carbon. We found no clear relation between the time since cultivar development and the amount of carbon inputs to the soil. Therefore, the hypothesis that wheat cultivars with a larger root biomass and deeper roots promote carbon stabilization was rejected. The amount of root biomass that will be stabilized in the soil on the long term is, however, unknown.
Michael Rinderer, Jaane Krüger, Friederike Lang, Heike Puhlmann, and Markus Weiler
Revised manuscript accepted for BGShort summary
To quantify Phosphorus loss from forests by vertical and lateral soil water flow, we conducted six sprinkling experiments at three beech forests in Germany. Out data showed a nutrient flashing (high P concentrations) during the first 2 hours after the onset but no further depletion thereafter. This suggest that the mobilization of P can keep up with its transport. We also showed that the P concentrations decreased with soil depth suggesting an efficient retention of P in the forest soil.
Carolyn J. Ewers Lewis, Mary A. Young, Daniel Ierodiaconou, Jeffrey A. Baldock, Bruce Hawke, Jonathan Sanderman, Paul E. Carnell, and Peter I. Macreadie
Biogeosciences, 17, 2041–2059,Short summary
Blue carbonecosystems – tidal marsh, mangrove, and seagrass – serve as important organic carbon sinks, mitigating impacts of climate change. We utilized a robust regional carbon stock dataset to identify ecological, geomorphological, and anthropogenic drivers of carbon stock variability and create high-spatial-resolution predictive carbon stock maps. This work facilitates strategic conservation and restoration of coastal blue carbon ecosystems to contribute to climate change mitigation.
Yuqing Liu, Wenhong Ma, Dan Kou, Xiaxia Niu, Tian Wang, Yongliang Chen, Dima Chen, Xiaoqin Zhu, Mengying Zhao, Baihui Hao, Jinbo Zhang, Yuanhe Yang, and Huifeng Hu
Biogeosciences, 17, 2009–2019,Short summary
The microbial C : N ratio increased with aridity, while the microbial N : P ratio decreased with aridity, which implied that drought-stimulated microbes tend to be more N conservative. Among all examined ecological factors, substrate supply and microbial structure together controlled the microbial stoichiometry. Overall, these results illustrated N and P limitation in microbial biomass at deeper soil depths along the aridity gradient and limited responses to ecological factors in the subsoil.
Laura Matkala, Maija Salemaa, and Jaana Bäck
Biogeosciences, 17, 1535–1556,Short summary
We studied how species number and abundance of the understorey vegetation correlates with nutrient contents of soil and tree leaves at a northern boreal forest site. The phosphorus (P) content of the humus layer showed higher correlation with vegetation than the nitrogen (N) content. Usually N is considered more important in boreal forests. The plots with high P content in humus had birch as the dominant tree species, implying that birch leaf litter is an important source of P to the plants.
John Marty Kranabetter, Ariana Sholinder, and Louise de Montigny
Biogeosciences, 17, 1247–1260,Short summary
Temperate rainforests of the Pacific Northwest often have productive soils with high levels of organic matter. We describe the nitrogen and phosphorus attributes of this soil organic matter in relation to the growth of four conifer species. Sitka spruce thrived on high-nitrogen soils, more so than the other conifer species, but productivity overall is likely constrained by phosphorus deficiencies. Study results will guide wood production, carbon sequestration and conservation priorities.
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.
Julian Helfenstein, Chiara Pistocchi, Astrid Oberson, Federica Tamburini, Daniel S. Goll, and Emmanuel Frossard
Biogeosciences, 17, 441–454,Short summary
In this article we provide estimates of mean residence times of phosphorus in inorganic soil phosphorus pools. These values improve our understanding of the dynamics of phosphorus cycling and can be used to improve global land surface models.
Peter Kuhry, Jiří Bárta, Daan Blok, Bo Elberling, Samuel Faucherre, Gustaf Hugelius, Christian J. Jørgensen, Andreas Richter, Hana Šantrůčková, and Niels Weiss
Biogeosciences, 17, 361–379,
Sophie Casetou-Gustafson, Harald Grip, Stephen Hillier, Sune Linder, Bengt A. Olsson, Magnus Simonsson, and Johan Stendahl
Biogeosciences, 17, 281–304,Short summary
Reliable methods are required for estimating mineral supply rates to forest growth from weathering. We applied the depletion method, the PROFILE model and the base cation budget method to two forest sites in Sweden. The highest weathering rate was obtained from the budget method and the lowest from the depletion method. The high rate by the budget method suggests that there were additional sources for tree uptake not captured by measurements.
Yang Lin, Avner Gross, Christine S. O'Connell, and Whendee L. Silver
Biogeosciences, 17, 89–101,Short summary
Phosphorus (P) is an important soil nutrient that often limits plant growth and microbial activity in humid tropical forests. These ecosystems receive a large amount of rainfall that helps create frequent anoxic events in soils. Our results show that anoxic conditions reduced the strength of soil minerals to bind P even though a large amount of P was still bound to minerals. Our study suggests that anoxic events might serve as hot moments for plants and microbes to acquire P.
Yakov Kuzyakov and Kazem Zamanian
Biogeosciences, 16, 4783–4803,Short summary
Agropedogenesis, i.e. soil development under agricultural use, is the anthropogenic modification of soil and environmental factors for optimization of crop production. Maximization of only this function, crop production, leads to declines in all other soil functions and consequently promotes uniformity in soil properties around the globe. Here we developed a new scientific background for the theory of agropedogenesis and the identification of soil degradation stages.
Cecilia Akselsson, Salim Belyazid, Johan Stendahl, Roger Finlay, Bengt A. Olsson, Martin Erlandsson Lampa, Håkan Wallander, Jon Petter Gustafsson, and Kevin Bishop
Biogeosciences, 16, 4429–4450,Short summary
The release of elements from soil through weathering is an important process, controlling nutrient availability for plants and recovery from acidification. However, direct measurements cannot be done, and present estimates are burdened with high uncertainties. In this paper we use different approaches to quantify weathering rates in different scales in Sweden and discuss the pros and cons. The study contributes to more robust assessments of sustainable harvesting of forest biomass.
Heyong Liu, Ruzhen Wang, Hongyi Wang, Yanzhuo Cao, Feike A. Dijkstra, Zhan Shi, Jiangping Cai, Zhengwen Wang, Hongtao Zou, and Yong Jiang
Biogeosciences, 16, 4293–4306,
Yanxia Nie, Xiaoge Han, Jie Chen, Mengcen Wang, and Weijun Shen
Biogeosciences, 16, 4277–4291,Short summary
The N–transformation rates and N–related functional gene abundance were surveyed in a tropical forest soil with experimental N additions. The C : N ratio was the determinant factor for N transformations in the dry season while the microbial biomass was the one in the wet season. This study also found that high N addition imposed significant positive effects on the functional gene abundance of AOA amoA and nirK but negative effects on that of AOB amoA and nosZ.
Axel Don, Christina Hagen, Erik Grüneberg, and Cora Vos
Biogeosciences, 16, 4145–4155,Short summary
Forest soils have a steep carbon gradient from the forest floor to the mineral soil, indicating that carbon is prevented from entry into the soil. Wild boar are effective in mixing the soil when searching for food. In a 6–year field study, we found no significant changes in soil organic carbon stocks in the wild boar treatment plots. However, around 50 % of forest floor carbon was transferred with mixing into mineral soil carbon and increased the stabilised fraction of soil organic carbon.
Sarah W. Keenan, Sean M. Schaeffer, and Jennifer M. DeBruyn
Biogeosciences, 16, 3929–3939,Short summary
Decaying animals perturb soil biogeochemical cycles. Stable δ15N composition, which reflects the sum of all biogeochemical processes, increases during decay and persists for years. Enrichment following beaver decay persisted after at least 1 year, and was evident up to 10 cm depth and 60 cm from the decaying animals, beyond where soils were visibly impacted by decomposition. Nutrients sourced from decaying animals represent an integral and long–lived component of nitrogen cycling in soils.
Aditi Sengupta, Julia Indivero, Cailene Gunn, Malak M. Tfaily, Rosalie K. Chu, Jason Toyoda, Vanessa L. Bailey, Nicholas D. Ward, and James C. Stegen
Biogeosciences, 16, 3911–3928,Short summary
Coastal terrestrial–aquatic interfaces represent dynamic yet poorly understood zones of biogeochemical cycles. We evaluated associations between the soil salinity gradient, molecular-level soil-C chemistry, and microbial community assembly processes in a coastal watershed on the Olympic Peninsula in Washington, USA. Results revealed salinity-driven gradients in molecular-level C chemistry, with little evidence of an association between C chemistry and microbial community assembly processes.
Steffen Schlüter, Jan Zawallich, Hans-Jörg Vogel, and Peter Dörsch
Biogeosciences, 16, 3665–3678,Short summary
A combination of gas chromatography and X-ray CT reveals the microscale processes that govern soil respiration. Aerobic and anaerobic respiration in microbial hotspots depends not only on the quality and quantity of soil organic matter, but also on the spatial distribution of hotspots. Denitrification kinetics are mainly governed by hotspot architecture due to local competition for oxygen during growth. Cumulative behavior is mainly governed by water saturation due to the overall supply with O2.
Nicholas P. Rosenstock, Patrick A. W. van Hees, Petra M. A. Fransson, Roger D. Finlay, and Anna Rosling
Biogeosciences, 16, 3637–3649,Short summary
We examined the effects of elevated CO2, pine seedlings, and ectomycorrhizal fungi on mineral weathering. Seedlings significantly increased mineral weathering, while elevated CO2 increased plant growth and organic acid concentrations but had no effect on weathering. Ectomycorrhial fungi showed some tendency to increase weathering. We conclude that nutrient uptake, which reduces transport limitation to weathering, is the primary mechanism by which plants enhanced weathering in this system.
Zhenjiao Cao, Yufu Jia, Yue Cai, Xin Wang, Huifeng Hu, Jinbo Zhang, Juan Jia, and Xiaojuan Feng
Biogeosciences, 16, 3605–3619,Short summary
Using pathway analysis, we demonstrate that past aridity's effect is mediated by differential mechanisms for substrates of varied complexity. While microbial biomass plays a more important role in the decomposition of fresh litter, enzyme-catalyzed extracellular reactions predominantly govern the mineralization of SOC. Our findings have significant implications for assessing and modeling decomposition in different aridity regimes.
Zhiwei Xu, Guirui Yu, Qiufeng Wang, Xinyu Zhang, Ruili Wang, Ning Zhao, Nianpeng He, and Ziping Liu
Biogeosciences, 16, 3333–3349,Short summary
Plant functional traits have increasingly been studied as determinants of ecosystem properties. While the relationships between biological community structures and ecological functions remain poorly understood at the large scale, we found that there was considerable variation in the profiles of different substrate uses along the NSTEC. The soil silt content and plant functional traits together shaped the biogeographical pattern of the soil microbial substrate use.
Tessa Sophia van der Voort, Utsav Mannu, Frank Hagedorn, Cameron McIntyre, Lorenz Walthert, Patrick Schleppi, Negar Haghipour, and Timothy Ian Eglinton
Biogeosciences, 16, 3233–3246,Short summary
The carbon stored in soils is the largest reservoir of organic carbon on land. In the context of greenhouse gas emissions and a changing climate, it is very important to understand how stable the carbon in the soil is and why. The deeper parts of the soil have often been overlooked even though they store a lot of carbon. In this paper, we discovered that although deep soil carbon is expected to be old and stable, there can be a significant young component that cycles much faster.
Wolfgang Wanek, David Zezula, Daniel Wasner, Maria Mooshammer, and Judith Prommer
Biogeosciences, 16, 3047–3068,Short summary
Efforts to understand the global phosphorus (P) cycle are limited by the scarcity of global data on rates of soil P processes, as well as on its environmental controls. Here, we present a novel approach using radiophosphorus labeling of soils, which allows for the measurement of fluxes of abiotic and biotic soil P processes. This approach is also suitable for strongly weathered and P-depleted soils. Biotic processes are corrected for abiotic processes by comparing live and sterile soils.
Tianpeng Li, Heyong Liu, Ruzhen Wang, Xiao-Tao Lü, Junjie Yang, Yunhai Zhang, Peng He, Zhirui Wang, Xingguo Han, and Yong Jiang
Biogeosciences, 16, 2891–2904,
Xia Zhao, Yuanhe Yang, Haihua Shen, Xiaoqing Geng, and Jingyun Fang
Biogeosciences, 16, 2857–2871,Short summary
Surface soils interact strongly with both climate and biota and provide fundamental ecosystem services. However, the quantitative linkages between soil, climate, and biota remain unclear at a global scale. By compiling a large global soil database, we mapped eight major soil properties based on machine learning algorithms and developed a global soil–climate–biome diagram. Our results suggest shifts in soil properties under global climate and land cover change.
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Our analyses showed that soil biogeochemistry could distinguish two forest ecosystems that coexist in Quebec: open lichen woodlands and closed-canopy black spruce–moss forests. Variations in carbon stocks, base cation concentrations and crystallinity of aluminium and iron were related to the different vegetation covers. This research was carried out as a first step to identify geochemical indicators of canopy cover types that could be useful in further palaeoecological studies.
Our analyses showed that soil biogeochemistry could distinguish two forest ecosystems that...