1,089 research outputs found

    Accumulated Carbon Fractions in Tropical Sandy Soils and Their Effects on Fertility and Grain Yield in an Integrated Crop‚ÄďLivestock System

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    Food production in sandy soils has evolved significantly, most notably through the advent of integrated crop‚Äďlivestock systems (ICLSs). ICLSs increase soil cover, which maintains soil moisture and sequesters carbon (C). Here we investigate the influence of ICLSs on soil physical, chemical, and biochemical properties, and grain yield (GY) in tropical sandy soils in short-time. We compared seven ICLSs in two consecutive crops seasons (with soybean or maize as cash crops) in southeastern Brazil. These were (1) corn + Urochloa brizantha cv. BRS Paiagu√°s‚ÄĒsoybean (ICL-Paiagu√°s); (2) corn + U. brizantha cv. BRS Piat√£‚ÄĒsoybean; (3) corn + U. ruziziensis‚ÄĒsoybean; (4) corn‚Äďsoybean under conventional tillage (CT) as a negative control; (5) corn‚Äďsoybean under no-tillage (NT) as a positive control; (6) Paiagu√°s grass‚ÄĒcontinuous grazing (Perennial Paiagu√°s); (7) and Piat√£ grass‚ÄĒcontinuous grazing (Perennial Piat√£). Soybean and corn GY data, soil physical and chemical attributes, and soil enzymatic activity were subjected to descriptive statistics and multivariate analysis. CT and NT shared high loadings of H + Al, Al, and soil temperature and low loadings of soil pH, SOM physical and chemical fractions, cationic exchange capacity, and arylsulfatase activity. ICL-Paiagu√°s and Perennial Piat√£ had a similarly high loading of total N, humin, total organic carbon, and mineral-associated carbon stocks. The fulvic acid fraction was the most sensitive to C accumulation in the sandy soil under ICLSs. Soil water and thermal regimes were limiting in both CT and NT. The study not only confirms the capacity of conservation mechanisms to enhance soil-based ecosystem functions, but it also highlights the potential of ICLSs to aid sustainable food production even in the context of tropical sandy soils, which frequently receive limited attention in intensive agricultural practices

    The Importance of Including Spatial Autocorrelation When Modelling Species Richness in Archipelagos: A Bayesian Approach

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    One of the aims of island biogeography theory is to explain the number of species in an archipelago. Traditionally, the variables used to explain the species richness on an island are its area and distance to the mainland. However, increasing evidence suggests that accounting for other variables is essential for better estimates. In particular, the distance between islands should play a role in determining species richness. This work uses a Bayesian framework using Gaussian processes to assess whether distance to neighbouring islands (spatial autocorrelation) can better explain arthropod species richness patterns in the Azores Archipelago and in the Canary Islands. This method is flexible and allows the inclusion of other variables, such as maximum altitude above sea level (elevation). The results show that accounting for spatial autocorrelation provides the best results for both archipelagos, but overall, spatial autocorrelation seems to be more important in the Canary archipelago. Similarly, elevation plays a more important role in determining species richness in the Canary Islands. We recommend that spatial autocorrelation should always be considered when modelling an archipelago’s species richness

    Relationship between sensory and microbial profiles of fermented coffee by dry and washed methods

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    Microorganisms influence the sensory quality of the coffee beverage through the compounds degradation or release of metabolites that diffuse into the fruit. However, type and duration of fermentation can contribute to the growth and diversity of microorganisms. Thus, the objective of this study was to analyze the microbial and sensory profile of Arabica coffees under different fruit-processing conditions and fermentation by Saccharomyces cerevisiae. Coffee cherries were used in the dry fermentation and washed fermentation at 28¬įC. Fermentation time ranged from 36 to 288 hours. A panel of sensory attributes was evaluated by 9 Q-graders. Mid-infrared spectra were obtained in the wavenumber range from 4000 to 650 cm‚ąí1. Microbial analyses were performed by denaturing gradient gel electrophoresis. Total sensory score for fermented coffee was higher than for unfermented coffee. In 108 and 216 hours of fermentation, the total score was higher in washed fermentation than in dry fermentation, which also shows the influence of post-harvest processing and the removal of husk on the quality of fermented coffee. Balance and body were the sensory attributes that most contributed to group formation in dry fermentation. Thus, induced fermentation increases the sensory classification of coffee beverages with positive effects on chemical and sensory profiles

    Livro Vermelho dos Mamíferos de Portugal Continental

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    A publica√ß√£o deste Livro Vermelho, o primeiro inteiramente dedicado aos mam√≠feros, teve a ambi√ß√£o de ir bastante al√©m do seu objetivo central ‚Äď avaliar o risco de extin√ß√£o das esp√©cies de Portugal Continental. Entre os objetivos suplementares deste projeto incluem-se: (i) compilar toda a informa√ß√£o existente sobre a ocorr√™ncia de mam√≠feros no territ√≥rio nacional, como dados museol√≥gicos, resultados de censos e programas de monitoriza√ß√£o, trabalhos cient√≠ficos, dados sobre a atividade cineg√©tica e relat√≥rios; (ii) obter nova informa√ß√£o no terreno para enriquecer a existente, atrav√©s da realiza√ß√£o de invent√°rios focados especialmente na Rede Nacional de √Āreas Protegidas e na Rede Natura 2000. Esta componente cr√≠tica do projeto beneficiou de numerosas t√©cnicas de inventaria√ß√£o de mam√≠feros como, por exemplo, armadilhagem fotogr√°fica, captura com redes e armadilhas, inventaria√ß√£o ac√ļstica e observa√ß√Ķes realizadas por cidad√£os. A identifica√ß√£o de muitos dos animais capturados foi confirmada com t√©cnicas moleculares, que permitiram esclarecer d√ļvidas sobre a identidade de esp√©cies dif√≠ceis de distinguir; (iii) consolidar toda a informa√ß√£o sobre ocorr√™ncia de esp√©cies numa base de dados; (iv) estimar os par√Ęmetros necess√°rios para realizar uma avalia√ß√£o do estatuto das esp√©cies, incluindo a sua extens√£o de ocorr√™ncia, √°rea de ocupa√ß√£o e par√Ęmetros populacionais; (v) contribuir para a avalia√ß√£o do estado de conserva√ß√£o das esp√©cies de mam√≠feros abrangidas pela Diretiva Habitats; (vi) contribuir para a divulga√ß√£o, junto do p√ļblico em geral, da fauna de mam√≠feros e dos seus problemas de conserva√ß√£o em Portugal, atrav√©s de iniciativas nos media, da publica√ß√£o deste livro e da cria√ß√£o de uma p√°gina na internet. Com base em toda a informa√ß√£o recolhida, e gra√ßas √† colabora√ß√£o de uma enorme equipa de especialistas em mam√≠feros, foi poss√≠vel atribuir √† maioria das esp√©cies uma das categorias de amea√ßa com base nos crit√©rios e procedimentos indicados pela UICN, descritos no cap√≠tulo dedicado aos m√©todos

    Relationship between motor competence, weight status, and cardiorespiratory fitness from 7 to 16 years of age

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    Strong evidence has been found for a negative relationship between motor competence (MC) and weight status (WS), and a positive one between MC and health related fitness (HRF).European Regional Development Fundinfo:eu-repo/semantics/publishedVersio

    Brominated flame retardants and natural organobrominated compounds in a vulnerable delphinid species along the Brazilian coast

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    Guiana dolphins, Sotalia guianensis, are vulnerable to extinction along their distribution on the Brazilian coast and assessing chemical pollution is of utmost importance for their conservation. For this study, 51 carcasses of Guiana dolphins were sampled across the Brazilian coast to investigate legacy and emerging brominated flame retardants (BFRs) as well as the naturally-produced MeO-BDEs. PBDEs and MeO-BDEs were detected in all samples analyzed, whereas emerging BFRs were detected in 16 % of the samples, all in Rio de Janeiro state. PBDE concentrations varied between 2.24 and 799 ng.g-1 lipid weight (lw), emerging BFRs between 0.12 and 1.51 ng.g-1 lw and MeO-BDEs between 3.82 and 10,247 ng.g-1 lw. Concentrations of legacy and emerging BFRs and natural compounds varied considerably according to the sampling site and reflected both the local anthropogenic impact of the region and the diversity/mass of biosynthesizers. The PBDE concentrations are lower than what was found for delphinids in the Northern Hemisphere around the same sampling period and most sampling sites presented mean concentrations lower than the limits for endocrine disruption known to date for marine mammals of 460 ng.g-1 lw, except for sampled from Santa Catarina state, in Southern Brazil. Conversely, MeO-BDE concentrations are higher than those of the Northern Hemisphere, particularly close to the Abrolhos Bans and Royal Charlotte formation, that are hotspots for biodiversity. Despite the elevated concentrations reported for this group, there is not much information regarding the effects of such elevated concentrations for these marine mammals. The distinct patterns observed along the Brazilian coast show that organobrominated compounds can be used to identify the ecological segregation of delphinids and that conservation actions should be planned considering the local threats.A.F. Azevedo and J. Lailson-Brito thank the National Council for Scientific and Technological Development (CNPq) for grants PQ-1B and 1D, respectively; and UERJ (Prociência). We thank the students from Aquatic Mammal and Bioindicator Lab (UERJ - Brazil), Environmental Chemistry Lab (CSIC - Spain) and Radioisotope Lab (UFRJ - Brazil). L.G. Vidal thanks the Coordination for the Improvement of Higher Education Personnel (CAPES - Finance Code 001) for providing her PhD grant. The authors thank the ICMBio - Estação Ecológica de Tamoios (ESEC Tamoios) and APA de Guapi-Mirim/ESEC da Guanabara for supporting the collection of carcasses in Ilha Grande Bay.Peer reviewe

    Statistical analysis of blast-induced vibration near an open pit mine

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    Abstract Blast-induced vibration may be harmful to facilities in the vicinity of operating mines, mainly causing structural damage and human discomfort. This study presents an application of multivariate statistics to predict vibration levels regarding their potential to cause structural damage and human discomfort. An extensive seismic monitoring campaign was executed in a large open-pit iron ore mine, near a small village, to gather a dataset for a predictive multivariate analysis. Ten blasting events have produced a dataset of 158 valid measurements. Three classes of vibration peak velocity were adopted from legal standards, which later supported a cluster analysis. Then, it was possible to compare how much these two classification modalities respond to discriminant analysis. The next step was to carry out a principal component analysis (PCA) from the original database, and, comparatively, to plot both the scores concerning the classes derived from the vibration standard and those from the groups obtained from cluster analysis. PCA has considerably explained the data variability, while the three classes from cluster analysis resulted very similar to the corresponding ones from the vibration standards. The results have demonstrated that multivariate statistics may be applied to manage blasting-induced vibration and its deleterious effects with few adjustments and automation
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