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1.
Mol Phylogenet Evol ; 186: 107845, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37301485

RESUMO

Intercontinental disjunct distributions can arise either from vicariance, from long-distance dispersal, or through extinction of an ancestral population with a broader distribution. Tectariaceae s.l., a clade of ferns in Polypodiales with ca. 300 species mainly distributed in the tropics and subtropics, provide an excellent opportunity to investigate global distribution patterns. Here, we assembled a dataset of eight plastid markers and one nuclear marker of 636 (92% increase of the earlier largest sampling) accessions representing ca. 210 species of all eight genera in Tectariaceae s.l. (Arthropteridaceae, Pteridryaceae, and Tectariaceae s.s.) and 35 species of other families of eupolypods Ⅰ. A new phylogeny is reconstructed to study the biogeography and trait-associated diversification. Our major results include: (1) a distinct lineage of Tectaria sister to the rest of the American Tectaria is identified; (2) Tectariaceae s.l., and the three families: Arthropteridaceae (Arthropteris), Pteridryaceae (Draconopteris, Malaifilix, Polydictyum, Pteridrys), and Tectariaceae s.s. (Hypoderris, Tectaria, and Triplophyllum), might have all originated in late Cretaceous; (3) only five intercontinental dispersals occurred in Pteridryaceae and Tectariaceae s.s. giving rise to their current intercontinental disjunction; (4) we provide the second evidence in ferns that a long-distance dispersal between Malesia and Americas during the Paleocene to Eocene led to the establishment/origin of a new genus (Draconopteris); and (5) diversification rate of each state of leaf dissection is different, and the lowest is in the simple-leaved taxa.


Assuntos
Gleiquênias , Filogenia , Plastídeos , Filogeografia , Teorema de Bayes
2.
Sci Total Environ ; 808: 151990, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34843779

RESUMO

A novel food such as plant cell culture (PCC) is an important complementary asset for traditional agriculture to tackle global food insecurity. To evaluate environmental impacts of PCC, a life cycle assessment was applied to tobacco bright yellow-2 and cloudberry PCCs. Global warming potential (GWP), freshwater eutrophication potential (FEUP), marine eutrophication potential, terrestrial acidification potential (TAP), stratospheric ozone depletion, water consumption and land use were assessed. The results showed particularly high contributions (82-93%) of electricity consumption to GWP, FEUP and TAP. Sensitivity analysis indicated that using wind energy instead of the average Finnish electricity mix reduced the environmental impacts by 34-81%. Enhancement in the energy efficiency of bioreactor mixing processes and reduction in cultivation time also effectively improved the environmental performance (4-47% reduction of impacts). In comparison with other novel foods, the environmental impacts of the PCC products studied were mostly comparable to those of microalgae products but higher than those of microbial protein products produced by autotrophic hydrogen-oxidizing bacteria. Assayed fresh PCC products were similar or close to GWP of conventionally grown food products and, with technological advancements, can be highly competitive.


Assuntos
Agricultura , Meio Ambiente , Animais , Técnicas de Cultura de Células , Eutrofização , Aquecimento Global , Estágios do Ciclo de Vida
3.
Sci Total Environ ; 776: 145764, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33639472

RESUMO

Novel food production technologies are being developed to address the challenges of securing sustainable and healthy nutrition for the growing global population. This study assessed the environmental impacts of microbial protein (MP) produced by autotrophic hydrogen-oxidizing bacteria (HOB). Data was collected from a company currently producing MP using HOB (hereafter simply referred to as MP) on a small-scale. Earlier studies have performed an environmental assessment of MP on a theoretical basis but no study yet has used empirical data. An attributional life cycle assessment (LCA) with a cradle-to-gate approach was used to quantify global warming potential (GWP), land use, freshwater and marine eutrophication potential, water scarcity, human (non-)carcinogenic toxicity, and the cumulative energy demand (CED) of MP production in Finland. A Monte Carlo analysis was performed to assess uncertainties while a sensitivity analysis was used to explore the impacts of alternative production options and locations. The results were compared with animal- and plant-based protein sources for human consumption as well as protein sources for feed. Electricity consumption had the highest contribution to environmental impacts. Therefore, the source of energy had a substantial impact on the results. MP production using hydropower as an energy source yielded 87.5% lower GWP compared to using the average Finnish electricity mix. In comparison with animal-based protein sources for food production, MP had 53-100% lower environmental impacts depending on the reference product and the source of energy assumed for MP production. When compared with plant-based protein sources for food production, MP had lower land and water use requirements, and eutrophication potential but GWP was reduced only if low-emission energy sources were used. Compared to protein sources for feed production, MP production often resulted in lower environmental impact for GWP (FHE), land use, and eutrophication and acidification potential, but generally caused high water scarcity and required more energy.


Assuntos
Bactérias , Hidrogênio , Animais , Finlândia , Humanos , Estágios do Ciclo de Vida , Oxirredução
4.
Ecol Evol ; 11(24): 17672-17685, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35003631

RESUMO

We investigated how the phylogenetic structure of Amazonian plant communities varies along an edaphic gradient within the non-inundated forests. Forty localities were sampled on three terrain types representing two kinds of soil: clayey soils of a high base cation concentration derived from the Solimões formation, and loamy soils with lower base cation concentration derived from the Içá formation and alluvial terraces. Phylogenetic community metrics were calculated for each locality for ferns and palms both with ferns as one group and for each of three fern clades with a crown group age comparable to that of palms. Palm and fern communities showed significant and contrasting phylogenetic signals along the soil gradient. Fern species richness increased but standard effect size of mean pairwise distance (SES.MPD) and variation of pairwise distances (VPD) decreased with increasing soil base cation concentration. In contrast, palm communities were more species rich on less cation-rich soils and their SES.MPD increased with soil base cation concentration. Species turnover between the communities reflected the soil gradient slightly better when based on species occurrences than when phylogenetic distances between the species were considered. Each of the three fern subclades behaved differently from each other and from the entire fern clade. The fern clade whose phylogenetic patterns were most similar to those of palms also resembled palms in being most species-rich on cation-poor soils. The phylogenetic structuring of local plant communities varies along a soil base cation concentration gradient within non-inundated Amazonian rain forests. Lineages can show either similar or different phylogenetic community structure patterns and evolutionary trajectories, and we suggest this to be linked to their environmental adaptations. Consequently, geological heterogeneity can be expected to translate into a potentially highly diverse set of evolutionarily distinct community assembly pathways in Amazonia and elsewhere.

6.
Sci Rep ; 6: 18140, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26728164

RESUMO

Agriculture is one of the largest anthropogenic sources of greenhouse gases (GHGs), with dairy and beef production accounting for nearly two-thirds of emissions. Several recent papers suggest that dung beetles may affect fluxes of GHGs from cattle farming. Here, we put these previous findings into context. Using Finland as an example, we assessed GHG emissions at three scales: the dung pat, pasture ecosystem, and whole lifecycle of milk or beef production. At the first two levels, dung beetles reduced GHG emissions by up to 7% and 12% respectively, mainly through large reductions in methane (CH4) emissions. However, at the lifecycle level, dung beetles accounted for only a 0.05-0.13% reduction of overall GHG emissions. This mismatch derives from the fact that in intensive production systems, only a limited fraction of all cow pats end up on pastures, offering limited scope for dung beetle mitigation of GHG fluxes. In contrast, we suggest that the effects of dung beetles may be accentuated in tropical countries, where more manure is left on pastures, and dung beetles remove and aerate dung faster, and that this is thus a key area for future research. These considerations give a new perspective on previous results, [corrected] and suggest that studies of biotic effects on GHG emissions from dung pats on a global scale are a priority for current research.


Assuntos
Agricultura , Besouros , Gases , Efeito Estufa , Criação de Animais Domésticos , Animais , Bovinos , Monitoramento Ambiental , Finlândia
7.
Acta amaz ; 45(4): 393-404, out.-dez. 2015. map, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455270

RESUMO

Forest structure determines light availability for understorey plants. The structure of lowland Amazonian forests is known to vary over long edaphic gradients, but whether more subtle edaphic variation also affects forest structure has not beenresolved. In western Amazonia, the majority of non-flooded forests grow on soils derived either from relatively fertile sediments of the Pebas Formation or from poorer sediments of the Nauta Formation. The objective of this study was to compare structure and light availability in the understorey of forests growing on these two geological formations. We measured canopy openness and tree stem densities in three size classes in northeastern Peru in a total of 275 study points in old-growth terra firme forests representing the two geological formations. We also documented variation in floristic composition (ferns, lycophytes and the palm Iriartea deltoidea) and used Landsat TM satellite image information to model the forest structural and floristic features over a larger area. The floristic compositions of forests on the two formations were clearly different, and this could also be modelled with the satellite imagery. In contrast, the field observations of forest structure gave only a weak indication that forests on the Nauta Formation might be denser than those on the Pebas Formation. The modelling of forest structural features with satellite imagery did not support this result. Our results indicate that the structure of forest understorey varies much less than floristic composition does over the studied edaphic difference.


A estrutura florestal determina a disponibilidade de luz para plantas do subosque. Nas planícies Amazônicas, a estrutura florestal varia com fortes gradientes edáficos. O possível efeito de variações edáficas mais sutis sob a estrutura das florestas não está resolvido. Na Amazônia ocidental, a maioria das florestas não-inundadas crescem em solos derivados de sedimentos relativamente férteis da Formação Pebas ou de sedimentos mais pobres da Formação Nauta. Nosso objetivo é comparar a disponilidade de luz e a estrutura do subosque de florestas crescendo sobre duas formações geológicas. Nós medimos a abertura do dossel e a densidade de troncos de árvores em três classes de diâmetro no nordeste Peruano, totalizando 275 pontos de estudo em florestas de terra-firme representando as duas formações geológicas. Além disso, documentamos as variações na composição florística (samambaias, licófitas e a palmeira Iriartea deltoidea) e utilizamos informações de imagens de satélite Landsat TM para modelar as características estruturais e florísticas das florestas em uma área mais ampla. A composição florística sobre as duas formações foram claramente distintas e isso também pôde ser modelado com as imagens de satélite. Já as observações de campo sobre a estrutura da floresta deram uma fraca indicação de que as florestas sobre a Formação Nauta poderiam ser mais densas do que as florestas sobre a Formação Pebas. A modelagem das caraterísticas da estrutura florestal com imagens de satélite não deram o mesmo resultado. Nossos resultados indicam que a estrutura do subosque varia muito menos do que composição florística no gradiente edáfico estudado.


Assuntos
Florestas , Luz Solar , Traqueófitas
8.
Environ Sci Technol ; 49(8): 5211-9, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25790272

RESUMO

This meta-analysis quantifies the changes in greenhouse gas (GHG) emissions from dairy farms, caused by anaerobically digesting (AD) cattle manure. As this is a novel quantifiable synthesis of the literature, a database of GHG emissions from dairy farms is created. Each case in the database consists of a baseline (reference with no AD system) and an AD scenario. To enable interstudy comparison, emissions are normalized by calculating relative changes (RCs). The distributions of RCs are reported by specific GHGs and operation units. Nonparametric tests are applied to the RCs in order to identify a statistical difference of AD with respect to baseline scenarios (Wilcoxon rank test), correlations (Spearman test), and best estimation for changes in emissions (Kernel density distribution estimator). From 749 studies identified, 30 papers yield 89 independent cases. The median reductions in emissions from the baseline scenarios, according to operation units, are -43.2% (n.s.) for storage, -6.3% for field application of slurries, -11.0% for offset of energy from fossil fuel, and +0.4% (n.s.) for offset of inorganic fertilizers. The leaks from digesters are found to significantly increase the emissions from baseline scenarios (median = +1.4%).


Assuntos
Indústria de Laticínios , Eliminação de Resíduos Líquidos/métodos , Poluentes Atmosféricos/análise , Anaerobiose , Animais , Bovinos , Indústria de Laticínios/métodos , Esterco
9.
Maturitas ; 71(2): 173-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22197594

RESUMO

OBJECTIVES: To evaluate whether healthy women show cognitive changes after menopause and whether the possible changes are oestrogen-, age- or education-dependent. METHODS: Forty-eight women, 21 perimenopausal (aged 43-51 years) and 27 late postmenopausal (aged 59-71 years), participated in the study. Verbal and visuomotor functions, visuoconstructive skills, visual and verbal episodic memory as well as attention were evaluated. RESULTS: Perimenopausal women performed better than postmenopausal women. Serum oestradiol (E(2)) level was included in the model in perimenopausal women only given the lack of endogenous oestrogen in postmenopausal women who were also not using hormone therapy (HT). In perimenopausal women, lower E(2) was associated with better visual episodic memory (p<.05), and older age was related to poorer verbal episodic memory (p<.05). In postmenopausal women, more education was associated with better performance in verbal and visuomotor functions, attention as well as verbal episodic memory (p<.05), older age was related to poorer performance in the visuoconstructive test and visual episodic memory (p<.05). CONCLUSIONS: Perimenopausal women had better cognitive performance compared to late postmenopausal women. In perimenopausal women the effect of E(2) was minor. In both groups, age modified cognitive performance, but more so in postmenopausal women. Education did not have any effect on cognitive performance in perimenopausal women, whereas in postmenopausal women education exceeded age as a source of variation. Thus the relevance of education for better cognition was accentuated after menopause.


Assuntos
Atenção , Cognição , Estradiol/sangue , Memória , Perimenopausa/psicologia , Pós-Menopausa/psicologia , Desempenho Psicomotor , Adulto , Fatores Etários , Idoso , Escolaridade , Feminino , Humanos , Pessoa de Meia-Idade , Perimenopausa/sangue , Pós-Menopausa/sangue
10.
J Obstet Gynaecol Res ; 36(4): 796-802, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20666948

RESUMO

AIMS: The use of hormone therapy (HT) is a relevant and topical issue in the treatment of menopausal symptoms in women. Information regarding the effects of combination treatment with estrogen and progesterone as well as treatment timing on cognitive function is lacking and was evaluated in healthy pre- and postmenopausal women. METHODS: Sixteen premenopausal (45-51 years) and 16 postmenopausal (58-70 years) women were randomly assigned to receive either estrogen + progestin therapy (HT) or placebo (PL) for six months. The study was double-blind. Cognitive performance was measured at baseline and follow up with tests of verbal and visuomotor functions, verbal and visual memory, and attention. RESULTS: In premenopausal women, cognitive attention, when compared to baseline, improved with HT but declined slightly with PL in the two-choice reaction time task (P = 0.049), while PL was associated with better performance in tests of shared attention (P = 0.024) and auditory attention (P < 0.05). In postmenopausal women, HT was associated with improved performance in verbal episodic memory (P = 0.024) and a minor decline in auditory attention (P = 0.025). CONCLUSIONS: HT, with estradiol valerate and norethisterone, in healthy women showed only minor effects on attention around the menopausal transition and on memory in postmenopause.


Assuntos
Atenção/efeitos dos fármacos , Cognição/efeitos dos fármacos , Estradiol/análogos & derivados , Memória/efeitos dos fármacos , Noretindrona/administração & dosagem , Idoso , Método Duplo-Cego , Quimioterapia Combinada , Estradiol/administração & dosagem , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/efeitos dos fármacos
11.
Acta amaz ; 24(1)1994.
Artigo em Espanhol | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454527

RESUMO

Floristic composition of twelve plots, 25 m by 25 m, was studied in the Peruvian Amazonia in order to investigate if it were possible to use a part of the flora as an indicator of the changes observed in other components of the flora. Floristic similarities among the plots were calculated using six different taxonomic or physiognomic groups: ferns, the families Melastomataceae and Myristicaceae, trees thicker than 2.5 cm diameter at breast hight (DBH), trees between 2.5 cm and 5 cm DBH, and trees thicker than 5 cm DBH. The similarities were used for agglomerati ve classifications of the plots and for analyzing the correlations among the different groups of plants with Mantel's test. The results indicate that floristic changes were similar in all of the groups and therefore every group can potentially be used as an indicator.


Um estudo da composição florística de doze parcelas de 25 m 25 m foi realizado na Amazônia peruana com o objetivo de observar a possibilidade de utilizar uma parte da flora como indicador para as alterações anotadas em outros elementos da flora. As similaridades florísticas entre as parcelas foram definidas usando seis grupos taxonômicos ou fisionômicos diferentes: fetos, as famílias Melastomataceae e Myristicaceae, árvores com diâmetro á altura do peito (DAP) maior a 2.5 cm, árvores com DAP entre 2.5 cm e 5 cm, e árvores maiores a 5 cm de DAP. As similaridades foram utilizadas para classificar as parcelas e para analisar as correlações entre os grupos diferentes de plantas com a prova de Mantel. Os resultados mostram que as alterações florísticas são similares em todos os grupos, e por isso qualquer destes grupos é capaz de servir de indicador.

12.
Acta amaz ; 22(3)jul.-set. 1992.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454441

RESUMO

It has been suggested that a huge lake, Lago Amazonas, covered a large part of the Amazon basin until as recently as two thousand years ago. According to this hypothesis, the topmost sediments in western Amazonia are almost universally young deposite of lacustrine and deltaic origin. The hypothesis has gained some attention among biologists because of its implications for biological phenomena in Amazonia, especially biogeography and biodiversity. According to the available geological data, however, Amazonia is geologically far more complex than assumed by the lake hypothesis. In the following discussion we will point out the weaknesses of the Lago Amazonas hypothesis, and indicate alternative explanations of the surface geology that are based on tectonically controlled fluvial deposition.


Foi proposta a idéia que uma parte importante da bacia do Amazonas foi coberta por um vasto lago, Lago Amazonas, até há época tão recente como dois mil anos atrás. Segundo esta hipótese os sedimentos de topo na região ocidental da Amazônia são quase universalmente depósitos recentes de origem lacustre e estuário. A hipótese tem chamado atenção dos biólogos pelas suas implicações com fenômenos biológicos na Amazônia, particularmente com a biogeografìa e a biodiversidade.A Amazônia, apresenta, contudo, uma unidade geologicamente muito mais complexa do que pressupõe esta hipótese de lago, hipótese que nem tem apoio dos dados disponíveis sobre o tectonismo, a geomorfologia, a estratigrafia e os solos. Vastas áreas nas regiões do Peru e da Bolivia da bacia do Amazonas se caracterizam atualmente pela deposição fluvial, dominada pelos processos tectônicais. São processos que foram ativos durante dezenas de milhões de anos explicando assim a acumulação dos sedimentos Quaternários não-consolidados, característicos da região ocidental da Amazônia. Há uma variação extensa dos sedimentos de topo tanto pela sua composição como pela sua idade devido às influências locais de fatores diferentes. A hipótese que pressupõe o ambiente de depósitos ter no recente passado diferido basicamente do ambiente atual, precisava, para ser aceita, provas mais convincentes do que foi presentado pelos proponentes da hipótese de Lago Amazonas.Devido à instalidade e heterogeneidade do meio ambiente da Amazônia, é preciso prudência quando se generaliza baseando-se nas observações duma área limitada. Sistemas de depósitos diferentes são capazes de produzir sedimentos estratigrafica mente semelhantes, independentemente um do outro. Sem ter provas evidentes tanto da continuidade como da deposição simultanea, estabelecer uma correlação entre formações de locais remotos parece muito arriscado.

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