Base de dados : MEDLINE
Pesquisa : G02.607.125 [Categoria DeCS]
Referências encontradas : 1437 [refinar]
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  1 / 1437 MEDLINE  
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[PMID]:29335469
[Au] Autor:Aunkham A; Zahn M; Kesireddy A; Pothula KR; Schulte A; Baslé A; Kleinekathöfer U; Suginta W; van den Berg B
[Ad] Endereço:Biochemistry-Electrochemistry Research Unit, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
[Ti] Título:Structural basis for chitin acquisition by marine Vibrio species.
[So] Source:Nat Commun;9(1):220, 2018 01 15.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chitin, an insoluble polymer of N-acetylglucosamine, is one of the most abundant biopolymers on Earth. By degrading chitin, chitinolytic bacteria such as Vibrio harveyi are critical for chitin recycling and maintenance of carbon and nitrogen cycles in the world's oceans. A decisive step in chitin degradation is the uptake of chito-oligosaccharides by an outer membrane protein channel named chitoporin (ChiP). Here, we report X-ray crystal structures of ChiP from V. harveyi in the presence and absence of chito-oligosaccharides. Structures without bound sugar reveal a trimeric assembly with an unprecedented closing of the transport pore by the N-terminus of a neighboring subunit. Substrate binding ejects the pore plug to open the transport channel. Together with molecular dynamics simulations, electrophysiology and in vitro transport assays our data provide an explanation for the exceptional affinity of ChiP for chito-oligosaccharides and point to an important role of the N-terminal gate in substrate transport.
[Mh] Termos MeSH primário: Carbono/metabolismo
Quitina/metabolismo
Nitrogênio/metabolismo
Vibrio/metabolismo
[Mh] Termos MeSH secundário: Acetilglucosamina/metabolismo
Proteínas da Membrana Bacteriana Externa/química
Proteínas da Membrana Bacteriana Externa/genética
Proteínas da Membrana Bacteriana Externa/metabolismo
Ciclo do Carbono
Cristalografia por Raios X
Modelos Moleculares
Ciclo do Nitrogênio
Oceanos e Mares
Oligossacarídeos/metabolismo
Porinas/química
Porinas/genética
Porinas/metabolismo
Conformação Proteica
Água do Mar/química
Água do Mar/microbiologia
Vibrio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Oligosaccharides); 0 (Porins); 1398-61-4 (Chitin); 7440-44-0 (Carbon); N762921K75 (Nitrogen); V956696549 (Acetylglucosamine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02523-y


  2 / 1437 MEDLINE  
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[PMID]:29343713
[Au] Autor:Hare VJ; Loftus E; Jeffrey A; Ramsey CB
[Ad] Endereço:Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, 1 South Parks Road, Oxford, OX1 3TG, UK. vincent.john.hare@gmail.com.
[Ti] Título:Atmospheric CO effect on stable carbon isotope composition of terrestrial fossil archives.
[So] Source:Nat Commun;9(1):252, 2018 01 17.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The C/ C ratio of C plant matter is thought to be controlled by the isotopic composition of atmospheric CO and stomatal response to environmental conditions, particularly mean annual precipitation (MAP). The effect of CO concentration on C/ C ratios is currently debated, yet crucial to reconstructing ancient environments and quantifying the carbon cycle. Here we compare high-resolution ice core measurements of atmospheric CO with fossil plant and faunal isotope records. We show the effect of pCO during the last deglaciation is stronger for gymnosperms (-1.4 ± 1.2‰) than angiosperms/fauna (-0.5 ± 1.5‰), while the contributions from changing MAP are -0.3 ± 0.6‰ and -0.4 ± 0.4‰, respectively. Previous studies have assumed that plant C/ C ratios are mostly determined by MAP, an assumption which is sometimes incorrect in geological time. Atmospheric effects must be taken into account when interpreting terrestrial stable carbon isotopes, with important implications for past environments and climates, and understanding plant responses to climate change.
[Mh] Termos MeSH primário: Atmosfera/química
Dióxido de Carbono/química
Isótopos de Carbono/análise
Clima
Fósseis
Plantas/metabolismo
[Mh] Termos MeSH secundário: Ciclo do Carbono
Isótopos de Carbono/química
Mudança Climática
Fotossíntese
Chuvas
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Carbon Isotopes); 142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180119
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02691-x


  3 / 1437 MEDLINE  
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[PMID]:28470848
[Au] Autor:Camprubi E; Jordan SF; Vasiliadou R; Lane N
[Ad] Endereço:Department of Genetics, Evolution and Environment, University College London, London, UK.
[Ti] Título:Iron catalysis at the origin of life.
[So] Source:IUBMB Life;69(6):373-381, 2017 06.
[Is] ISSN:1521-6551
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Iron-sulphur proteins are ancient and drive fundamental processes in cells, notably electron transfer and CO fixation. Iron-sulphur minerals with equivalent structures could have played a key role in the origin of life. However, the 'iron-sulphur world' hypothesis has had a mixed reception, with questions raised especially about the feasibility of a pyrites-pulled reverse Krebs cycle. Phylogenetics suggests that the earliest cells drove carbon and energy metabolism via the acetyl CoA pathway, which is also replete in Fe(Ni)S proteins. Deep differences between bacteria and archaea in this pathway obscure the ancestral state. These differences make sense if early cells depended on natural proton gradients in alkaline hydrothermal vents. If so, the acetyl CoA pathway diverged with the origins of active ion pumping, and ancestral CO fixation might have been equivalent to methanogens, which depend on a membrane-bound NiFe hydrogenase, energy converting hydrogenase. This uses the proton-motive force to reduce ferredoxin, thence CO . The mechanism suggests that pH could modulate reduction potential at the active site of the enzyme, facilitating the difficult reduction of CO by H . This mechanism could be generalised under abiotic conditions so that steep pH differences across semi-conducting Fe(Ni)S barriers drives not just the first steps of CO fixation to C1 and C2 organics such as CO, CH SH and CH COSH, but a series of similar carbonylation and hydrogenation reactions to form longer chain carboxylic acids such as pyruvate, oxaloacetate and α-ketoglutarate, as in the incomplete reverse Krebs cycle found in methanogens. We suggest that the closure of a complete reverse Krebs cycle, by regenerating acetyl CoA directly, displaced the acetyl CoA pathway from many modern groups. A later reliance on acetyl CoA and ATP eliminated the need for the proton-motive force to drive most steps of the reverse Krebs cycle. © 2017 IUBMB Life, 69(6):373-381, 2017.
[Mh] Termos MeSH primário: Acetilcoenzima A/química
Ferredoxinas/química
Proteínas com Ferro-Enxofre/química
Ferro/química
Origem da Vida
[Mh] Termos MeSH secundário: Acetilcoenzima A/metabolismo
Archaea/química
Archaea/metabolismo
Bactérias/química
Bactérias/metabolismo
Ciclo do Carbono
Dióxido de Carbono/química
Dióxido de Carbono/metabolismo
Catálise
Ciclo do Ácido Cítrico
Ferredoxinas/metabolismo
Concentração de Íons de Hidrogênio
Fontes Hidrotermais
Ferro/metabolismo
Proteínas com Ferro-Enxofre/metabolismo
Ácidos Cetoglutáricos/química
Ácidos Cetoglutáricos/metabolismo
Ácido Oxaloacético/química
Ácido Oxaloacético/metabolismo
Prótons
Ácido Pirúvico/química
Ácido Pirúvico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferredoxins); 0 (Iron-Sulfur Proteins); 0 (Ketoglutaric Acids); 0 (Protons); 142M471B3J (Carbon Dioxide); 2F399MM81J (Oxaloacetic Acid); 72-89-9 (Acetyl Coenzyme A); 8558G7RUTR (Pyruvic Acid); 8ID597Z82X (alpha-ketoglutaric acid); E1UOL152H7 (Iron)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1002/iub.1632


  4 / 1437 MEDLINE  
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[PMID]:29472454
[Au] Autor:Hicks Pries CE; Castanha C; Porras R; Phillips C; Torn MS
[Ad] Endereço:Climate Sciences Department, Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, MS 74R316C, Berkeley, CA 94720, USA. caitlin.e.h.pries@dartmouth.edu mstorn@lbl.gov.
[Ti] Título:Response to Comment on "The whole-soil carbon flux in response to warming".
[So] Source:Science;359(6378), 2018 02 23.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Temperature records and model predictions demonstrate that deep soils warm at the same rate as surface soils, contrary to Xiao 's assertions. In response to Xiao 's critique of our Q analysis, we present the results with all data points included, which show Q values of >2 throughout the soil profile, indicating that all soil depths responded to warming.
[Mh] Termos MeSH primário: Ciclo do Carbono
Solo
[Mh] Termos MeSH secundário: Carbono
Microbiologia do Solo
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; COMMENT
[Nm] Nome de substância:
0 (Soil); 7440-44-0 (Carbon)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180224
[St] Status:MEDLINE


  5 / 1437 MEDLINE  
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[PMID]:29360853
[Au] Autor:Yuan X; Si Y; Lin W; Yang J; Wang Z; Zhang Q; Qian W; Chen Y; Yang Y
[Ad] Endereço:Key Laboratory for Subtropical Mountain Ecology, School of Geographical Science, Fujian Normal University, Fuzhou, China.
[Ti] Título:Effects of short-term warming and nitrogen addition on the quantity and quality of dissolved organic matter in a subtropical Cunninghamia lanceolata plantation.
[So] Source:PLoS One;13(1):e0191403, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Increasing temperature and nitrogen (N) deposition are two large-scale changes projected to occur over the coming decades. The effects of these changes on dissolved organic matter (DOM) are largely unknown. This study aimed to assess the effects of warming and N addition on the quantity and quality of DOM from a subtropical Cunninghamia lanceolata plantation. Between 2014 and 2016, soil solutions were collected from 0-15, 15-30, and 30-60 cm depths by using a negative pressure sampling method. The quantity and quality of DOM were measured under six different treatments. The spectra showed that the DOM of the forest soil solution mainly consisted of aromatic protein-like components, microbial degradation products, and negligible amounts of humic-like substances. Warming, N addition, and warming + N addition significantly inhibited the concentration of dissolved organic carbon (DOC) in the surface (0-15 cm) soil solution. Our results suggested that warming reduced the amount of DOM originating from microbes. The decrease in protein and carboxylic acid contents was mostly attributed to the reduction of DOC following N addition. The warming + N addition treatment showed an interactive effect rather than an additive effect. Thus, short-term warming and warming + N addition decreased the quantity of DOM and facilitated the migration of nutrients to deeper soils. Further, N addition increased the complexity of the DOM structure. Hence, the loss of soil nutrients and the rational application of N need to be considered in order to prevent the accumulation of N compounds in soil.
[Mh] Termos MeSH primário: Cunninghamia/metabolismo
Nitrogênio/metabolismo
[Mh] Termos MeSH secundário: Ciclo do Carbono
China
Cunninghamia/efeitos dos fármacos
Ecossistema
Aquecimento Global
Imagem Tridimensional
Modelos Biológicos
Nitrogênio/administração & dosagem
Nitrogênio/análise
Ciclo do Nitrogênio
Compostos Orgânicos/metabolismo
Solo/química
Solubilidade
Espectrometria de Fluorescência
Temperatura Ambiente
Clima Tropical
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Organic Chemicals); 0 (Soil); N762921K75 (Nitrogen)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180124
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191403


  6 / 1437 MEDLINE  
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[PMID]:29420277
[Au] Autor:Ragsdale SW
[Ad] Endereço:Department of Biological Chemistry, University of Michigan Medical School, 1150 West Medical Center Drive, Ann Arbor, MI 48109-0606, USA. sragsdal@umich.edu.
[Ti] Título:Stealth reactions driving carbon fixation.
[So] Source:Science;359(6375):517-518, 2018 02 02.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Fenômenos Fisiológicos Bacterianos
Ciclo do Carbono
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.; COMMENT
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180209
[St] Status:MEDLINE
[do] DOI:10.1126/science.aar6329


  7 / 1437 MEDLINE  
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[PMID]:29321473
[Au] Autor:Zobel M; Davison J; Edwards ME; Brochmann C; Coissac E; Taberlet P; Willerslev E; Moora M
[Ad] Endereço:Department of Botany, Institute of Ecology and Earth Sciences, University of Tartu, 40 Lai Street, 51005, Tartu, Estonia.
[Ti] Título:Ancient environmental DNA reveals shifts in dominant mutualisms during the late Quaternary.
[So] Source:Nat Commun;9(1):139, 2018 01 10.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:DNA-based snapshots of ancient vegetation have shown that the composition of high-latitude plant communities changed considerably during the late Quaternary. However, parallel changes in biotic interactions remain largely uninvestigated. Here we show how mutualisms involving plants and heterotrophic organisms varied during the last 50,000 years. During 50-25 ka BP, a cool period featuring stadial-interstadial fluctuations, arbuscular mycorrhizal and non-N-fixing plants predominated. During 25-15 ka BP, a cold, dry interval, the representation of ectomycorrhizal, non-mycorrhizal and facultatively mycorrhizal plants increased, while that of N-fixing plants decreased further. From 15 ka BP, which marks the transition to and establishment of the Holocene interglaciation, representation of arbuscular mycorrhizal plants decreased further, while that of ectomycorrhizal, non-mycorrhizal, N-fixing and wind-pollinated plants increased. These changes in the mutualist trait structure of vegetation may reflect responses to historical environmental conditions that are without current analogue, or biogeographic processes, such as spatial decoupling of mutualist partners.
[Mh] Termos MeSH primário: Evolução Biológica
DNA Antigo/análise
Micorrizas/genética
Plantas/genética
Simbiose
[Mh] Termos MeSH secundário: Ciclo do Carbono/fisiologia
Dióxido de Carbono/química
Dióxido de Carbono/metabolismo
Clima
Ecossistema
Meio Ambiente
História Antiga
Micorrizas/classificação
Nitrogênio/química
Nitrogênio/metabolismo
Fixação de Nitrogênio/fisiologia
Plantas/classificação
Polinização/fisiologia
Datação Radiométrica
[Pt] Tipo de publicação:HISTORICAL ARTICLE; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Ancient); 142M471B3J (Carbon Dioxide); N762921K75 (Nitrogen)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180222
[Lr] Data última revisão:
180222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02421-3


  8 / 1437 MEDLINE  
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[PMID]:28466110
[Au] Autor:Kabel MA; Jurak E; Mäkelä MR; de Vries RP
[Ad] Endereço:Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG, Wageningen, The Netherlands.
[Ti] Título:Occurrence and function of enzymes for lignocellulose degradation in commercial Agaricus bisporus cultivation.
[So] Source:Appl Microbiol Biotechnol;101(11):4363-4369, 2017 Jun.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:The white button mushroom Agaricus bisporus is economically the most important commercially produced edible fungus. It is grown on carbon- and nitrogen-rich substrates, such as composted cereal straw and animal manure. The commercial mushroom production process is usually performed in buildings or tunnels under highly controlled environmental conditions. In nature, the basidiomycete A. bisporus has a significant impact on the carbon cycle in terrestrial ecosystems as a saprotrophic decayer of leaf litter. In this mini-review, the fate of the compost plant cell wall structures, xylan, cellulose and lignin, is discussed. A comparison is made from the structural changes observed to the occurrence and function of enzymes for lignocellulose degradation present, with a special focus on the extracellular enzymes produced by A. bisporus. In addition, recent advancements in whole genome level molecular studies in various growth stages of A. bisporus in compost are reviewed.
[Mh] Termos MeSH primário: Agaricus/enzimologia
Celulose/metabolismo
Lignina/metabolismo
Xilanos/metabolismo
[Mh] Termos MeSH secundário: Agaricus/genética
Agaricus/crescimento & desenvolvimento
Animais
Carbono/metabolismo
Ciclo do Carbono
Genoma Fúngico
Micélio/crescimento & desenvolvimento
Nitrogênio/metabolismo
Solo
Xilanos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Soil); 0 (Xylans); 11132-73-3 (lignocellulose); 7440-44-0 (Carbon); 9004-34-6 (Cellulose); 9005-53-2 (Lignin); N762921K75 (Nitrogen)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171220
[Lr] Data última revisão:
171220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-017-8294-5


  9 / 1437 MEDLINE  
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[PMID]:28938113
[Au] Autor:Mackinder LCM; Chen C; Leib RD; Patena W; Blum SR; Rodman M; Ramundo S; Adams CM; Jonikas MC
[Ad] Endereço:Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA.
[Ti] Título:A Spatial Interactome Reveals the Protein Organization of the Algal CO -Concentrating Mechanism.
[So] Source:Cell;171(1):133-147.e14, 2017 Sep 21.
[Is] ISSN:1097-4172
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Approximately one-third of global CO fixation is performed by eukaryotic algae. Nearly all algae enhance their carbon assimilation by operating a CO -concentrating mechanism (CCM) built around an organelle called the pyrenoid, whose protein composition is largely unknown. Here, we developed tools in the model alga Chlamydomonas reinhardtii to determine the localizations of 135 candidate CCM proteins and physical interactors of 38 of these proteins. Our data reveal the identity of 89 pyrenoid proteins, including Rubisco-interacting proteins, photosystem I assembly factor candidates, and inorganic carbon flux components. We identify three previously undescribed protein layers of the pyrenoid: a plate-like layer, a mesh layer, and a punctate layer. We find that the carbonic anhydrase CAH6 is in the flagella, not in the stroma that surrounds the pyrenoid as in current models. These results provide an overview of proteins operating in the eukaryotic algal CCM, a key process that drives global carbon fixation.
[Mh] Termos MeSH primário: Proteínas de Algas/metabolismo
Ciclo do Carbono
Chlamydomonas reinhardtii/citologia
Chlamydomonas reinhardtii/metabolismo
Cloroplastos/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Algas/química
Dióxido de Carbono/metabolismo
Anidrases Carbônicas/metabolismo
Chlamydomonas reinhardtii/química
Cloroplastos/química
Proteínas Luminescentes/análise
Microscopia Confocal
Fotossíntese
Proteínas de Plantas/metabolismo
Ribulose-Bifosfato Carboxilase/química
Ribulose-Bifosfato Carboxilase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Algal Proteins); 0 (Luminescent Proteins); 0 (Plant Proteins); 142M471B3J (Carbon Dioxide); EC 4.1.1.39 (Ribulose-Bisphosphate Carboxylase); EC 4.2.1.1 (Cah6 protein, Chlamydomonas reinhardtii); EC 4.2.1.1 (Carbonic Anhydrases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171026
[Lr] Data última revisão:
171026
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170923
[St] Status:MEDLINE


  10 / 1437 MEDLINE  
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[PMID]:28934287
[Au] Autor:Zhang X; Han X; Yu W; Wang P; Cheng W
[Ad] Endereço:Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, China.
[Ti] Título:Priming effects on labile and stable soil organic carbon decomposition: Pulse dynamics over two years.
[So] Source:PLoS One;12(9):e0184978, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Soil organic carbon (SOC) is a major component in the global carbon cycle. Yet how input of plant litter may influence the loss of SOC through a phenomenon called priming effect remains highly uncertain. Most published results about the priming effect came from short-term investigations for a few weeks or at the most for a few months in duration. The priming effect has not been studied at the annual time scale. In this study for 815 days, we investigated the priming effect of added maize leaves on SOC decomposition of two soil types and two treatments (bare fallow for 23 years, and adjacent old-field, represent stable and relatively labile SOC, respectively) of SOC stabilities within each soil type, using a natural 13C-isotope method. Results showed that the variation of the priming effect through time had three distinctive phases for all soils: (1) a strong negative priming phase during the first period (≈0-90 days); (2) a pulse of positive priming phase in the middle (≈70-160 and 140-350 days for soils from Hailun and Shenyang stations, respectively); and (3) a relatively stabilized phase of priming during the last stage of the incubation (>160 days and >350 days for soils from Hailun and Shenyang stations, respectively). Because of major differences in soil properties, the two soil types produced different cumulative priming effects at the end of the experiment, a positive priming effect of 3-7% for the Mollisol and a negative priming effect of 4-8% for the Alfisol. Although soil types and measurement times modulated most of the variability of the priming effect, relative SOC stabilities also influenced the priming effect for a particular soil type and at a particular dynamic phase. The stable SOC from the bare fallow treatment tended to produce a narrower variability during the first phase of negative priming and also during the second phase of positive priming. Averaged over the entire experiment, the stable SOC (i.e., the bare fallow) was at least as responsive to priming as the relatively labile SOC (i.e., the old-field) if not more responsive. The annual time scale of our experiment allowed us to demonstrate the three distinctive phases of the priming effect. Our results highlight the importance of studying the priming effect by investigating the temporal dynamics over longer time scales.
[Mh] Termos MeSH primário: Carbono/metabolismo
Folhas de Planta/metabolismo
Solo/química
Zea mays/metabolismo
[Mh] Termos MeSH secundário: Carbono/análise
Ciclo do Carbono
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Soil); 7440-44-0 (Carbon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184978



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