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1. Aggregate formation and carbon sequestration by earthworms in soil from a temperate forest exposed to elevated atmospheric CO2: A microcosm experiment

Author:
Sánchez-de León, Yaniria; Lugo-Pérez, Javier; Wise, David H.; Jastrow, Julie D.; González-Meler, Miquel A.
Source:
Soil biology & biochemistry 2014 v.68 pp. 223-230
ISSN:
0038-0717
Subject:
carbon dioxide; soil formation; Liquidambar styraciflua; nitrogen; plant residues; soil organic matter; soil stabilization; temperate forests; free air carbon dioxide enrichment; carbon; carbon sequestration; feeding behavior; earthworms; forest plantations; Lumbricus rubellus; stable isotopes; leaves; soil aggregates
Abstract:
... The role of soils in mitigating increases in atmospheric carbon dioxide (CO2) levels is uncertain, in part for the complex biotic and abiotic interactions determining soil carbon change. Earthworms, in particular, interact with the physical and chemical protection mechanisms of organic matter, major determinants of carbon storage capacity of soils. Studies of a Liquidambar styraciflua forest plant ...
DOI:
10.1016/j.soilbio.2013.09.023

2. Homoacetogenesis: A potentially underappreciated carbon pathway in peatlands

Author:
Ye, Rongzhong; Jin, Qusheng; Bohannan, Brendan; Keller, Jason K.; Bridgham, Scott D.
Source:
Soil biology & biochemistry 2014 v.68 pp. 385-391
ISSN:
0038-0717
Subject:
acetates; acetyl coenzyme A; anaerobic conditions; carbon; carbon cycle; carbon dioxide; fermentation; greenhouse gases; methane; methane production; methanogens; peatlands; soil; swamps; thermodynamics; tracer techniques
Abstract:
... Due to anaerobic conditions, peatland soils store globally significant amounts of carbon and are an important source of methane, a potent greenhouse gas. One component of anaerobic carbon cycling, homoacetogenesis (i.e., acetate formation from carbon dioxide and dihydrogen via the acetyl-CoA pathway), has rarely been quantified in natural environments because it is commonly viewed as being thermod ...
DOI:
10.1016/j.soilbio.2013.10.020

3. Loss of labile carbon following soil disturbance determined by measurement of respired ∂13CO2

Author:
Zakharova, A.; Midwood, A.J.; Hunt, J.E.; Graham, S.L.; Artz, R.R.E.; Turnbull, M.H.; Whitehead, D.; Millard, P.
Source:
Soil biology & biochemistry 2014 v.68 pp. 125-132
ISSN:
0038-0717
Subject:
allophane; carbon; carbon dioxide; carbon sinks; disturbed soils; soil sampling; terrestrial ecosystems
Abstract:
... Soils are the largest pool of carbon (C) in terrestrial ecosystems with labile C being particularly vulnerable to loss. In this study we incubated a range of soils in both the short- (minutes) and long-term (months) to assess the loss of labile soil C by measuring the isotopic signature of soil respired CO2 (∂13CO2). Strong temporal trends in ∂13CO2 values were observed following soil disturbance: ...
DOI:
10.1016/j.soilbio.2013.10.001

4. Nutrient and carbon dynamics in peat from rich fens and Sphagnum-fens during different gradations of drought

Author:
Mettrop, Ivan S.; Cusell, Casper; Kooijman, Annemieke M.; Lamers, Leon P.M.
Source:
Soil biology & biochemistry 2014 v.68 pp. 317-328
ISSN:
0038-0717
Subject:
aeration; biodegradation; carbon; denitrification; drought; fens; flooded conditions; microbial biomass; mineralization; mortality; oxygen; peat; peat soils; peatlands
Abstract:
... Drought has major impacts on microbial decomposition and net N- and P-release in peat. The separate effects of aeration (oxygen intrusion) during moderate drought and desiccation (oxygen intrusion plus water deficiency) during severe drought are, however, poorly understood. This information is vital to understand the biogeochemical and ecological effects of different gradations of drought in peatl ...
DOI:
10.1016/j.soilbio.2013.10.023

5. Nutrient availability limits carbon sequestration in arable soils

Author:
Kirkby, Clive A.; Richardson, Alan E.; Wade, Len J.; Passioura, John B.; Batten, Graeme D.; Blanchard, Chris; Kirkegaard, John A.
Source:
Soil biology & biochemistry 2014 v.68 pp. 402-409
ISSN:
0038-0717
Subject:
agricultural soils; agroecosystems; arable soils; carbon; carbon sequestration; clay fraction; climate change; crop production; hydrogen; nitrogen; nutrient availability; nutrients; oxygen; phosphorus; soil organic matter; straw; sulfur
Abstract:
... Soils are the largest reservoir of global terrestrial carbon (C). Conversion from natural to agricultural ecosystems has generally resulted in a significant loss of soil organic-C (SOC, up to 50% or ∼30–40 t ha−1) and ‘restoring’ this lost C is a significant global challenge. The most stable component of soil organic matter (SOM), hereafter referred to as fine fraction SOM (FF-SOM), contains not o ...
DOI:
10.1016/j.soilbio.2013.09.032

6. Short-term utilization of carbon by the soil microbial community under future climatic conditions in a temperate heathland

Author:
Reinsch, Sabine; Michelsen, Anders; Sárossy, Zsuzsa; Egsgaard, Helge; Schmidt, Inger Kappel; Jakobsen, Iver; Ambus, Per
Source:
Soil biology & biochemistry 2014 v.68 pp. 9-19
ISSN:
0038-0717
Subject:
Actinobacteria; Gram-negative bacteria; Gram-positive bacteria; bacterial communities; biomarkers; carbon; carbon dioxide; carbon dioxide enrichment; climatic factors; drought; fungi; grasslands; heathlands; microbial biomass; phospholipid fatty acids; rhizosphere; roots; soil; soil microorganisms; summer; temperature
Abstract:
... An in-situ13C pulse-labeling experiment was carried out in a temperate heath/grassland to study the impacts of elevated CO2 concentration (510 ppm), prolonged summer droughts (annual exclusion of 7.6 ± 0.8%) and increased temperature (∼1 °C) on belowground carbon (C) utilization. Recently assimilated C (13C from the pulse-label) was traced into roots, soil and microbial biomass 1, 2 and 8 days aft ...
DOI:
10.1016/j.soilbio.2013.09.014

7. Soil aggregate size distribution mediates microbial climate change feedbacks

Author:
Nie, Ming; Pendall, Elise; Bell, Colin; Wallenstein, Matthew D.
Source:
Soil biology & biochemistry 2014 v.68 pp. 357-365
ISSN:
0038-0717
Subject:
carbon; carbon dioxide; carbon dioxide enrichment; carbon sequestration; climate; climate change; enzyme activity; enzymes; microaggregates; microbial activity; microbial biomass; models; soil microorganisms; soil organic matter; stoichiometry
Abstract:
... Soil carbon stabilization is known to depend in part on its distribution in structural aggregates, and upon soil microbial activity within the aggregates. However, the influence of climate change on continued soil C storage within aggregates of different size classes is unknown. In this study, we applied a modified dry-sieving technique to separate bulk soil into three fractions (>1 mm large macro ...
DOI:
10.1016/j.soilbio.2013.10.012
CHORUS:
10.1016/j.soilbio.2013.10.012

8. Soil enzyme activities, microbial communities, and carbon and nitrogen availability in organic agroecosystems across an intensively-managed agricultural landscape

Author:
Bowles, Timothy M.; Acosta-Martínez, Veronica; Calderón, Francisco; Jackson, Louise E.
Source:
Soil biology & biochemistry 2014 v.68 pp. 252
ISSN:
0038-0717
Subject:
Solanum lycopersicum var. lycopersicum; agricultural land; agroecosystems; biogeochemical cycles; carbon; community structure; environmental factors; enzyme activity; enzymes; fatty acid methyl esters; fungi; green waste; growing season; landscapes; microbial communities; nitrogen; nutrient management; organic production; phosphorus; saprophytes; soil enzymes; soil microorganisms; soil nutrients; soil pH; soil texture; sulfur; tomatoes; Central Valley of California
Abstract:
... Variability in the activity and composition of soil microbial communities may have important implications for the suite of microbially-derived ecosystem functions upon which agricultural systems rely, particularly organic agriculture. An on-farm approach was used to investigate microbial communities and soil carbon (C) and nitrogen (N) availability on 13 organically-managed fields growing Roma-typ ...
Handle:
10113/61980
DOI:
10.1016/j.soilbio.2013.10.004

9. A co-pyrolysis route to synthesize nitrogen doped multiwall carbon nanotubes for oxygen reduction reaction

Author:
Wang, Yongxia; Cui, Xiangzhi; Li, Yongsheng; Chen, Lisong; Chen, Hangrong; Zhang, Lingxia; Shi, Jianlin
Source:
Carbon 2014 v.68 pp. 232-239
ISSN:
0008-6223
Subject:
carbon; carbon nanotubes; catalysts; catalytic activity; chemical reduction; electrochemistry; fuel cells; iron; nitrogen; porous media; pyrolysis; silica
Abstract:
... Nitrogen-doped multiwall carbon nanotubes (N-MWCNTs) have been synthesized by a co-pyrolysis route of iron(II) phthalocyanine (FePc) loaded and PEO20–PPO70–PEO20 retained in mesoporous silica. In this process, FePc was used as both Fe-catalyst, carbon and nitrogen sources, and P123-containing mesoporous silica was employed as both the substrate and carbon seeds/source for the growth of N-MWCNTs. T ...
DOI:
10.1016/j.carbon.2013.10.083

10. Actuation triggered exfoliation of graphene oxide at low temperature for electrochemical capacitor applications

Author:
Sun, Gengzhi; Zheng, Lianxi; Zhan, Zhaoyao; Zhou, Jinyuan; Liu, Xianbin; Li, Lin
Source:
Carbon 2014 v.68 pp. 748-754
ISSN:
0008-6223
Subject:
X-ray photoelectron spectroscopy; atmospheric pressure; capacitance; carbon; electrical equipment; electrochemistry; graphene oxide; paper; scanning electron microscopy; temperature
Abstract:
... An actuation triggered thermal exfoliation process was realized at a low temperature of 200°C and atmospheric pressure. Densely packed graphene oxide (GO) paper was transformed into airy-like expanded architectures. The underlying mechanism was found to be similar to corn popping and attributed to the thermally-stimulated-actuation and molecules escape. Scanning electron microscopy, X-ray photoele ...
DOI:
10.1016/j.carbon.2013.11.063

11. Bio-renewable precursor fibers from lignin/polylactide blends for conversion to carbon fibers

Author:
Thunga, Mahendra; Chen, Keke; Grewell, David; Kessler, Michael R.
Source:
Carbon 2014 v.68 pp. 159-166
ISSN:
0008-6223
Subject:
biopolymers; carbon; carbon fibers; coproducts; differential scanning calorimetry; lignin; mechanical properties; melting; microstructure; mixing; moieties; polylactic acid; porous media; scanning electron microscopy; spinning; thermal stability; thermogravimetry; transmission electron microscopy
Abstract:
... Lignin, a highly aromatic biopolymer extracted as a coproduct of wood pulping, was investigated as a suitable precursor for carbon fibers. Lignin was chemically modified and blended with poly(lactic acid) (PLA) biopolymer before melt spinning into lignin fibers. The chemical modification of raw lignin involved butyration to form ester functional groups in place of polar hydroxyl (–OH) groups, whic ...
DOI:
10.1016/j.carbon.2013.10.075

12. Broadband electromagnetic characterization of carbon foam to metal contact

Author:
Micheli, D.; Morles, R.B.; Marchetti, M.; Moglie, F.; Mariani Primiani, V.
Source:
Carbon 2014 v.68 pp. 149-158
ISSN:
0008-6223
Subject:
carbon; finite element analysis; foams; mathematical models; microstructure; scanning electron microscopes
Abstract:
... We investigated how the electrical contact of carbon foam with metallic surface can reduce its shielding properties. The bubble structure of the foam does not ensure a good electrical contact with the metal, and it leads to a significant reduction of the shielding effectiveness. A finite element numerical simulation was carried out by adopting a bubble/pore model of the internal microstructure of ...
DOI:
10.1016/j.carbon.2013.10.074

13. Characterization of flame-generated 2-D carbon nano-disks

Author:
Minutolo, Patrizia; Commodo, Mario; Santamaria, Alexander; De Falco, Gianluigi; D’Anna, Andrea
Source:
Carbon 2014 v.68 pp. 138-148
ISSN:
0008-6223
Subject:
Raman spectroscopy; aromatic compounds; atomic force microscopy; carbon; chemical composition; nanomaterials; sampling
Abstract:
... Two-dimensional carbon nanostructures have been produced via flame synthesis. Flame conditions and sampling methods have been optimized for the collection of the carbon nanostructures and for their characterization. Atomic Force Microscopy, Differential Mobility Analysis and Raman spectroscopy have been used to characterize the morphology and the chemical composition of these carbon nanostructures ...
DOI:
10.1016/j.carbon.2013.10.073

14. Chemical mechanical polishing of thin film diamond

Author:
Thomas, Evan L.H.; Nelson, Geoffrey W.; Mandal, Soumen; Foord, John S.; Williams, Oliver A.
Source:
Carbon 2014 v.68 pp. 473-479
ISSN:
0008-6223
Subject:
X-ray photoelectron spectroscopy; atomic force microscopy; carbon; modulus of elasticity; nanocrystals; oxidation; polyesters; polyurethanes; roughness; scanning electron microscopy; silica; temperature
Abstract:
... The demonstration that Nanocrystalline Diamond (NCD) can retain the superior Young’s modulus (1100GPa) of single crystal diamond twinned with its ability to be grown at low temperatures (<450°C) has driven a revival into the growth and applications of NCD thin films. However, owing to the competitive growth of crystals the resulting film has a roughness that evolves with film thickness, preventing ...
DOI:
10.1016/j.carbon.2013.11.023

15. Controllable synthesis of single- and double-walled carbon nanotubes from petroleum coke and their application to solar cells

Author:
Xu, Kai; Li, Yongfeng; Yang, Fan; Yang, Wang; Zhang, Liqiang; Xu, Chunming; Kaneko, Toshiro; Hatakeyama, Rikizo
Source:
Carbon 2014 v.68 pp. 511-519
ISSN:
0008-6223
Subject:
Raman spectroscopy; X-ray photoelectron spectroscopy; argon (noble gases); carbon; carbon nanotubes; catalysts; diodes; energy-dispersive X-ray analysis; infrared spectroscopy; iron; lighting; petroleum; scanning electron microscopy; silicon; solar cells; spectrometers; thermogravimetry; transmission electron microscopy; ultraviolet-visible spectroscopy; wavelengths
Abstract:
... Single- and double-walled carbon nanotubes (SWCNTs and DWCNTs) have been controllably synthesized by an arc discharge in different atmosphere using petroleum coke as carbon source. The morphology and properties of two kinds of carbon nanotubes (CNTs) synthesized with Fe as catalyst were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, Raman spectrosc ...
DOI:
10.1016/j.carbon.2013.11.028

16. Dense carbon monoliths for supercapacitors with outstanding volumetric capacitances

Author:
Kunowsky, M.; Garcia-Gomez, A.; Barranco, V.; Rojo, J.M.; Ibañez, J.; Carruthers, J.D.; Linares-Solano, A.
Source:
Carbon 2014 v.68 pp. 553-562
ISSN:
0008-6223
Subject:
capacitance; carbon; electrical conductivity; electrical equipment; electrochemistry; electrodes; oxygen; porosity; porous media; surface area
Abstract:
... A commercially available dense carbon monolith (CM) and four carbon monoliths obtained from it have been studied as electrochemical capacitor electrodes in a two-electrode cell. CM has: (i) very high density (1.17gcm⁻³), (ii) high electrical conductivity (9.3Scm⁻¹), (iii) well-compacted and interconnected carbon spheres, (iv) homogeneous microporous structure and (v) apparent BET surface area of 9 ...
DOI:
10.1016/j.carbon.2013.11.034

17. Density control of carbon nanowalls grown by CH4/H2 plasma and their electrical properties

Author:
Cho, Hyung Jun; Kondo, Hiroki; Ishikawa, Kenji; Sekine, Makoto; Hiramatsu, Mineo; Hori, Masaru
Source:
Carbon 2014 v.68 pp. 380-388
ISSN:
0008-6223
Subject:
carbon; chemical bonding; electrical conductivity; hydrogen; methane; spectroscopy; vapors
Abstract:
... We report on successful control of the density of carbon nanowalls (CNWs) synthesized using radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) employing CH4/H2 plasma, by varying the total pressure and discharge power during growth. As the total pressure was decreased or the power was increased, the density of CNWs decreased in conjunction with an increase in the H atom density ...
DOI:
10.1016/j.carbon.2013.11.014

18. Disordered mesoporous carbon as polysulfide reservoir for improved cyclic performance of lithium–sulfur batteries

Author:
Park, Min-Sik; Jeong, Bo Ock; Kim, Tae Jeong; Kim, Seok; Kim, Ki Jae; Yu, Ji-Sang; Jung, Yongju; Kim, Young-Jun
Source:
Carbon 2014 v.68 pp. 265-272
ISSN:
0008-6223
Subject:
absorption; batteries; carbon; cathodes; electrochemistry; porosity; porous media; silica; sulfur
Abstract:
... Mesoporous carbon, which was templated by colloidal silica, was added to a sulfur cathode as a functional material to confine polysulfides to improve the cyclic performance of lithium–sulfur batteries. To investigate the effect of the pore size and the pore volume of mesoporous carbon on the absorption characteristics of the Li-polysulfides, mesoporous carbons with various pore sizes and total por ...
DOI:
10.1016/j.carbon.2013.11.001

19. Dispersion of single-walled carbon nanotubes by intense turbulent shear in micro-channels

Author:
Luo, Peicheng; Wu, Hua; Morbidelli, Massimo
Source:
Carbon 2014 v.68 pp. 610-618
ISSN:
0008-6223
Subject:
aqueous solutions; carbon; carbon nanotubes; dispersions; internal transcribed spacers; light scattering; sodium dodecylbenzenesulfonate; solvents; sonication
Abstract:
... Dispersion of carbon nanotubes (CNTs) in solvents is a prerequisite for arriving at their expected performances in applications. Our objective is twofold. We first assess an intense turbulent shear (ITS) method in a micro-channel system, with a shear rate of 3×10⁶s⁻¹, in preparing single-walled CNT (SWCNT) dispersions in aqueous solution of sodium dodecyl benzene sulfonate, and compare it with son ...
DOI:
10.1016/j.carbon.2013.11.040

20. Dissolved black nitrogen (DBN) in freshwater environments

Author:
Ding, Yan; Watanabe, Akira; Jaffé, Rudolf
Source:
Organic geochemistry 2014 v.68 pp. 1-4
ISSN:
0146-6380
Subject:
aquatic environment; biomass; burning; carbon; carbon cycle; combustion; community structure; dissolved organic matter; freshwater; heterocyclic compounds; microbial communities; nitrogen; soil; streams; ultrafiltration; North America
Abstract:
... Biomass burning results in the formation and accumulation of pyrogenic products such as black carbon (BC) and black nitrogen (BN) in soils. The ubiquitous presence of pyrogenic products in natural dissolved organic matter (DOM) and potential implications in global carbon cycling have recently been reported. However, little is known about the environmental dynamics or the importance in the global N ...
DOI:
10.1016/j.orggeochem.2013.12.009