Base de dados : MEDLINE
Pesquisa : G16.500.275.157.437 [Categoria DeCS]
Referências encontradas : 3888 [refinar]
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  1 / 3888 MEDLINE  
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[PMID]:29351323
[Au] Autor:van Nes EH; Staal A; Hantson S; Holmgren M; Pueyo S; Bernardi RE; Flores BM; Xu C; Scheffer M
[Ad] Endereço:Aquatic Ecology and Water Quality Management Group, Environmental Science Department, Wageningen University, Wageningen, The Netherlands.
[Ti] Título:Fire forbids fifty-fifty forest.
[So] Source:PLoS One;13(1):e0191027, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recent studies have interpreted patterns of remotely sensed tree cover as evidence that forest with intermediate tree cover might be unstable in the tropics, as it will tip into either a closed forest or a more open savanna state. Here we show that across all continents the frequency of wildfires rises sharply as tree cover falls below ~40%. Using a simple empirical model, we hypothesize that the steepness of this pattern causes intermediate tree cover (30‒60%) to be unstable for a broad range of assumptions on tree growth and fire-driven mortality. We show that across all continents, observed frequency distributions of tropical tree cover are consistent with this hypothesis. We argue that percolation of fire through an open landscape may explain the remarkably universal rise of fire frequency around a critical tree cover, but we show that simple percolation models cannot predict the actual threshold quantitatively. The fire-driven instability of intermediate states implies that tree cover will not change smoothly with climate or other stressors and shifts between closed forest and a state of low tree cover will likely tend to be relatively sharp and difficult to reverse.
[Mh] Termos MeSH primário: Fogo
Florestas
[Mh] Termos MeSH secundário: Modelos Teóricos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180120
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191027


  2 / 3888 MEDLINE  
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[PMID]:28886495
[Au] Autor:Chen XM; Zhao Y; Ma YY; Zhu LJ; Yang TX; Wei ZM; Dong YL; Wei QB
[Ad] Endereço:College of Life Science, Northeast Agricultural University, Harbin 150030, China.
[Ti] Título:Assessing the environmental impact of phenanthrene in different types of land use based on the binding characteristics with dissolved organic matter.
[So] Source:Ecotoxicol Environ Saf;147:394-400, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The binding characteristics of phenanthrene with dissolved organic matter (DOM) were studied by the excitation emission matrix fluorescence spectroscopy with parallel factor analysis in four types of land use which derived from forest (F), meadow (M), cropland (C), and greenhouse (G). The results showed that the humification degree and binding characteristics of phenanthrene with DOM were distinct differences in the four soils. The binding capacities of humic-like components with phenanthrene were stronger than those of protein-like components. The log K derived from the Stern-Volmer equation significantly correlated with the humification degree of DOM (p < 0.05) in different types of land use. Besides, correlation analysis demonstrated that the potential binding index (Fk) obtained from the modified Stern-Volmer model was a more accurate parameter to describe the combination degree of DOM with phenanthrene than log K, which presented a decrease order of C > F > M > G. Therefore, the environmental impact of phenanthrene in different types of land use could be assessed deeply based on the Fk and DOM concentration.
[Mh] Termos MeSH primário: Monitoramento Ambiental/métodos
Substâncias Húmicas/análise
Fenantrenos/análise
Poluentes do Solo/análise
Solo/química
[Mh] Termos MeSH secundário: Agricultura
China
Análise Fatorial
Florestas
Pradaria
Modelos Teóricos
Solubilidade
Espectrometria de Fluorescência/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Humic Substances); 0 (Phenanthrenes); 0 (Soil); 0 (Soil Pollutants); 448J8E5BST (phenanthrene)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170909
[St] Status:MEDLINE


  3 / 3888 MEDLINE  
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[PMID]:29458505
[Au] Autor:Yan ZF; Lin P; Li CT; Kook M; Yi TH
[Ad] Endereço:1​Department of Oriental Medicinal Material and Processing, College of Life Science, Kyung Hee University Global Campus, 1732 Deokyoungdae-ro, Giheung-gu, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
[Ti] Título:Actinotalea solisilvae sp. nov., isolated from forest soil and emended description of the genus Actinotalea.
[So] Source:Int J Syst Evol Microbiol;68(3):788-794, 2018 Mar.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A Gram-stain-positive, aerobic, non-motile and short-rod-shaped actinobacterium, designated THG-T121 , was isolated from forest soil. Growth occurred at 10-40 °C (optimum 28-30 °C), at pH 6-8 (optimum 7) and at 0-4 % NaCl (optimum 1 %). Based on 16S rRNA gene sequence analysis, the nearest phylogenetic neighbours of strain THG-T121 were identified as Actinotalea ferrariae KCTC 29134 (97.9 %), Actinotalea fermentans KCTC 3251 (97.3 %), Cellulomonas carbonis KCTC 19824 (97.2 %). 16S rRNA gene sequence similarities among strain THG-T121 and other recognized species were lower than 97.0 %. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, two phosphatidylinositol mannosides, one unidentified phospholipid, three unidentified glycolipids and one unidentified lipid. The isoprenoid quinone was menaquinone (MK-10(H4)). The major fatty acids were anteiso-C15 : 0, anteiso-C15 : 1 A, C16 : 0, iso-C16 : 0, anteiso-C17 : 0 and iso-C17 : 0. The whole-cell sugars of strain THG-T121 were rhamnose, ribose, mannose and glucose. The peptidoglycan type of strain THG-T121 is A4ß, containing l-Orn-D-Ser-L-Asp. The DNA G+C content of strain THG-T121 was 72.4 mol%. DNA-DNA hybridization values between strain THG-T121 and A. ferrariae KCTC 29134 , A. fermentans KCTC 3251 and C. carbonis KCTC 19824 were 30.2 % (27.3 %, reciprocal analysis), 28.4 %, (17.3 %) and 16.9 %, (9.3 %), respectively. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain THG-T121 represents a novel species of the genus Actinotalea, for which the name Actinotaleasolisilvae sp. nov. is proposed. The type strain is THG-T121 (=KACC 19191 =CGMCC 4.7389 ).
[Mh] Termos MeSH primário: Actinomycetales/classificação
Florestas
Filogenia
Microbiologia do Solo
[Mh] Termos MeSH secundário: Actinomycetales/genética
Actinomycetales/isolamento & purificação
Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
Ácidos Graxos/química
Glicolipídeos/química
Hibridização de Ácido Nucleico
Peptidoglicano/química
Fosfolipídeos/química
RNA Ribossômico 16S/genética
República da Coreia
Análise de Sequência de DNA
Vitamina K 2/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Glycolipids); 0 (Peptidoglycan); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S); 11032-49-8 (Vitamin K 2)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002584


  4 / 3888 MEDLINE  
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[PMID]:29458457
[Au] Autor:Dahal RH; Kim J
[Ad] Endereço:Department of Life Science, College of Natural Sciences, Kyonggi University, Suwon, Gyeonggi-Do 16227, Republic of Korea.
[Ti] Título:Brevundimonas humi sp. nov., an alphaproteobacterium isolated from forest soil.
[So] Source:Int J Syst Evol Microbiol;68(3):709-714, 2018 Mar.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:During a study of bacterial diversity of soil, a novel strain, CA-15 , was isolated from Kyonggi University forest soil. Cells were aerobic, Gram-stain-negative, motile, non-spore-forming, rod-shaped, oxidase-positive and catalase- negative. Tyrosine was not oxidized but produced red pigmentation on an agar palte. Strain CA-15 hydrolysed Tween 60 and DNA. It grew at 15-35 °C (optimum, 25-30 °C), pH 6.0-10.0 (optimum, 7.0-9.0) and at 1.5 % (w/v) NaCl concentration. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain CA-15 formed a lineage within the family Caulobacteraceae of the class Alphaproteobacteria that was distinct from various species of the genus Brevundimonas. Brevundimonas bullata DSM 7126 was the closest member of strain CA-15 on the basis of 16S rRNA gene sequence similarity (98.48 %). Q-10 was only an isoprenoid quinone detected for strain CA-15 . The major polar lipids were 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1→4)-αd-glucopyranuronosyl]glycerol, 1,2-di-O-acyl-3-O-[αd-glucopyranosyl]-sn-glycerol, 1,2-di-O-acyl-3-O-αd-glucopyranuronosylglycerol, 1,2-diacyl-3-O-[6'-phosphatidyl-αd-glucopyranosyl]glycerol and phosphatidylglycerol. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and C17 : 1ω8c. The DNA G+C content of strain CA-15 was 63.6 mol%. The polyphasic characterization indicated that strain CA-15 represents a novel species in the genus Brevundimonas, for which the name Brevundimonas humi sp. nov. is proposed. The type strain of Brevundimonas humi is CA-15 (=KEMB 9005-528 =KACC 19106 =NBRC 112677 ).
[Mh] Termos MeSH primário: Caulobacteraceae/classificação
Florestas
Filogenia
Microbiologia do Solo
[Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana
Composição de Bases
Caulobacteraceae/genética
Caulobacteraceae/isolamento & purificação
DNA Bacteriano/genética
Ácidos Graxos/química
Hibridização de Ácido Nucleico
Fosfolipídeos/química
Pigmentação
RNA Ribossômico 16S/genética
República da Coreia
Análise de Sequência de DNA
Ubiquinona/análogos & derivados
Ubiquinona/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S); 1339-63-5 (Ubiquinone); EJ27X76M46 (coenzyme Q10)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002559


  5 / 3888 MEDLINE  
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[PMID]:28867554
[Au] Autor:Zhu LJ; Zhao Y; Chen YN; Cui HY; Wei YQ; Liu HL; Chen XM; Wei ZM
[Ad] Endereço:College of Life Science, Northeast Agricultural University, Harbin 150030, China.
[Ti] Título:Characterization of atrazine binding to dissolved organic matter of soil under different types of land use.
[So] Source:Ecotoxicol Environ Saf;147:1065-1072, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Atrazine is widely used in agriculture. In this study, dissolved organic matter (DOM) from soils under four types of land use (forest (F), meadow (M), cropland (C) and wetland (W)) was used to investigate the binding characteristics of atrazine. Fluorescence excitation-emission matrix-parallel factor (EEM-PARAFAC) analysis, two-dimensional correlation spectroscopy (2D-COS) and Stern-Volmer model were combined to explore the complexation between DOM and atrazine. The EEM-PARAFAC indicated that DOM from different sources had different structures, and humic-like components had more obvious quenching effects than protein-like components. The Stern-Volmer model combined with correlation analysis showed that log K values of PARAFAC components had a significant correlation with the humification of DOM, especially for C3 component, and they were all in the same order as follows: meadow soil (5.68)>wetland soil (5.44)>cropland soil (5.35)>forest soil (5.04). The 2D-COS further confirmed that humic-like components firstly combined with atrazine followed by protein-like components. These findings suggest that DOM components can significantly influence the bioavailability, mobility and migration of atrazine in different land uses.
[Mh] Termos MeSH primário: Atrazina/análise
Substâncias Húmicas/análise
Modelos Químicos
Poluentes do Solo/análise
Solo/química
[Mh] Termos MeSH secundário: Agricultura
Atrazina/química
Florestas
Poluentes do Solo/química
Espectrometria de Fluorescência/métodos
Zonas Úmidas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Humic Substances); 0 (Soil); 0 (Soil Pollutants); QJA9M5H4IM (Atrazine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170905
[St] Status:MEDLINE


  6 / 3888 MEDLINE  
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[PMID]:29181902
[Au] Autor:Zheng YM; Hou ZE
[Ad] Endereço:Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
[Ti] Título: sp. nov. (Crustacea, Amphipoda, Talitridae), a new species of landhopper from the high altitude forests in Myanmar.
[So] Source:Zool Res;38(5):281-290, 2017 Sep 18.
[Is] ISSN:2095-8137
[Cp] País de publicação:China
[La] Idioma:eng
[Ab] Resumo:. is described from high altitude habitats in Myanmar. The new species differs morphologically from its congeners by palp of maxilliped narrow; sexually dimorphic gnathopod â…¡, propodus of male chelate and propodus of female mitten-shaped; and dimorphic uropod â…¡, outer ramus of male with small teeth distally, outer ramus of female with three distal spines. Analysis of DNA barcode sequences and niche distinctiveness support recognition of the new species.
[Mh] Termos MeSH primário: Altitude
Anfípodes/anatomia & histologia
Anfípodes/classificação
Florestas
[Mh] Termos MeSH secundário: Anfípodes/fisiologia
Distribuição Animal
Animais
Feminino
Masculino
Mianmar
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[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:171129
[St] Status:MEDLINE
[do] DOI:10.24272/j.issn.2095-8137.2017.067


  7 / 3888 MEDLINE  
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[PMID]:29439235
[Au] Autor:Konarzewski M; Zabielski R; Kowalczyk R; Duszynski J
[Ad] Endereço:Institute of Biology, University of Bialystok, 15-245 Bialystok, Poland.
[Ti] Título:Bialowieza Forest: Logging data lacking.
[So] Source:Science;359(6376):646, 2018 02 09.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Agricultura Florestal
Florestas
[Mh] Termos MeSH secundário: Seres Humanos
Árvores
[Pt] Tipo de publicação:LETTER; COMMENT
[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:180214
[St] Status:MEDLINE
[do] DOI:10.1126/science.aat0295


  8 / 3888 MEDLINE  
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[PMID]:29439234
[Au] Autor:Blicharska M; Smithers RJ
[Ad] Endereço:Natural Resources and Sustainable Development, Department of Earth Sciences, Uppsala University, 75 236 Uppsala, Sweden. malgorzata.blicharska@geo.uu.se.
[Ti] Título:Bialowieza Forest: Political stands.
[So] Source:Science;359(6376):646, 2018 02 09.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Florestas
Árvores
[Pt] Tipo de publicação:LETTER; COMMENT
[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:180214
[St] Status:MEDLINE
[do] DOI:10.1126/science.aar7173


  9 / 3888 MEDLINE  
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[PMID]:29329336
[Au] Autor:Capdevila P; Linares C; Aspillaga E; Riera JL; Hereu B
[Ad] Endereço:Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
[Ti] Título:Effective dispersal and density-dependence in mesophotic macroalgal forests: Insights from the Mediterranean species Cystoseira zosteroides.
[So] Source:PLoS One;13(1):e0191346, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dispersal and recruitment are fundamental processes for population recovery following disturbances in sessile species. While both processes are well understood for many terrestrial species, they still remain poorly resolved for some macroalgal species. Here we experimentally investigated the effective dispersal and recruit survival of a mesophotic Mediterranean fucoid, Cystoseira zosteroides. In three isolated populations, four sets of settlement collectors were placed at increasing distances (from 0 to 10 m) and different orientations (North, South, East and West). We observed that effective dispersal was restricted to populations' vicinity, with an average of 6.43 m and not further than 13.33 m, following a Weibull distribution. During their first year of life, survival was up to 50%, but it was lower underneath the adult canopy, suggesting a negative density-dependence. To put our results in a broader context we compared the effective dispersal of other fucoid and kelp species reported in the literature, which confirmed the low dispersal ability of brown algae, in particular for fucoids, with an effective dispersal of few meters. Given the importance of recruitment for the persistence and recovery of populations after disturbances, these results underline the vulnerability of C. zosteroides and other fucoid species to escalating threats.
[Mh] Termos MeSH primário: Florestas
Feófitas/fisiologia
Dispersão Vegetal
[Mh] Termos MeSH secundário: Conservação dos Recursos Naturais
Ecossistema
Feófitas/crescimento & desenvolvimento
Análise de Sobrevida
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180113
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191346


  10 / 3888 MEDLINE  
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[PMID]:29324901
[Au] Autor:Li S; Lang X; Liu W; Ou G; Xu H; Su J
[Ad] Endereço:Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming, China.
[Ti] Título:The relationship between species richness and aboveground biomass in a primary Pinus kesiya forest of Yunnan, southwestern China.
[So] Source:PLoS One;13(1):e0191140, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The relationship between biodiversity and biomass is an essential element of the natural ecosystem functioning. Our research aims at assessing the effects of species richness on the aboveground biomass and the ecological driver of this relationship in a primary Pinus kesiya forest. We sampled 112 plots of the primary P. kesiya forests in Yunnan Province. The general linear model and the structural equation model were used to estimate relative effects of multivariate factors among aboveground biomass, species richness and the other explanatory variables, including climate moisture index, soil nutrient regime and stand age. We found a positive linear regression relationship between the species richness and aboveground biomass using ordinary least squares regressions. The species richness and soil nutrient regime had no direct significant effect on aboveground biomass. However, the climate moisture index and stand age had direct effects on aboveground biomass. The climate moisture index could be a better link to mediate the relationship between species richness and aboveground biomass. The species richness affected aboveground biomass which was mediated by the climate moisture index. Stand age had direct and indirect effects on aboveground biomass through the climate moisture index. Our results revealed that climate moisture index had a positive feedback in the relationship between species richness and aboveground biomass, which played an important role in a link between biodiversity maintenance and ecosystem functioning. Meanwhile, climate moisture index not only affected positively on aboveground biomass, but also indirectly through species richness. The information would be helpful in understanding the biodiversity-aboveground biomass relationship of a primary P. kesiya forest and for forest management.
[Mh] Termos MeSH primário: Biomassa
Florestas
Pinus
[Mh] Termos MeSH secundário: China
Clima
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191140



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